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HFES Tables of Contents: 000102030405060708091011121314

Proceedings of the Human Factors and Ergonomics Society 46th Annual Meeting 2002-09-30

Fullname:Proceedings of the Human Factors and Ergonomics Society 46th Annual Meeting
Note:Bridging Fundamentals & New Opportunities
Location:Baltimore, Maryland
Dates:2002-Sep-30 to 2002-Oct-04
Publisher:HFES
Standard No:ISBN: 0-945289-20-0; hcibib: HFES02; TA 166 H794
Papers:464
Pages:2205
Links:Online Proceedings | Online Order Form
  1. HFES 2002-09-30 Volume 46
    1. AEROSPACE SYSTEMS: Information Display and Situation Awareness in the Cockpit [Lecture]
    2. AEROSPACE SYSTEMS: Performance Enhancement in Aerospace Systems [Lecture]
    3. AEROSPACE SYSTEMS: Air Traffic Control and Traffic Flow Management [Lecture]
    4. AEROSPACE SYSTEMS: Decision Making in Aviation [Lecture]
    5. AEROSPACE SYSTEMS: Information Displays and Decision Support in Aviation Systems [Lecture]
    6. AEROSPACE SYSTEMS: Understanding and Enhancing Human Performance in Aviation [Lecture]
    7. AEROSPACE SYSTEMS: Aerospace Systems Posters
    8. AGING: Older Adults and Computer Systems [Lecture]
    9. AGING: Aging and Everyday Applications [Lecture]
    10. AGING: Aging Posters
    11. COGNITIVE ENGINEERING AND DECISION MAKING: Articles
    12. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Processes [Lecture]
    13. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Engineering and Design [Lecture]
    14. COGNITIVE ENGINEERING AND DECISION MAKING: Human and Machine Decision Making [Lecture]
    15. COGNITIVE ENGINEERING AND DECISION MAKING: Automation [Lecture]
    16. COGNITIVE ENGINEERING AND DECISION MAKING: Methods in Cognitive Engineering and Decision Making [Lecture]
    17. COGNITIVE ENGINEERING AND DECISION MAKING: Aviation and Cognitive Engineering [Lecture]
    18. COGNITIVE ENGINEERING AND DECISION MAKING: Decision Aids and Trust [Lecture]
    19. COGNITIVE ENGINEERING AND DECISION MAKING: Articles
    20. COGNITIVE ENGINEERING AND DECISION MAKING: Decision Aids and Trust [Lecture]
    21. COGNITIVE ENGINEERING AND DECISION MAKING: Decision Making in the Armed Forces [Lecture]
    22. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Task Analysis and Cognitive Modeling [Lecture]
    23. COGNITIVE ENGINEERING AND DECISION MAKING: Decision Making [Lecture]
    24. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Work Analysis for Large-Scale Systems: Recurring Issues [Symposium]
    25. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Engineering & Decision Making Posters
    26. COMMUNICATIONS: Cheeseburgers, Cocktail Parties, and Segregated-Multiple-Talker-Scanpath Hors D'Oeuvres [Lecture]
    27. COMMUNICATIONS: Communication Posters
    28. COMPUTER SYSTEMS: Multimodal Input [Lecture]
    29. COMPUTER SYSTEMS: Distinguished Speaker [Invited Address]
    30. COMPUTER SYSTEMS: Methods and More [Lecture]
    31. COMPUTER SYSTEMS: Computer Systems Posters
    32. CONSUMER PRODUCTS: Articles
    33. CONSUMER PRODUCTS: Physical Considerations for Consumer Product Design [Lecture]
    34. CONSUMER PRODUCTS: Psychological Considerations for Consumer Product Design [Lecture]
    35. CONSUMER PRODUCTS: Consumer Products Posters
    36. DEMONSTRATIONS: Tools for Team Performance Capture, Team Knowledge Assessment, Motion in Virtual Displays, and Immersive Displays on the Cheap! [Demonstrations]
    37. EDUCATION: Teaching HF and Web-Based Instruction [Lecture]
    38. EDUCATION: Education Posters
    39. ENVIRONMENTAL DESIGN: Environmental Design Potpourri [Lecture]
    40. FORENSICS PROFESSIONAL: Issues in Forensic Human Factors
    41. FORENSICS PROFESSIONAL: Forensics Professional Posters
    42. GENERAL SESSION: Thinking About, and In, the World
    43. GENERAL SESSION: General Sessions Posters
    44. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences and Cognition [Lecture]
    45. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences Potpourri [Lecture]
    46. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Performance Posters
    47. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences Potpourri [Lecture]
    48. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Performance Posters
    49. INDUSTRIAL ERGONOMICS: Ergonomic Risk Exposure Assessment [Lecture]
    50. INDUSTRIAL ERGONOMICS: Upper Extremity Research I [Lecture]
    51. INDUSTRIAL ERGONOMICS: Trunk/Torso I [Lecture]
    52. INDUSTRIAL ERGONOMICS: Fatigue Research [Lecture]
    53. INDUSTRIAL ERGONOMICS: Physical and Mental Workplace Factors [Lecture]
    54. INDUSTRIAL ERGONOMICS: Upper Extremity Research II [Lecture]
    55. INDUSTRIAL ERGONOMICS: Trunk/Torso II [Lecture]
    56. INDUSTRIAL ERGONOMICS: Ergonomic Movement Research [Lecture]
    57. INDUSTRIAL ERGONOMICS: Intervention Ergonomics [Lecture]
    58. INDUSTRIAL ERGONOMICS: Industrial Ergonomics Posters
    59. INTERNET: Usability Methods, Design, and User Perceptions [Lecture]
    60. INTERNET: Search Performance and Usability Issues [Lecture]
    61. INTERNET: Internet Posters
    62. MACROERGONOMICS: Macroergonomics [Lecture]
    63. MACROERGONOMICS: Macroergonomics Poster
    64. MEDICAL SYSTEMS AND REHABILITATION: Medical Systems/Cognitive Engineering and Decision Making Joint Lecture Session [Lecture]
    65. MEDICAL SYSTEMS AND REHABILITATION: Human Factors Issues at the Point of Care
    66. MEDICAL SYSTEMS AND REHABILITATION: Ergonomic and Training Issues in Medical Systems Development [Lecture]
    67. MEDICAL SYSTEMS AND REHABILITATION: Medical Systems and Rehabilitation Posters
    68. PERCEPTION AND PERFORMANCE: Vigilance and Workload [Lecture]
    69. PERCEPTION AND PERFORMANCE: Motion and 3D [Lecture]
    70. PERCEPTION AND PERFORMANCE: Displays and Controls I [Lecture]
    71. PERCEPTION AND PERFORMANCE: Search and Attention [Lecture]
    72. PERCEPTION AND PERFORMANCE: Displays and Controls II [Lecture]
    73. PERCEPTION AND PERFORMANCE: Perception and Performance Posters
    74. PROFESSIONAL DEVELOPMENT: Articles
    75. SAFETY: Warnings and Risk Perception [Lecture]
    76. SAFETY: Safety Potpourri [Lecture]
    77. SAFETY: Safety Posters
    78. SPECIAL SESSION: Articles
    79. STUDENT FORUM: Articles
    80. STUDENT FORUM: Cutting-Edge Research by HFES Student Members [Lecture]
    81. SURFACE TRANSPORTATION: Articles
    82. SURFACE TRANSPORTATION: Lateral Control, Collision Avoidance, and Associated Icon Development [Lecture]
    83. SURFACE TRANSPORTATION: Driver Distraction Issues: Focus on Cell Phones and Telematics [Lecture]
    84. SURFACE TRANSPORTATION: Heavy Vehicles, Alertness, and Emergency Events [Lecture]
    85. SURFACE TRANSPORTATION: Surface Transportation Posters
    86. SYSTEM DEVELOPMENT: Articles
    87. SYSTEM DEVELOPMENT: Development and Application of Human Performance Models [Lecture]
    88. SYSTEM DEVELOPMENT: System Development Posters
    89. TEST AND EVALUATION: Test and Evaluation: Research, Tools, and Techniques [Lecture]
    90. TEST AND EVALUATION: Practitioner's Perspectives on Test and Evaluation [Lecture]
    91. TEST AND EVALUATION: Test and Evaluation Posters
    92. TRAINING: Training System Technology and Development [Lecture]
    93. TRAINING: Issues in Training Design and Evaluation [Lecture]
    94. TRAINING: Training Posters
    95. VIRTUAL ENVIRONMENTS: Articles
    96. VIRTUAL ENVIRONMENTS: Simulator Sickness [Lecture]
    97. VIRTUAL ENVIRONMENTS: Displays and Controls in Virtual Environments [Lecture]
    98. VIRTUAL ENVIRONMENTS: Navigation and Training in Virtual Environments [Lecture]
    99. VIRTUAL ENVIRONMENTS: Virtual Environments Posters

HFES 2002-09-30 Volume 46

AEROSPACE SYSTEMS: Information Display and Situation Awareness in the Cockpit [Lecture]

Does Workload Modulate the Difference Between Cockpit Traffic Display Formats BIBAFull-Text 1-5
  Amy L. Alexander; Christopher D. Wickens
Eighteen certified flight instructors from the University of Illinois Institute of Aviation participated in an experiment exploring the format of the Cockpit Display of Traffic Information for free flight traffic avoidance maneuvers. Pilots flew a sequence of flight scenarios to compare the effects of traffic load, display dimensionality (3D vs. 2D coplanar), and a vertical profile orientation on maneuver choice, conflict avoidance performance, and maneuver efficiency. The highest levels of workload induced more combined lateral/vertical maneuvers, degraded safety on the 2D coplanar displays, and degraded efficiency regardless of display type. In the context of an overwhelming preference for vertical maneuvers, the 3D display increased the frequency of the less-safe descent maneuvers (relative to climbs) and increased subjective workload, while the 2D rear-view display decreased the vertical efficiency of all maneuvers, relative to its side-view counterpart.
A Flight Simulator Usability Assessment of a Multi-function Flight-Planning and Navigation Display for General Aviation BIBAFull-Text 6-10
  Dennis B. Beringer; Jerry D. Ball
A human-factors and usability evaluation was performed on a beta version of a major manufacturer's flight-planning and in-flight navigation multifunction display in the Civil Aerospace Medical Institute's (CAMI's) Advanced General Aviation Research Simulator (AGARS), configured as a Piper Malibu (single-engine, complex aircraft). The evaluation was an open-ended process wherein data collection continued until consistent response patterns were uncovered. Data indicated general acceptance of the software package by the participating pilots. However, several recommendations for improvement arose from pilot consensus in the posttest questionnaire and interview that matched design criteria listed in a multifunction-display certification pocket guide being developed at CAMI. Changes to menu structure and data-entry logic were mentioned by nearly all of the participants, and included: navigation and route editing should occur on the same display page; a "back" or "undo" key is needed; and keys should be consistently placed across different pages. Findings are discussed in terms of cognitive loading, pilot expectations (stereotypes), and internal consistency.
Integrating Critical Information on Flight Deck Displays BIBAFull-Text 11-15
  Patricia May Ververs; Michael C. Dorneich; Michael D. Good; Joshua Lee Downs
Honeywell Laboratories has developed a concept for integrating multiple sources of data concerning information outside the aircraft. The concept, ANCOA (Alerting and Notification for Conditions Outside the Aircraft), was conceived as means for reducing error conflicts and establishing a clear prioritization among currently independent and disparate alerting systems for hazards external to the aircraft (e.g., TCAS, EGPWS). This paper documents an empirical evaluation of ANCOA by 12 professional pilots. The concept was evaluated in Honeywell Laboratories' Flight Simulation Laboratory in Minneapolis, Minnesota. Two core ANCOA features were manipulated and compared. The first was the integration of information by comparing ANCOA's integrated, overlaid features to a traditional display layout where the information was available on separate displays. The second variable was the categorization for incoming alerts (traffic, terrain, weather, scheduling constraints) by comparing alerts sorted by category to those without a category differentiation. Data support the integration of currently disparate systems onto a single display with performance requiring fewer pilot inputs and yielding lower workload scores. Categorization had little influence on pilot performance.
Comparing Pilots' Taxi Performance, Situation Awareness and Workload Using Command-Guidance, Situation-Guidance and Hybrid Head-Up Display Symbologies BIBAFull-Text 16-20
  John R. Wilson; Becky L. Hooey; David C. Foyle; Jennifer L. Williams
This study investigated pilots' taxi performance, situation awareness and workload while taxiing with three different head-up display (HUD) symbology formats: Command-guidance, Situation-guidance and Hybrid. Command-guidance symbology provided the pilot with required control inputs to maintain centerline position; Situation-guidance symbology provided conformal, scene-linked navigation information; while the Hybrid symbology combined elements of both symbologies. Taxi performance was assessed with average taxi speed and root mean square error (RMSE) from the centerline. Situation awareness and workload were assessed using a 3-Dimension SART and a 7-point scale, respectively. Taxi speeds were highest and RMSE from centerline lowest with Situation-guidance and Hybrid symbologies. Situation awareness was highest and workload lowest with Situation-guidance and Hybrid symbologies. These results are thought to be due to cognitive tunneling induced by the Command-guidance symbology. Situation-guidance (and Hybrid) HUD symbologies provided a common reference with the environment, which may have supported better distribution of attention.
General Aviation Pilot Training for Situation Awareness: An Evaluation BIBAFull-Text 21-25
  Cheryl A. Bolstad; Mica R. Endsley; Cass D. Howell; Anthony M. Costello
This study reports on efforts to improve situation awareness in general aviation (GA) pilots. Several training modules for enhancing skills that underlie the development of good SA were created and evaluated in a study with GA pilots. This paper describes the testing for two modules: contingency planning and preflight planning. These modules were developed to train higher order cognitive skills used in SA formation. Student pilots from Embry Riddle Aeronautical University participated in the study. The results from this test provide some evidence of a relationship between the two training modules and improvements in SA.

AEROSPACE SYSTEMS: Performance Enhancement in Aerospace Systems [Lecture]

International Space Station Robotic Systems Operations A Human Factors Perspective BIBAFull-Text 26-30
  Nancy J. Currie; Brian Peacock
Assembly and maintenance of the International Space Station (ISS) relies heavily on the use of extravehicular robotic systems. When fully assembled the ISS robotics complement will include three main manipulators, two small dexterous arms, and a mobile base and transporter system. The complexity and mobility of the systems and limited opportunities for direct viewing of the Space Station's exterior makes telerobotic operations an especially challenging task. Although fundamental manipulator design, control systems, and strategies for autonomous versus manual control vary greatly between the systems, commonality in the design of workstation controls and displays is considered essential to enhance operator performance and reduce the possibility of errors. Principal human factors opportunities are associated with workstation layout, human-computer interface considerations, adequacy of alignment cues for maintenance of safe approach corridors during mating tasks, spatial awareness challenges, integration of supplemental computer graphic displays to enhance operator global situational awareness, and training methodologies for preservation of critical skills during long-duration missions.
Display Integration Enhances Information Sampling and Decision Making in Automated Fault Management in a Simulated Spaceflight Micro-World BIBAFull-Text 31-35
  Bernd Lorenz; Francesco Di Nocera; Raja Parasuraman
Fault management (FM) performance and information sampling behavior were examined while participants operated a complex micro-world that simulated system failures within a generic life-support system of a spacecraft. One group of participants was supported by an integrated display that facilitated fault identification while the other group had to rely on separated raw data readings. The effects of two modes of intelligent automation support were also examined. At a low level of automation (LOA), fault identification was generated along with an advisory on a sequence of recovery actions to be implemented manually at the operator's discretion. The higher LOA generated fault identification but allowed the operator a veto against automatic implementation of the suggested recovery plan. Automated fault identification was unreliable 30% percent of the time; in these trials the automation missed fault identification, gave a false alarm to a nominal situation, or provided false or incomplete fault identification. Initiation of proper recovery when the automation failed was less accurate and slowest when operators were supplied with the non-integrated display, but only when they operated at the low LOA mode prior to the failure. This effect was associated with superior information sampling behavior at the higher LOA when automation was reliable. Display integration and the higher LOA thus supported more efficient sampling of fault relevant displays thereby, promoting better fault state awareness in the presence of reliable automation. This also benefited fault management when the automation failed.
An Operation Evaluation of ADS-B and CDTI during Airport Surface and Final Approach Operations BIBAFull-Text 36-40
  Vernol Battiste; Nancy H. Johnson
The availability of new technologies for both the flight deck and air traffic control facilities is creating new capabilities for enhanced aircraft operations. With the introduction of these new technologies comes a need to evaluate their effectiveness in both laboratory and operational settings. Two such technologies, Automatic Dependent Surveillance-Broadcast (ADS-B), and Cockpit Display of Traffic Information (CDTI) with and without a surface map, were demonstrated during an Operational Evaluation in the Ohio Valley. The main focus of the study was a comparison of flight crew navigational performance, traffic, and runway occupancy awareness, with and without a surface map on their CDTI displays during airport surface and final approach operations. Sixteen commercial, government, corporate, and general aviation crews participated in the evaluation, flying a variety of aircraft ranging from Boeing 727s to the Piper Aztecs. Aircraft GPS track position data, in flight observer reports, post-flight structured interviews, and post-flight questionnaires were used to support data collection. Flight crews reported that the CDTI enhanced their situational and traffic awareness. They also reported that when the CDTI included a surface map, surface navigational and traffic awareness were further enhanced. Pilots also reported that utilizing the CDTI did not interfere with other cockpit tasks. Finally, the addition of a surface map enhanced flight crews' awareness of runway status. These findings suggest that system efficiency and safety will be enhanced with the introduction of a CDTI which includes airport surface maps.
Asynchronous Communications to Support Distributed Work in the National Airspace System BIBAFull-Text 41-45
  Roger J. Chapman; Philip J. Smith
This research involved the evaluation of a multimodal asynchronous communications tool to support collaborative analysis of post-operations in the National Airspace System (NAS). Collaborating authors have been shown to provide different feedback with asynchronous speech based communications compared to text. Voice synchronized with pointing in asynchronous annotation systems has been found to be more efficient in scheduling tasks, than voice-only, or text only communication. This research investigated how synchronized voice and pointing annotation over asynchronously shared slide shows composed of post operations graphical and tabular data differs in its effect compared to text based annotation, as collections of flights ranked low by standard performance metrics are discussed by FAA (Federal Aviation Administration) and airline representatives. The results showed the combined problem solving and message creation time was shorter when working in the voice and pointing mode than the text based mode, without having an effect on the number and type of ideas generated for improving performance. In both modes the system was also considered useful and usable to both dispatchers and traffic managers.
Joint Shipboard Helicopter Operations: Human Factors Issues and Challenges BIBAFull-Text 46-50
  John W. Ruffner; John E. Padukewicz; John D. Meier
As part of the US military's Joint Force initiative, non-Navy helicopters are increasingly required to conduct operations on Navy ships. Consequently, shipboard helicopter interoperability has become a requirement for all the military forces. Key shipboard helicopter operations include: landings and takeoffs, launch and recovery support activities, ordnance handling, refueling, and external load operations. These operations involve a variety of helicopter types from the different services on all aviation-capable Navy ships, in different sea states, and under changing visibility and environmental conditions. The requirement for shipboard helicopter interoperability involves several unique human factors issues and poses many challenges. In this paper, we discuss the major issues and challenges as they relate to three broad categories: procedures, training, and compatibility. We identify areas where human factors specialists can make significant contributions to improve the effectiveness and safety of shipboard helicopter operations. In addition, we identify opportunities for future research.

AEROSPACE SYSTEMS: Air Traffic Control and Traffic Flow Management [Lecture]

Electro-Optic Sensors to Aid Tower Air Traffic Controllers BIBAFull-Text 51-55
  Dino Piccione; William K. Krebs; Penny Warren; Ron G. Driggers
Background: Tower air traffic controllers separate aircraft to assure safety and expedite the flow of traffic. During poor visibility (e.g., fog) the aircraft landing and departure rate decreases significantly which can result in flight delays. The purpose of this study was to investigate the feasibility of using electro-optic sensors to enhance tower controller visual capabilities during poor atmospheric or low-illumination conditions. Methods: Day and nighttime visible, mid- and long-wave infrared digital imagery were collected at an airfield. To validate the collected imagery, a human-in-the-loop analytic model was used to predict an average military observer's visual discrimination of a target on the airport surface. Results: The field data collection and model results found that electro-optic sensors, in particular long-wave infrared, improved operators nighttime detection, recognition, and identification of targets on the airfield surface. Conclusions: Actual or potential applications of this research include integrating electro-optic sensors into the tower to improve aircraft movement during poor visibility.
The Impact of Communication Delays on Air Traffic Controllers' Vectoring Performance BIBAFull-Text 56-60
  Esa M. Rantanen; Jason S. McCarley; Xidong Xu
An experiment was conducted to investigate the impact of communication delays in the pilot-controller communication loop on air traffic controllers' performance and workload. Four levels of constant systemic audio delay (AD), 150, 250 ms, 350 ms, and 1,000 ms, and two levels of variable pilot delay (PD), zero delay and realistic delay, were employed. Vectoring accuracy and the controller's final turn initiation served as dependent variables. Subjective workload was measured by the NASA-TLX workload index. Eight subjects proficient in the task participated in the experiment. Random PD had significant effects on both vectoring accuracy and final turn initiation; accuracy was reduced and initiation times were earlier when PD was added. However, data showed no effect of AD on vectoring accuracy, and no evidence of compensatory strategies in response to increasing AD levels. Results suggest that variability in the subjects' turn initiation effectively masked the impact of even the longest AD of 1,000 ms on vectoring accuracy. The NASA-TLX showed no effect of AD on workload in either PD condition.
Effects of the Controller-to-Pilot Data Link (DATALINK) on Crew Communication BIBAFull-Text 61-65
  Craig M. Harvey; Mike Reynolds; Andrea L. Pacley; Richard J. Koubek; Albert J. Rehmann
This paper discusses a Federal Aviation Administration (FAA) manned simulation study that investigated the effects of Controller-to-Pilot Data Link (datalink) on crew communications. Professional pilots participated in high fidelity simulation tests where crews received Air Traffic Controller (ATC) messages through the datalink. The results were compared to a similar study conducted where crews only communicated by radio to controllers. Results demonstrate that the nature of crew communications within the flight deck do change because of datalink. Unlike in the past where crews became aware of ATC communications at the same time through their headsets, new communication types are now needed due to the shift from ATC radio communications to ATC datalink messages. Thus flight crews must keep each other aware of information passed through the datalink. The frequency of communication was found to be significantly different depending on the location of the datalink on the flight deck. In addition, datalink crews experienced significantly less ATC radio transmissions as expected; however, the within crew communication related to datalink increased. When within crew datalink communication and the ATC radio communication are combined, one finds that ATC related communication is significantly higher in datalink crews as compared to traditional radio crews. This study illustrates the need to fully evaluate the impact new technology has on flight crews and their communication process.
The Effect of Predictive Aid Usage on Controller Strategies Mental Demand under Direct Routing BIBAFull-Text 66-70
  Ashley Nunes; Michael L. Matthews
The implementation of Free Flight, a strategic goal for improving air traffic capacity in the National Airspace System, has raised many concerns amongst controllers regarding safety. A principal concern is the inability of the controller to project future aircraft states due to increased levels of mental workload and breakdowns in situation awareness. This paper looks at a by-product of the Free Flight concept, namely Direct Routing. It proposes a modified interface, which is representative of a combined data-link and conflict detection aid that would help in giving predictability back to the controller. Results showed that the aid served to ameliorate the effects of high airspace load on mental demand under an analogue of Direct Routing conditions. The results also highlight how controller strategies can vary when dealing with a variety of requests for routing changes. The implications of these results are discussed.
Investigating Delegation of Spacing Tasks from Air Traffic Controllers to Pilots. Impact on Controller Activity. BIBAFull-Text 71-75
  Laurence Rognin; Karim Zeghal; Isabelle Grimaud; Eric Hoffman
Controller-in-the-loop experiments were conducted in order to assess the impact on air traffic controller activity of the delegation of spacing task to the flight deck. Three experiments involving a total of 18 European controllers during 7 weeks took place over the past two years. In addition to standard data analysis, a geographical-based analysis was introduced. It consisted in analysing the distribution of manoeuvring instructions and eye fixations as a function of their distance to the sector exit. This analysis confirmed assumptions that delegation leads to anticipate the building of the sequences, and to relieve the controller of maintaining these sequences. Although these initial results suggest a positive impact on controller activity, they still need to be complemented, typically with contextual analysis of monitoring through microscopic analysis of eye fixations.
Space Human Factors Advanced Development Projects BIBAFull-Text 76-80
  B. Woolford; T. Rathjen; M. Whitmore; S. Rajulu; J. Blume Novak; J. McCandless; B. Peacock; R. Prouty; R. Burnett; C. Booher; R. Ortiz; M. Segal; K. Smart; J. Gonzales; M. Dhutia; D. Ngyuen; S. Vallance; E. Morphew; D. Balmer; S. Ramsey; V. Byrne
The NASA Space Human Factors community engages in activities that range from basic research through advanced development projects to applications associated with ongoing programs such as the International Space Station and the Shuttle. This panel of NASA human factors specialists will present information relating to advanced development projects aimed at the creation of tools that can be applied to the analysis, design and evaluation of space vehicles and operations, and future space vehicle design concepts. The projects are: "The voice of the customer" -- a description of the multiple pathways used to obtain astronaut information and opinion; International Space Station emergency medical procedure evaluation and redesign; the "magic windows" project which provides a multifunctional display system for operations and personal use on space vehicles and analogs; analytical approaches to digitally scanned crew member anthropometric data; crew member activity measurement, modeling and scheduling; evaluation of the upgraded displays of the Space Shuttle cockpit; and finally a description of the updated, electronic version of the space human factors engineering database.

AEROSPACE SYSTEMS: Decision Making in Aviation [Lecture]

Relating Flight Experience and Pilots' Perceptions of Decision-Making Skill BIBAFull-Text 81-85
  Juliana Goh; Douglas A. Wiegmann
Relationships between flight experience and pilots' perceptions of their ability to perform various aspects of the decision-making process were examined in the present study. Pilots were asked to rate how good they were, compared to the average General Aviation pilot, at monitoring, recognizing, diagnosing, generating solutions and implementing solutions when encountering flight path deviations, changes in weather conditions, mechanical malfunctions and conflicting traffic. Numerous measures of flight experience were collected. Results indicate that more experienced pilots felt that they were better at recognizing problems and implementing solutions, however, they did not necessarily feel more confident in their abilities to diagnosis the underlying causes of the problems. The results have implications for aeronautical decision making theories in general, and the design of flight training curricula in particular.
Priorities of Weather Information in Various Phases of Flight BIBAFull-Text 86-90
  Dennis B. Beringer; Roger Schvaneveldt
Questionnaire data were obtained from 71 pilots, some categorized as novice pilots and others as experienced pilots according to overall flight hours. The form required the participants to rank various items of weather information by phase of flight on a scale of relative importance. Responses indicated that both novice and experienced pilots rank weather factors similarly with a few exceptions, that many factors' ratings vary considerably by phase of flight, and pilots having more experience tend to rate weather information factors as being more important overall than do those having less experience. The data may be useful in establishing prioritization schemes for the presentation of weather data in the cockpit, particularly in the context of multifunction displays.
Change Detection after Preliminary Flight Decisions: Linking Planning Errors to Biases in Plan Monitoring BIBAFull-Text 91-95
  Emily K. Muthard; Christopher D. Wickens
The present study investigated a link between plan continuation errors and plan monitoring. Pilots were asked to execute a flight plan that traversed through hazardous airspace and then monitor the success of the plan by seeking and detecting changes in the airspace that could affect the safety of the plan. Following change detection, pilots had the opportunity to revise these plans. In nearly one-third of trials, pilots failed to revise flight plans, thereby committing a plan continuation error, and were more likely to do so when plan monitoring was inadequate. Overall, more than half of changes went undetected, though detection response times were improved when changes were relevant to the flight planning task or when traffic aircraft were changed rather than weather systems. Findings imply that plan monitoring is less than perfect, which may be a substantial contributing factor to plan continuation errors.
Training Pilots to Prioritize Tasks BIBAFull-Text 96-100
  Saher Bishara; Ken Funk
The purpose of this study was to develop and evaluate the effectiveness of a technique to help pilots prioritize tasks. A part-task simulator experiment was conducted in which three groups of general aviation pilot participants flew pre- and post-training flights. Participants in two groups received task prioritization training between the flights while those in a control group did not. Task prioritization error rates and prospective memory error rates from pre- and post-training flights were compared. Task prioritization and memory error rates improved in the training groups and did not improve in the control group. However, these findings must be considered preliminary, as several issues remain to be resolved by follow-on studies.
Tactical vs. Strategic Behavior: General Aviation Piloting in Convective Weather Scenarios BIBAFull-Text 101-105
  Kara A. Latorella; James P. Chamberlain
We commonly describe environments and behavioral responses to environmental conditions as "tactical" and "strategic." However theoretical research defining relevant environmental characteristics is rare, as are empirical investigations that would inform such theory. This paper discusses General Aviation (GA) pilots' descriptions of tactical/strategic conditions with respect to weather flying, and evaluates their ratings along a tactical/strategic scale in response to real convective weather scenarios experienced during a flight experiment with different weather information cues. Perceived risk was significantly associated with ratings for all experimental conditions. In addition, environmental characteristics were found to be predictive of ratings for Traditional IMC (instrument meteorological conditions), i.e., aural weather information only, and Traditional VMC (visual meteorological conditions), i.e., aural information and an external view. The paper also presents subjects' comments regarding use of Graphical Weather Information Systems (GWISs) to support tactical and strategic weather flying decisions and concludes with implications for the design and use of GWISs.

AEROSPACE SYSTEMS: Information Displays and Decision Support in Aviation Systems [Lecture]

Incorporating Procedural Information in a Paired Approach Task BIBAFull-Text 106-110
  Steven J. Landry; Amy R. Pritchett
This study focused on pilot performance at simultaneously flying simulated instrument approaches and self-separating from an aircraft on approach to a closely spaced parallel runway. The participant pilots flew approaches on Georgia Tech's Reconfigurable Flight Simulator and were instructed to remain within the "safe zone" -- an area in which the subject aircraft was safe from collision danger and wake vortices from the other aircraft -- as depicted on their navigation display. Two underlying bases for calculating the safe zone were used: a "predicted" safe zone utilizing procedural information, and an "actual" safe zone utilizing real-time information. No display effects were found for pilot performance or behavior, despite the very different implications of the two safe zone depictions. Also, pilots monitored the other aircraft closely for compliance, but could not recognize the implications of noncompliance for their own approach. This suggests that pilots have a particular, persistent, and perhaps poor, strategy for this task.
The Effects of an Airborne Inter-Arrival Spacing Tool on Pilot Workload and Acceptability BIBAFull-Text 111-115
  Katrin G. Helbing; Todd Eischeid; Rosa M. Oseguera-Lohr
An airborne inter-arrival spacing tool was developed by NASA Langley Research Center to aid pilots in maintaining a time-based spacing interval behind another aircraft in the arrival sequence. A number of display features, including numeric speed commands, a speed pointer on the Fast/Slow Indicator, and graphical depiction of the desired aircraft position on the navigation display, were developed to assist pilots in maintaining the proper speed to achieve the required spacing interval. Because the use of such automated tools requires the acceptance of the user population, a study was conducted to assess the impact on user workload and acceptability. The tool was tested in a full-task simulation in a Boeing-757 full-mission, fixed-base simulator. Subject pilots were paired with a confederate pilot to complete tasks in both the pilot flying and pilot not flying positions. This paper presents the subjective evaluations of the inter-arrival spacing tool. The qualitative workload data from eight current B-757 airline pilots are compared from the perspectives of tool usability and acceptability, and the ability to attain and maintain the appropriate time interval spacing. Results of the study indicate that the pilots who participated in the study were comfortable using the Advanced Terminal Area Approach Spacing (ATAAS) tool and were confident in the automated spacing guidance that the tool provided. The ATAAS tool did not increase perceived pilot workload as compared to an approach conducted under standard (current-day) conditions.
Ecological Interface Design in Aviation Domains: Work Domain Analysis and Instrumentation Availability of the Harvard Aircraft BIBAFull-Text 116-120
  Roshanak Moradi Nadimian; Scott Griffiths; Catherine M. Burns
This paper applies Work Domain Analysis (WDA) to the aviation domain. We developed a two-dimensional work domain model of the Harvard aircraft as the primary phase of our Ecological Interface Design (EID) process.. In contrast to previous work, we modelled the entire aircraft as the work domain. The work domain analysis was followed by an instrumentation availability analysis. We developed a model for the variables derived from the WDA to classify the state of those variables according to their availability and measurement. We also have the opportunity, in our future work, to flight test the ecological displays, something that has not occurred before.
The Effect of Visual Location on Cognitive Tunneling with Superimposed HUD Symbology BIBAFull-Text 121-125
  Susan R. Dowell; David C. Foyle; Becky L. Hooey; Jennifer L. Williams
Cognitive tunneling occurs when the pilot's attention becomes locked on non-conformal, superimposed head-up display (HUD) symbology, while neglecting to scan the out-the-window scene, as a result of locating the HUD symbology near (in visual angle) the outside scene information (Foyle, McCann, Sanford & Schwirzke, 1993). Previous studies have shown that cognitive tunneling could be eliminated by placing the HUD symbology at least 8 deg from the out-the-window path being tracked. Limitations to previous research have included experimental designs that tested participants in multiple HUD information locations without fostering an efficient eyescan strategy for any one HUD location. Experiment 1 dedicates a participant to a single HUD location with blocked presentation. The results indicate that cognitive tunneling is not only eliminated by placing HUD symbology greater than 8 deg, but path tracking performance improves with symbology placed in an upper location on the HUD. Experiment 2 shows that the resulting performance decrement when information is overlaying the path (0 deg) may be associated with symbology compellingness, regardless of symbology relevance to the task.
Cardiac and Eye Activity Correlates of Sleep Loss in Helicopter Pilots BIBAFull-Text 126-129
  Glenn F. Wilson; John A. Caldwell
The effects of one night's sleep loss on helicopter pilot's psychophysiology were investigated. This was done to determine if cardiac and eye measures were sensitive to sleep loss during actual flights. Because of the potentially catastrophic errors that can occur when sleep deprived reliable measures to detect this state are needed. If the deleterious effects of sleep loss can be determined prior to performance break down then it should be possible to devise systems to avoid accidents. Ten pilots flew a standard 1.5 hour scenario three times with increasing hours of sleep loss. Heart rate, heart rate variability and eye blink rate were recorded during the three flights. Heart rate and heart rate variability demonstrated statistically significant effects as the sleep loss increased. Heart rate variability declined, especially during the most difficult fight maneuvers at the highest levels of sleep deprivation.

AEROSPACE SYSTEMS: Understanding and Enhancing Human Performance in Aviation [Lecture]

Gz Acceleration Loss of Consciousness: Time Course of Performance Deficits with Repeated Experience BIBAFull-Text 130-134
  Lloyd D. Tripp; Joel S. Warm; Gerald Matthews; Peter Y. Chiu; John E. Deaton; William B. Albery
Pilots of modern fighter aircraft encounter episodes of gravity-induced loss of consciousness (GLOC) consisting of complete unconsciousness and subsequent confusion. According to Whinnery, Burton, Boll, and Eddy (1987), pilots are totally incapacitated for 24 sec during such episodes. Using centrifuge simulators to induce GLOC and math and tracking tasks to emulate flight performance, this study confirms the duration of total incapacitation described by Whinnery et al. (1987) and also indicates that the GLOC problem is more serious than they envisioned. Performance efficiency deteriorates from 3.20 to 7.44 sec prior to the onset of unconsciousness and does not return to baseline levels until 55.5 sec after the confusion phase has ended. Thus, at speeds of 500 mph typical of modern fighters, pilots can travel 12.1 miles while not in control of their aircraft. These effects do not appear to be reduced by repeated encounters with GLOC.
NASA Synthetic Vision EGE Flight Test BIBAFull-Text 135-139
  Lawrence (Lance) J. Prinzel; Lynda J. Kramer; J. Raymond Comstock; Randall E. Bailey; Monica F. Hughes; Russell V. Parrish
NASA Langley Research Center conducted flight tests at the Eagle County, Colorado airport to evaluate synthetic vision concepts. Three display concepts (size "A" head-down, size "X" head-down, and head-up displays) and two texture concepts (photo, generic) were assessed for situation awareness and flight technical error / performance while making approaches to Runway 25 and Runway 07 and simulated engine-out Cottonwood 2 and KREMM departures. The results of the study confirm the retrofit capability of the HUD and Size "A" SVS concepts to significantly improve situation awareness and performance over current EFIS glass and non-glass instruments for difficult approaches in terrain-challenged environments.
Peripheral Arterial Tone as an On-Line Measure of Flight Load BIBAFull-Text 140-144
  Cristina Iani; Daniel Gopher; Arthur J. Grunwald; Peretz Lavie
We investigated variations in continuous and discrete flight demands in a simulated flight mission employing a novel physiological measure of invested effort, Peripheral Arterial Tone (PAT).
   Twelve male subjects performed a computer-simulated agricultural flight task. They were required to fly over a specific lane of a field (continuous task) and change lanes in response to flags, which were presented at varying intervals (discrete task). The difficulty of the flight task was manipulated by changing the plane control (single- vs. dual-axis control), while the difficulty associated with the discrete events was manipulated by varying the amount of lateral change signalled by the flag (no change vs. 1.5 or 3 lanes of change).
   PAT amplitude values were lower in the difficult level of the continuous task and was further attenuated following the appearance of the flag when a change in the flight position was required.
Pilot Error in Copying Air Traffic Control Clearances BIBAFull-Text 145-149
  Esa M. Rantanen; Nina K. Kokayeff
A study investigating the accuracy of pilots' copying air traffic control clearances is described. Twenty-four airline pilots listened to 28 taped clearances and copied them down on an answer sheet using shorthand, longhand, or some combination of these according to their preferences. The copied clearances were analyzed by the number of correctly copied elements, the number of omitted elements, and the number of extraneous elements that were not present in the original clearance. Preliminary results indicate a strong influence of habit and familiar operating environment and procedures on the accuracy of copying unfamiliar information. Common errors included victor-airways copied as jet-airways, low altitudes copied as much higher, and slow speeds copied as much higher. The vulnerability of controller-pilot communications to the effects of unfamiliarity is apparent. A detailed analysis of these data may provide for a better understanding of the shortcomings of controller-pilot communication.

AEROSPACE SYSTEMS: Aerospace Systems Posters

CRCT (Collaborative Routing Coordination Tools) and TFM (Traffic Flow Management) Decision Support Tool Prototyping BIBAFull-Text 150-154
  Anthony J. Masalonis
This paper summarizes several years of Traffic Flow Management (TFM) R&D work. The MITRE Corporation's Center for Advanced Aviation System Development (CAASD) has been engaged in a long-term research program to define and refine decision support concepts and capabilities for TFM, the branch of Air Traffic Management that manages the strategic aspect of air traffic by balancing airspace capacity with demand, especially during severe weather or heavy traffic. This paper describes CAASD's work on the concept of Collaborative Routing, in which all affected parties -- Federal Aviation Administration (FAA) and aircraft operators -- can share in realtime a common picture of TFM problems and potential solutions. The Collaborative Routing Coordination Tools (CRCT) refers to a set of functionalities that support Collaborative Routing, and also to a software platform developed and used by CAASD to conduct the R&D. In this paper, the Collaborative Routing concept is described, and sample user interfaces supporting the concept are presented. Evaluations with operational personnel are described at a high level. Capabilities developed and refined via this work include the FCA (Flow Constrained Area), and the reroute modeling capability. These functions allow the user to evaluate the impact of a rerouting solution to controllers and airspace users (airlines and other pilots), before implementing that solution. Finally, ongoing research on future TFM decision support capabilities is described.
An Analysis of In-Flight Impairment and Incapacitation in Fatal General Aviation Accidents (19901998) BIBAFull-Text 155-159
  Narinder Taneja; Douglas A. Wiegmann
In-flight impairment and incapacitation are defined as states wherein the pilot's ability to effectively control the aircraft is adversely affected. They are of special concern in general aviation given there may be no second pilot to take over the controls. The purpose of the present study was to examine the characteristics of fatal general aviation accidents associated with impairment and incapacitation. A comprehensive review of 2,696 fatal general aviation accidents from 1990-1998 using database records maintained by the NTSB and FAA yielded 216 accidents (8.01%) that had some form of impairment/incapacitation or physiological causes mentioned in the accident report. Impairment due to drugs (n = 88, 40.7%) and alcohol (n = 68, 31.5%) were the most common causes. Cardiovascular causes were cited in 12.03% (n = 26) of the cases. Significant relationships were observed between age and impairment/incapacitation due to alcohol, drugs, and cardiovascular causes. Some disparities were observed between the prevalence of alcohol in toxicology samples and alcohol impairment being cited in the accident report as a contributory factor. The analysis provides some insight into the possible causes of pilot impairment and incapacitation in general aviation. Education and risk management training may serve as effective interventions.
Human Factors in Aircraft Accidents: A Holistic Approach to Intervention Strategies BIBAFull-Text 160-164
  Narinder Taneja
Human error has been implicated in almost 70-80% of civil and military aviation accidents. It appears that attempts to understand human factors in aircraft accidents and apply remedial strategies have been made in isolation in addressing a particular link in the whole process of aircraft accident prevention. The suggested holistic approach to minimize aircraft accidents, aims to provide a composite and macroscopic view of the activities within the aviation environment that can be targeted to produce the desired results. It also provides a microscopic look at possible domains within each link. Targeting one particular aspect or link in the entire process may or may not influence the other components in the loop. Such an approach would address the experience and certainty of safety investigators with regards to contribution of human factors in aircraft accidents and the understanding of temporal relation between various human factors at one end to issues of intervention strategies based on sound human factors principles and a follow up evaluation of the impact of these intervention strategies on the other end. The influence of safety culture in integrating the diverse components of the accident prevention program is highlighted.
Perceptual Aspects of Symbol Shapes and Relations in 3D Aircraft Displays BIBAFull-Text 165-169
  Patrik Andersson; Torbjorn Alm
This report presents two experiments in the area of perspective aircraft displays. The focus was to understand symbolic and symbol relations in the 3D environment. In the first experiment, subjects' ability to distinguish five different aircraft symbol shapes was investigated together with the perception of their heading in the 3D space. The perspective used in this experiment was egocentric. The second experiment investigated the judgment of the spatial relation between an own-ship symbol and a target symbol. Thus, in this case the perspective was exocentric and two aspect angles were used for the camera position. Both experiments were carried out in non-dynamic scenarios. The display character was topographic with a superposed grid on the ground surface. The overall conclusion from the experiments is that judgments of azimuth and elevation are very difficult in these static scenarios. Also, symbol recognition of 3D pictorial symbols is problematic for complicated symbol shapes, depending on different appearances for various symbol headings in the 3D space.
Imaging Systems in Search and Rescue: Implications for Geographic Orientation BIBAFull-Text 170-174
  Jocelyn Keillor; Karen J. Hodges; Michael Perlin; Nada Ivanovic; J. G. Hollands
Optical imaging systems have the potential to dramatically change the task of a search and rescue technician. An important difference between the traditional process of "looking out the window" and search conducted with the aid of an optical imaging system is that in the case of imaging systems the frame of reference for the viewed display is de-coupled from the technician's frame of reference. We examined the ability of a moving-map display that recorded the locations of designated targets to support geographic orientation in operators with and without knowledge of the modeled terrain. Participants who did not have knowledge of the terrain benefited from the moving map, as when it was present they were less likely to re-identify targets that they had already viewed, whereas those who were already familiar with the terrain model showed no benefit from this manipulation. Both groups had difficulty localizing targets on a map following flight, and the two groups did not differ in their ability to initially detect targets using the system.

AGING: Older Adults and Computer Systems [Lecture]

Age and Perceptions of Usability on Telephone Menu Systems BIBAFull-Text 175-179
  Christopher Reynolds; Sara J. Czaja; Joseph Sharit
The objectives of this study were to determine if older adults encounter difficulty using real-world telephone menu system applications and to gather data on the usability features of these systems. Six real-world telephone menu systems, which varied in complexity and function, were examined. The sample included 32 community dwelling adults ranging in age from 18-80 years. Participants interacted with the menu systems to perform a sample set of tasks. They were also asked to rate the usability features of the system in terms of their goodness and their relative importance. The data indicated that in addition to taking longer, the older adults tended to have more difficulty performing the tasks. The findings also indicated that memorability was an important usability feature, and that the ratings of overall usability and overall satisfaction were significantly worse for the older adults.
An Application of Neural Network Modeling to Diagnose Eating Behavior of Seniors in Smart Houses BIBAFull-Text 180-184
  Jiyoung Kwahk; Robert C. Williges; Tonya L. Smith-Jackson
The concept of a Smart House has received research and consumer attention as a promising solution to provide safe and independent living for an aging population. These benefits can be enriched with the incorporation of Senior Healthwatch, a home health monitoring system that collects data from the sensors installed in the house and provides critical information about the residents' health condition during their daily activity. This study introduces a neural network modeling approach combined with cluster and decision tree analyses as a means to develop the inferential logic of Senior Healthwatch. Its role is to convert the data obtained from the Smart House into more meaningful information about the residents' daily activity such as the times for meal preparation, eating, and cleaning. The results of this study can become a major feature in the Smart House technology.
Comparing Older and Younger Adults' Traversal Time in Expandable and Non-Expandable Hierarchical Structures BIBAFull-Text 185-188
  Sri Hastuti Kurniawan; R. Darin Ellis; Panayiotis Zaphiris
The present study investigates time and click error differences when older and younger computer users traversed expandable and non-expandable online hierarchical information structures to reach a target. The results show that older users were slower but did not make more errors than their younger counterparts, suggesting more cautious decision making. The study did not show superiority of either hierarchy in terms of traversal time but the expandable hierarchy resulted in fewer errors to get to the target. Although older users significantly rated their computer and Internet experience lower than younger participants, experience did not alter the significance of age and hierarchy differences.
An Age-Related Comparison of a Touchscreen and a Novel Input Device BIBAFull-Text 189-192
  Richard Pak; Anne C. McLaughlin; Chao-Chung Lin; Wendy A. Rogers; Arthur D. Fisk
Interaction with almost any technical system requires the user to use an input device. Typically, the most common input device for a computer has been the mouse. However, the mouse presents challenges to a large segment of a potential user population: older adults. The current study examines potential performance differences in two types of input devices. The first, a touchscreen, is a direct input device that requires almost no training to use. The second, a rotary encoder, is a novel input device that is being used more frequently in consumer devices but has received little to no research attention. The current results suggest that choice of input device is highly related to the type of interface (what elements make up the interface) and age. Both age-dependent and age-independent guidelines are provided to address interface and input device interactions to positively affect usability.
Promoting Successful Computer Use by Older Adults: Input Devices and Experienced Users BIBAFull-Text 193-196
  Patricia Holley; Neil Charness
This experiment looked at the use of two input devices (mouse and light pen) for younger, middle-aged, and older adults who were experienced mouse users. We asked participants to use both their preferred and non-preferred hand to perform a pure pointing task and then to rate the ease of use and acceptability of the device they were using in the hand they were using it as well as their perceived work load across trials. We found that using a light pen minimized age differences, that differences between the preferred and non-preferred hand became more apparent with age so that older adults were less efficient using their non-preferred hand than were younger adults, and that older adults gained more from practice. Overall, the mouse was rated as more acceptable than the light pen across trials even though the light pen was more efficient. Finally, recommendations are made for ease of use, acceptability, and performance.

AGING: Aging and Everyday Applications [Lecture]

Acceptable Cap Torques for Processed Food Containers for Aged Women BIBAFull-Text 197-200
  Kwan S. Lee; Seung H. Shin; Byung C. Shon
The objectives of this study are to measure the twisting strength of aged women for different types of caps and to determine the acceptable torque of the caps of processed food containers for aged women. An experiment was conducted in the laboratory to find twisting strengths (torque) of young and aged people and the required torques to open various caps of processed food containers using a torque measurement device. Fifty nine young women who were in the range of twenty to thirty years old and fifty aged women who were in the range of sixty to seventy years old participated as subjects. Seventeen processed food containers which were categorized into three types based upon diameters were used for measurements. It was found that the torque required to open caps of containers needs to be within 74 N cm for pilfer proof caps with the diameter of 25mm to 30mm, 141 N cm for twist-off caps with the diameter of 40mm and 214 N cm for screw caps with the diameter of 65mm to 75mm. Aged women's twisting strengths were only 62.9% of young women's twisting strengths. It was also found that aged women had difficulty in opening 58.9% of processed food caps in use.
The Impact of Organizational Structure and Labels on Web Usability for Older Adults BIBAFull-Text 201-205
  Julian Sanchez; Sara J. Czaja
One of the key aspects of the success of an e-commerce web site is the consistency between the design of the site and the expectations and knowledge of the user population. The objective of this study was to examine the impact of information organization and label quality on user performance and satisfaction. The study employed a two (information organization: goalcentered organization versus a product-centered organization) by three (label quality: high, medium, low) factorial design. Study participants included 60 persons aged 60+ years. Participants were required to find six products while shopping in a simulated health store web site. Results revealed that higher quality labels and goal-centered organization resulted in higher levels of performance and satisfaction. Data of this type can be used to help develop web design guidelines for older adults.
Staying Oriented While Driving BIBAFull-Text 206-208
  S. N. de Ridder; C. Elieff; A. Diesch; C. Gershenson; H. L. Pick
Do elderly drivers have more trouble finding their way and staying spatially oriented than younger drivers do? If spatial orientation is more difficult for elderly drivers it could distract attention from vehicle control resulting in a higher accident rate for elderly drivers. Moreover, it could become less desirable for older drivers to explore unfamiliar surroundings and as such diminish their action radius. In order to test our hypothesis that elderly drivers have more problems with wayfinding and spatial orientation drivers in two age groups were asked to perform a wayfinding task in an unfamiliar environment. Errors in orientation were measured and compared between age-groups. Results on this driving and wayfinding task support the original hypothesis that acquiring and maintaining spatial orientation is significantly more problematic for elderly than younger drivers, hence could be a distracting factor for vehicle control.
Web Site Design for the Disabled: Issues for Human Factors Practitioners BIBAFull-Text 209-213
  Sarah J. Swierenga
Enhancing sites for accessibility allows disabled customers to interact effectively with web products using screen readers, voice browsers, TTY, etc. Human Factors practitioners must address several issues: obtaining a fundamental understanding of the various types of disabilities and the implications for design and testing, learning how to apply the Section 508 standards to design accessible web sites, and deciding on an approach to integrate accessibility compliance efforts into the product design and development process.

AGING: Aging Posters

Effects of Reduced Contrast on Young and Older Adults' Utilization of Context During Reading BIBAFull-Text 214-218
  Tracy L. Mitzner
People frequently read in sub-optimal conditions (Charness & Dijkstra, 1999). When text is difficult to perceive, readers can rely on sentential context as a compensatory strategy. Specifically, readers can develop expectations about which words will occur in a text based on the context in which words occur. The purpose of this study was to examine age differences in the use of contextual utilization, by comparing words that were highly predictable from their sentence context to words that were less predictable from their sentence context. Text was presented in three different levels of text/background contrast (high, medium, low) to explore the effects of contrast reduction. Eye tracking was used to measure fixation times to target words. Readers, particularly older adults, fixated low-predictability words longer than high-predictability words. Contrast reduction did not significantly influence reading times for either group, suggesting that readers are tolerant of some forms of stimulus quality degradation.
A Study of Interaction Devices and WWW User Interface Design for Older Adults BIBAFull-Text 219-223
  Pei-Luen Patrick Rau; Jia-Wen Hsu
This study investigates the effects of interaction devices on performance of using WWW user interface for older users, and ways to design appropriate user interfaces to enhance browsing and searching performance for older users. Two experiments were designed and conducted to test two hypotheses, that for older novice users, browsing and searching performance and attitudes will be better with a direct manipulation devices rather than with indirect manipulation device. The results indicated that older users using touch screen were faster and less frustrated than older users using voice control and mouse. Moverover, older users using touch screen were faster and less frustrated than older users using voice control and mouse, and older users using mouse and keyboard were less frustrated than older users using voice control.

COGNITIVE ENGINEERING AND DECISION MAKING: Articles

National Differences and Naturalistic Decision Making BIBAFull-Text 224
  Helen Altman Klein
Naturalistic decision making is grounded in a rich body of cognitive research. Cognitive research, however, has been undertaken primarily by scientists from the United States, Northern Europe, and English speaking nations with subjects from these same nations. The value of the research for predicting the naturalistic decision making of other national groups depends on the generality of the research findings. Cognitive processes are universal only if they are independent of the national origins of the researchers and the subjects.
Barriers to Adaptability in a Multinational Team BIBAFull-Text 225-229
  Linda G. Pierce
The majority of current military missions require collaboration among multiple nations. For example, the military presence established in Bosnia-Herzegovina (B-H) following the end of their civil war included participants from over 38 nations. U.S. Army forces were assigned to the headquarters element and to Multinational Division North (MND(N)). We reviewed processes of the U.S. Army force commanding MND(N) to assess the degree to which army forces were being prepared to adapt their warfighting skills to conduct multinational peacekeeping missions. Barriers to adaptability were identified in their approach to deployment training and the organization of the military headquarters. U.S. forces were not trained to work with multinational partners and multinational staff members were not integrated into staff planning processes. Methods to improve team adaptability and a framework for considering the relationship among cultural, social cognitive processes and multinational teamwork are proposed.
What do Cultural Dimensions Reveal about Flight Deck Operations BIBAFull-Text 230-234
  Randall J. Mumaw; Barbara E. Holder
Boeing supplies airplanes and provides service and training to customers throughout the world. We want to understand "culture" because of the perception that cultural differences affect the safety of airplane operations. The predominant approach to cultural differences has been characterized by Hutchins, Holder, and Perez (2002) as essentialism. Essentialism is the view that culture is an essential part of every person. It asserts that culture is written indelibly into the identity of a person early in life and makes itself visible in his or her behavior. This view stems from Hofstede's (1980) work and is seen in more recent work on cultural differences that seek out national traits. As an alternative framework, Hutchins et al. propose a contextualist view, which directs attention to how people draw on the resources around them to construct meaningful courses of action. We discuss the differences between these two frameworks in understanding cultural differences.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Processes [Lecture]

Mental Workload and the Display of Abstraction Hierarchy Information BIBAFull-Text 235-239
  Catherine M. Burns; Laura K. Thompson; Antonio Rodriguez
In designing large ecological displays, designers are faced with the question of how to display multiple levels of abstract information. Previous research has shown that people may perform better, in terms of diagnosis speed and accuracy, if multiple levels of information are presented in an integrated format (Burns, 2000). We repeated the study of Burns (2000) which looks at providing abstract information in three formats -- one level at a time, windowed and integrated. We collected eye tracking data at intervals throughout the experiment. Our eye-tracker was able to collect pupil diameter measures and changes. Results showed no notable difference in pupil diameter measures between the integrated condition and the one level at a time condition, but notably higher increases in pupil diameter when abstract information was in separate windows. Furthermore, pupil diameters increased over time in the windowed condition, suggesting that workload with this display may have been increasing. These preliminary data suggest that separating levels of abstract information may increase the mental workload of operators.
Is a Picture Worth a Thousand Words Investigating Structural Knowledge with Textual and Pictorial Stimuli BIBAFull-Text 240-244
  A. William Evans; Raegan M. Hoeft; Florian G. Jentsch; Clint A. Bowers
The differences between the processing of textual and pictorial information have been a topic of research for some time now. Previous research concerning the modality of information has often concentrated on the speed of processing rather than the organizational differences that may exist. This experiment utilized card sorting to evaluate the changes in knowledge organization that occur when information is presented in text and picture formats. In addition to this, the structure of the elicitation task was manipulated to evaluate its effects on sharedness. It was found that textual stimuli produced a greater sharedness among participants in a free sorting task. However, for a structured sorting task, results reversed, and pictorial stimuli created a greater level of sharedness. Overall, structured sorting tasks produced a greater level of sharedness than the free sorting condition, regardless of modality.
Window of Opportunity: Using the Interruption Lag to Manage Disruption in Complex Tasks BIBAFull-Text 245-249
  Sheryl L. Miller
Interruption is a fundamental human problem. Past research has focused on how people resume an interrupted task after attending to some unrelated secondary task, ignoring interruptions that are an integral part of overall performance. In many settings, such as air traffic control or invehicle navigation, people must integrate the processing of the interruption itself and the resumption of the interrupted task. An experiment was conducted to investigate how people manage interruptions in a team decision-making task where interruptions are an integral part of overall performance. One strategy proposed for managing interruptions is the "rehearsal strategy." It was expected that people who rehearsed where they would resume the task would be able to overcome the disruption imposed by interruption. The results indicate that people instructed to use this strategy behaved differently than those who were not instructed. However, instruction did not improve performance on interrupted tasks and may even have been detrimental.
Model-Based Predictions of Interrupted Checklists BIBAFull-Text 250-254
  Melanie Diez; Deborah A. Boehm-Davis; Robert W. Holt
The improper completion of a cockpit checklist has contributed to a number of aviation accidents. In many of these cases, it can be shown that interruptions were a contributing factor in the failure to complete the checklist properly. Unfortunately, most studies of interruptions have provided only post-hoc explanations for these failures. Further, research has focused on whether or not tasks are resumed rather than on predictions of where people will resume a task after an interruption. This paper describes several generic models that were used to explore cognitive strategies for handling interruptions. One of these models was then modified to fit the specific real-world task of completing an aircraft checklist. This model produced detailed a priori predictions about where the interrupted checklist will be resumed. The implications of these predictions for task design and for the use of cognitive modeling as an approach to understanding interruptions are discussed.
The Role Of Attention in Vestibular Processing BIBAFull-Text 255-259
  Michael E. Talkowski; Mark S. Redfern; J. Richard Jennings; Joseph M. Furman
This study investigated the hypothesis that vestibular processing is facilitated by attention, and that suppression of the vestibulo-ocular reflex will lead to dual-task interference in a secondary information processing task. Twelve patients with surgically confirmed absent unilateral vestibular function and twelve healthy age-matched controls participated in this study. All subjects underwent vestibular stimulation through two different types of rotational conditions, one a semicircular canal stimulus and the other an otolith stimulus, two different visual conditions (darkness and fixation of a laser point) and pursuit tracking of a moving laser point. Subjects also performed one of three different secondary information processing tasks (IPT) while undergoing the vestibular condition. The results of this study showed that dual-task interference occurs during vestibular stimulation in both patients and healthy controls, and this interference was more pronounced in patients during more complex IPTs. The results also found no overall difference in performance of a secondary cognitive task when subjects suppressed the vestibulo-ocular reflex by fixating during rotation. These results may suggest that cognitive processing is a necessary component for integration of vestibular information, and this requirement may be greater in patients with unilateral vestibular loss.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Engineering and Design [Lecture]

The Remote Perception Problem BIBAFull-Text 260-264
  James S. Tittle; Axel Roesler; David D. Woods
Previous research (e.g., Casper, 2002; Darken, Kempster, & Peterson, 2001) has shown that observers demonstrate poor spatial awareness based on video provided from remote environments. Such a result is understandable given that remote vision systems provide impoverished representations that leave out higher order cues essential to build coherent percepts and models of the world being explored. If tele-presence or remote vision is to be useful in the future, the raw video needs to somehow be augmented to recover what was lost by decoupling the human perceptual processor from the natural environment.
Work Centered Support System Design: Using Frames to Reduce Work Complexity BIBAFull-Text 265-269
  Robert G. Eggleston; Randall D. Whitaker
We have been developing user interface clients as fully integrated support systems. A Work Centered Support System aids work by using direct and indirect, passive and active methods. An important property of WCSS systems is the use of form representations as passive devices to help reduce work complexity while simultaneously aid users in adaptive problem solving. Based on our experience implementing the design of three WCSSs we have distilled a set of three form-based design principles that help insure a work-centered perspective is expressed in the interface and that aid problem solving. These principles connect problem-solving objects with work domain objects at different levels of abstraction, utilize a first-person work ontology, and organize information selection and layout based on problem relationships. This paper describes the principles and uses illustrations from our designs to indicate how they reduce work complexity.
Mental Models and Ecological Interface Design: An Experimental Investigation BIBAFull-Text 270-274
  Olivier St-Cyr; Catherine M. Burns
We studied the impact of Ecological Interface Design (EID) displays on mental models using the DURESS II simulator. To assess mental models we used a card sorting exercise, a network building exercise based on the Abstraction Hierarchy, and a system behavior prediction exercise. Participants in the EID condition performed significantly better on the card sorting and network building exercises, but poorer on the prediction exercise. Our results are mixed, suggesting that EID may improve the understanding of meansend links and yet, not improve the ability to predict system behavior. The relatively limited experience of participants with the interface as well as our selection of knowledge elicitation techniques may have influenced these results. More research is needed to fully evaluate the impact of EID on mental models.
A Study of Ergonomic Measurement Indices in Evaluating Human-Machine Interfaces BIBAFull-Text 275-279
  Y. Lin; W. J. Zhang; L. G. Watson
Measurement and evaluation of a human-machine interface is a difficult yet very important issue. The difficulty lies in that the issue is inherently a very subjective, and the importance is that the evaluation is part of design process for systems development. The purpose of evaluation is to see how an interface affects the operation of a human-machine control system in two aspects: the operator's mental workload and the performance in completing tasks. In this paper primarily the eye behaviors measure is discussed, together with some other measures, for evaluating two interface design frameworks: Ecological Interface Design (EID) and Function Behavior State (FBS). The measures we used cover both the measure for mental workload and the measure for performance. It is observed through the experiment that these measures vary in different degrees of sensitivity to the hypothesis under investigation and are sometimes in conflict. This has given a motivation for a further study on a new issue called 'measure fusion'. This further study is briefly discussed.
Examining a Possible Triangle Effect: Risk Perception, Sensation Seeking and Focused Attention BIBAFull-Text 280-284
  Charneta Samms; Kayenda Johnson
The purpose of this study was to examine the correlation between risk perception, sensation seeking, and focused attention. Participants were given a set of colors and symbols to rate using a nine point Likert-type risk perception rating scale. A measure of sensation seeking and focused attention was administered using the Thrill and Adventure Seeking and Experience Seeking subscales of the Sensation Seeking Scale and the Expanded Tellegan Absorption Scale respectively. Through the analysis of MANOVA results, the colors red, orange and yellow were identified consistently among all groups as colors of higher warning; however blue differed significantly between groups. These findings signify a potential problem if colors other than those in current standards are under consideration for use in warning designs.
Behind the Curtain: The Cognitive Tasks Behind the Visualizations BIBAFull-Text 285-288
  William C. Elm; David D. Woods; Kevin Bennett; Ann Bisantz; Robert Eggleston; Christine Mitchell
This panel includes participants from academia and industry who have each made significant contributions to the design of effective visualizations to support decision making in a variety of domains. Panel members will offer an example of an innovative decision support visualization concept and discuss the underlying cognitive demands it is meant to support as well as any artifacts they used in its development. Both the nature of the visualization itself, and the linkage to the processes 'behind the curtain' will be presented. Panelists will discuss the various techniques used and the pro's and con's of each.
Team Communication Analysis: Exploiting the Wealth BIBAFull-Text 289
  Nancy J. Cooke
The assessment and diagnosis of team performance is critical for remediation through team training and the design of supportive technologies for teams. Outcome measures used to assess team performance (e.g., mission success, number of targets photographed, time to complete mission) provide minimal diagnostic information. For example, does the team consistently miss targets because of coordination deficits, faulty leadership, or poor situation awareness? Without explanations for effective or ineffective team performance, the target of remediation is unclear.
Using Communication Data to Assess Organizational and System Effectiveness in Future Combat Systems BIBAFull-Text 290-294
  Michael J. Paley; Michael P. Linegang; Rebecca M. Morley
The interconnected nature of the Army's Future Combat System provides an opportunity to use communication analysis as a viable evaluation method of both organizational efficiency and system design. In the current investigation, communications during team-in-the-loop experimentation were collected and analyzed for both content and flow patterns. Results suggest that players did not fully utilize the functionality of a common operating picture (COP) and new technology insertion did not achieve the desired effect within the organization. Requests for information and updates were frequently related to information that could have been found on the COP. The communication patterns suggested that the experimental organization was very much hierarchical, with little horizontal communications. That is, despite the influx of new systems, traditional operations were employed. In this study, communication data were successfully employed to assess operational effectiveness and the quality of system design.
Using Communications Analysis to Understand Team Development: An Example BIBAFull-Text 295-297
  Clint A. Bowers; Florian Jentsch
Team communication and coordination are thought to be key elements in understanding team performance. Almost every major theory and training program emphasizes these factors in attempting to improve team performance. However, the scientific literature regarding effective communication is actually quite sparse. In this paper, we discuss how the precision of analyzing communication frequency data might be improved by analyzing communication patterns. We conclude with an example from a recent study of communications to describe the development of newly-formed teams.
Some Promising Results of Communication-Based Automatic Measures of Team Cognition BIBAFull-Text 298-302
  Preston A. Kiekel; Nancy J. Cooke; Peter W. Foltz; Jamie C. Gorman; Melanie J. Martin
Some have argued that the most appropriate measure of team cognition is a holistic measure directed at the entire team. In particular, communication data are useful for measuring team cognition because of the holistic nature of the data, and because of the connection between communication and declarative cognition. In order to circumvent the logistic difficulties of communication data, the present paper proposes several relatively automatic methods of analysis. Four data types are identified, with low-level physical data vs. content data being one dimension, and sequential vs. static data being the other. Methods addressing all four of these data types are proposed, with the exception of static physical data. Latent Semantic Analysis is an automatic method used to assess content, either statically or sequentially. PRONET is useful to address either physical or content-based sequential data, and we propose CHUMS to address sequential physical data. The usefulness of each method to predict team performance data is assessed.

COGNITIVE ENGINEERING AND DECISION MAKING: Human and Machine Decision Making [Lecture]

Once More With Feeling: Augmenting Recognition Primed Decision Making With Affective Factors BIBAFull-Text 303-307
  Eva Hudlicka; Jonathan Pfautz
Although quintessentially human, emotions have, until recently, been largely ignored in the human factors cognitive engineering / decision-making area. This is surprising, as extensive empirical evidence indicates that emotions, and personality traits, influence human perception and decision-making. This is particularly the case in crisis situations, when extreme affective states may arise (e.g., anxiety). The development of more complete and realistic theories of human perception and decision-making, and associated computational models, will require the inclusion of personality and affective considerations. In this paper, we propose an augmented version of the recognition-primed decision-making theory, which takes into consideration trait and state effects on decision-making. We describe a cognitive architecture that implements this theory, and a generic methodology for modeling trait and state effects within this architecture. Following an initial prototype demonstration, the full architecture is currently being implemented in the context of a military peacekeeping scenario.
Task Demands and Responses to Warnings BIBAFull-Text 308-312
  Joachim Meyer
The study addresses the question how the effort required to obtain task relevant information and the diagnostic value of a warning system affect responses to warnings in a signal detection task that is aided by a binary warning system. In a simulated production task participants had to decide whether to produce or not, based on the length of a rectangle that represented the temperature of raw material and on the output of a binary warning system. The experimental conditions differed in the contrast of the rectangle from the background and in the diagnostic value of the warning. Results showed non-optimal weighting of the warning information. Also, compliance with the warning was stronger when the additional information was more difficult to observe. The results demonstrate that task characteristics have intricate effects on the responses to warnings.
A Field Study of Emergency Ambulance Dispatching: Implications for Decision Support BIBAFull-Text 313-317
  Renee Chow; Kim J. Vicente
To inform the design of computer-based support for decision making, a field study was conducted in a communication centre for emergency medical services (EMS). 142 hours of direct observations, spanning 13 different shifts were conducted. EMS is an intentional work domain that emphasizes human-human interaction over human-machine interaction. This study focused on the information requirements for EMS dispatching, the collaboration between EMS personnel within and beyond the communication centre, and the information that is currently available to the dispatchers. An abstraction-decomposition space (Rasmussen, 1985; Vicente, 1999) was used to model the information requirements in this work domain, and to identify opportunities for enhancing and/or redesigning the decision support.
Supervisory Decision-Making in SemiAutonomous Systems BIBAFull-Text 318-322
  Dwight P. Miller; Jack Schryver; Daniel R. Tufano
Supervisory Decision-Making (SDM) refers to human supervision of several semi-autonomous (non-human) systems in a collaborative manner to accomplish a goal. This study defined SDM and distinguished it from traditional supervisory control and decision-making. An examination of diverse literature in organization design, biology, robotics, innovation diffusion, and trust in automation, yielded no directly applicable or comprehensive models. Field observations were made of large-scale war-games, where operators interacted with semi/autonomous sensors and defense-management systems. Four cognitive models were subsequently developed describing 1) adaptive partnering with automation, 2) technology adoption, 3) trust in automation, and 4) dealing with advice from decision aids. The latter quantitatively models individual, dynamic decisions to accept or reject recommendations made by automated battlespace advisors. The anticipated benefits of this work include more effective human-robot coordination, communication, the identification of experiments, and ultimately design guidelines for robotics, intelligent software agents, intelligent transportation systems, and space exploration.
A Graph Theoretic Model of Human Cognition in Chess BIBAFull-Text 323-326
  Catherine M. Burns; Marko Dodig
Although advances in computing power have greatly improved computer chess playing, human chess players still rival their computer counter-parts. Computer algorithms typically use a strategy of exhaustive search, which is unlikely to be used by human players. We hypothesized that human chess players recognize higher order properties of the game and use these properties to limit their need for exhaustive move searching. We used graph theoretic modeling to quantitatively determine three possible higher order properties. We then conducted an experiment by using the higher order properties to preselect moves for a typical exhaustive search chess engine. We played the enhanced chess engine against its unenhanced version in six games. The enhanced version won all six games, regardless of color played, suggesting that pre-selection of moves based on higher order properties of the game is indeed a viable strategy.

COGNITIVE ENGINEERING AND DECISION MAKING: Automation [Lecture]

Effects of Information and Decision Automation on Multi-Task Performance BIBAFull-Text 327-331
  Ericka Rovira; Marla Zinni; Raja Parasuraman
Automation purported to assist human operators may itself be an additional source of complexity and uncertainty. Because high reliability cannot always be assured, imperfect automation can add to uncertainty and thereby degrade performance. The present study examined the relative benefits and costs of information and decision automation and investigated the effects of uncertainty resulting from automation unreliability during multiple task performance. Subjects were either provided with status information ("information" automation) or a recommendation for action ("decision" automation) for the system monitoring sub-task of the Multi-Attribute Task Battery (MAT). Two levels of automation reliability were compared. The detrimental effect of unreliable automation -- a decrease in the detection rate of malfunctions -- was greater for automation of higher reliability, a result consistent with previous findings of automation-related complacency. This effect of automation unreliability was also greater for decision than for information automation.
Making Unreliable Automation Useful BIBAFull-Text 332-336
  Mark St. John; Daniel I. Manes
Unreliable automation may be usefully applied to situation assessment tasks, but it requires careful analysis of task demands and good interface design. Here we analytically and empirically investigated the case of target detection in which more and less reliable automation identified promising search locations to guide users' attention. Participants searched a field of 44 locations to find four targets. Automation more or less reliably marked some locations as more promising than others. Participants could use even the less reliable automation to direct and facilitated their search compared with manual undirected search. A richer automated marking scheme proved useful but required a more complex search strategy that sometimes hindered participants.
Experimental Study of Automation to Support Time-Critical Replanning Decisions BIBAFull-Text 337-341
  Kip E. Johnson; James K. Kuchar; Charles M. Oman
An experimental study was performed to evaluate several types of automation for time-pressured replanning tasks. Subjects modified a two-dimensional route using waypoint manipulation on a computer screen in response to a sudden change in the displayed environment while having access to one of four types of automation. In addition to a baseline case without automation, subjects received automated assistance that either reduced hazard exposure, ensured meeting time-to-target and fuel constraints, or combined hazard avoidance with time and fuel constraints. Time pressure was imposed by requiring the route to be replanned within four different time limits of less than one minute. Results show that the benefit of automation decreased as time pressure was relaxed. Subjects showed reticence to deviate from highly automated route suggestions even when significant improvements were still possible. In addition, partial automation induced more errors than in cases with no automation, highlighting the potential negative effects of introducing automation.
Comparison of Performance Effects of Adaptive Automation Applied to Various Stages of Human-Machine System Information Processing BIBAFull-Text 342-346
  Michael P. Clamann; Melanie C. Wright; David B. Kaber
Limitations in automation (expert system) capabilities and negative human performance consequences of automation in complex systems have led to the contention that use of computer assistance in high-level human-machine system information processing may be inappropriate. Adaptive automation (AA) has been explored as a solution to these problems; however, research has focused on the performance effects of dynamic control allocations of early sensory and information acquisition functions between human operators and computer controllers of complex systems. It has examined to a limited extent the human performance and workload effects of AA of cognitive tasks, such as decision-making, or of psychomotor functions such as response execution. This research compared the affects of AA applied to psychomotor tasks and cognitive tasks, including information monitoring, information analysis, decision-making, and action implementation, on overall human-machine system performance. Results demonstrated that operators are better able to adapt to AA when applied to lower level functions, such as information acquisition and action implementation, as compared to AA of information analysis and decision making tasks. The results also provided support for the use of AA, as compared to completely manual control.

COGNITIVE ENGINEERING AND DECISION MAKING: Methods in Cognitive Engineering and Decision Making [Lecture]

Model-Based Assessment of Situation Awareness BIBAFull-Text 347-351
  Floyd Glenn; Jennifer McNamara; Jim Hicinbothom; Derek Wischusen
In order to evaluate situation awareness (SA) in a Navy shipboard command and control environment, a model-based framework is being developed based on the foundation of an established technique. An executable cognitive model is used to generate interruption points and probe questions by executing in realtime in parallel with the evaluated individual. The model identifies when critical events occur (or could occur) and also determines what information is critical to identifying these situations and making required decisions. The model instigates interruptions of performance in the simulation environment and presents appropriate probe questions. An empirical exercise was undertaken in order to provide data on the design of this SA assessment instrument for the target command and control application. Subject matter experts (SMEs) were employed to identify critical events and information in simulation scenarios and those specifications were used to provide guidance for the development of the model-based SA assessment technique.
A Field Test of Two Methods for Assessing Infantry Situation Awareness BIBAFull-Text 352-356
  Michael D. Matthews; Scott A. Beal
Two methods for assessing situation awareness (SA) were field tested during infantry exercises. Eight platoons of U.S. Military Academy cadets executed an infantry mission during summer field training exercises. A subjective SA measure, the Mission Awareness Rating Scale (MARS), was given to each platoon leader and one squad leader from each platoon to self-assess both SA and cognitive workload demanded by the tasks. In addition, infantry expert observers rated each platoon and squad leader using the Situation Awareness Behaviorally Anchored Rating Scale (SABARS). Both MARS and SABARS had been validated previously in missions conducted in a virtual environment. In the current field test, both instruments showed evidence of successfully measuring SA. Both instruments show promise for assessing SA in the field, or in other venues where more obtrusive measurement protocols are undesirable.
Scenario Development for Decision Support System Evaluation BIBAFull-Text 357-361
  Emilie M. Roth; James W. Gualtieri; William C. Elm; Scott S. Potter
This paper introduces a methodology for developing scenarios representative of the cognitive and collaborative challenges inherent in a domain of practice for evaluating Decision Support Systems (DSS). Explicit links are made between particular aspects of the DSS and specific cognitive and collaborative demands they are intended to support. The effectiveness of the DSS in supporting performance can then be systematically probed by creating scenarios that are informed by an understanding of individual and team cognitive processing factors, fundamental relationships within the domain, and known complicating factors that can arise in the domain to challenge cognitive and collaborative performance. This paper introduces a set of explicit artifacts to systematically create such scenarios to provide feedback on the viability of the DSS design concepts (e.g., are the hypothesized positive impacts of the DSS realized?), as well as feedback on additional unanticipated requirements for support.
Human-Automated Judgment Learning: A Methodology to Investigate Human Interaction With Automated Judges BIBAFull-Text 362-366
  Ellen J. Bass; Amy R. Pritchett
Human-automated Judgment Learning (HAJL) is a methodology for investigating human-automated judgment system interaction capturing the judgment processes of the human and automated judge, features of the task environment, and relationships between them. HAJL provides measures for conflict between the judges, compromise by the human judge, adaptation of the human judge to the automated one, and for assessing how well the human judge understands the automated one. HAJL was empirically tested using a simplified air traffic conflict prediction task. Two between-subjects manipulations were crossed to investigate HAJL's sensitivity to training and design interventions. Statistically significant differences were found with respect to 1) males outperforming females judgment performance before feedback from the automated judge was available while the judge's subsequent output eliminated this difference; 2) participants tended to compromise with the automated judge over time. HAJL also identified a trend for participants with higher judgment achievement to predict better the automated judgment and thought that their own judgments were closer to the automated judge than they were.
Design and Evaluation of Usable Systems BIBAFull-Text 367-371
  John F. McGrew
This paper discusses a case study of a design and evaluation of a change management system at a large Telecommunications Corporation. The design and evaluation were done using the facilitated genetic algorithm (a parallel design method) and user decision style analysis. During the facilitated genetic algorithm the design team followed the procedure of the genetic algorithm. Usability was evaluated by applying user decision style analysis to the designed system. The design is compared with an existing system and with one designed by an analyst. The change management system designed by the facilitated genetic algorithm took less time to design and decision style analysis indicated it would be easier to use than the other two systems.

COGNITIVE ENGINEERING AND DECISION MAKING: Aviation and Cognitive Engineering [Lecture]

Modeling Error Recovery in Dynamic Collaborative Domains BIBAFull-Text 372-376
  Mark I. Nikolic; Nadine B. Sarter
For many years, the focus of research in the area of human error was the prevention of erroneous actions and assessments through training and design. However, errors can never be eliminated completely. Therefore, the goal of more recent efforts is to minimize their negative consequences through support for error management, i.e., the detection, explanation, and recovery from erroneous actions. For the most part, these efforts have examined the first step in this sequence -- error detection. In contrast, little is known about how operators explain and recover from errors. This is true especially for dynamic collaborative environments such as aviation. In this paper, we present findings from a survey and an incident report analysis that suggest the need for adapting the current model of error recovery. Specifically, we emphasize the importance of considering constraints imposed by specific domains in order to predict and explain the predominance and success of certain recovery strategies.
Mental Models, Situation Models, and Expertise in Flight Situation Awareness BIBAFull-Text 377-381
  Mark T. Jodlowski; Stephanie M. Doane; Young Woo Sohn
The present research examines cognitive processes that support flight situation awareness (SA). Of particular interest is pilot access to condition-action rules that reflect their mental models of flight, and their ability to determine when the rules apply in the context of a specific situation. Pilots were asked to reason about events that take place during flight in multiple 3-screen computer-based trials. In each trial, the first screen indicated a control movement, the second screen depicted a meaningful flight situation, and the third screen indicated a flight situation change. Pilots were asked to judge whether the change depicted in the third screen was consistent with what was expected following application of the control movement depicted in the first screen to the flight situation depicted in the second screen. Judgment accuracy suggests superior access to mental models versus situation models, and systematic differences in knowledge organization as a function of piloting expertise.
Impact of Contextual Information on Automation Brittleness BIBAFull-Text 382-386
  Jennifer J. Ockerman; Amy R. Pritchett
Brittleness, the inability to provide accurate assistance in all situations, is frequently an issue with complex automation and automatic decision aids. This paper examines a method of mitigating the impact of brittleness on overall system function. Using the task of planning an emergency descent for a commercial aircraft, this study found that the presence of contextual information in the presentation of an automatically generated emergency descent procedure might aid in mitigating the effects of automation brittleness. By providing pilots with rationale as to the design of the descent procedure, the pilots were better able to correctly determine why a provided procedure was or was not feasible.
Using Cognitive Theory to Enhance Aviation Security X-Ray Screening BIBAFull-Text 387-391
  R. L. Maguire; A. J. McClumpha; K. B. Tatlock
A fundamental part of the aviation security process is 'baggage screening'. Aviation security screeners are required to search for threat items within an X-ray image. The task is complex, demanding, involves perceptual and cognitive components and is vital to ensure the safety of the travelling public. QinetiQ CHS has undertaken a research programme, sponsored by Transport Security Division of the UK Department for Transport, to investigate the nature of screener expertise and to develop technologies that will support this expertise. This paper outlines recent findings and discusses support technologies that have been produced as a consequence of this research.
Interference Effects on the Recall of Words Heard and Read: Considerations for ATC Communication BIBAFull-Text 392-396
  Matthew R. Risser; Danielle S. McNamara; Carryl L. Baldwin; Mark W. Scerbo; Immanuel Barshi
Two experiments were conducted to investigate the effects of interference on memory for words that were either read or heard. Interference tasks required either visual, verbal, or central executive (CE) working memory resources. Experiment I examined effects of simultaneous interference, whereas Experiment 2 examined the effects of posttask (subsequent) interference. When interference occurred simultaneously with word presentation, the verbal and CE interference tasks were most disruptive, regardless of whether the words were read or heard. Furthermore, hearing words facilitated recall in comparison to reading words regardless of interference source. When the interference task followed word presentation, CE interference again was the most disruptive. However, the effects of the visual and verbal interference tasks were equivalent. These results are discussed with respect to communication mode in ATC messages to pilots (i.e., textual data-link messages vs. voice transmissions).
Team Cognition: Process and Performance at the inter- and Intra-Individual Level BIBAFull-Text 397
  Eduardo Salas; Stephen M. Fiore
Because of the prevalence of teams in organizations today, many are formed without much forethought, along with the expectation that only gains in productivity can result. Although there are substantial benefits associated with teamwork (e.g., Cannon-Bowers & Salas, 1998), the reality is that there is little guarantee of success, as many teams fail for any number of reasons (e.g., Hackman, 1998). Thus, given this reliance on teams, it behooves researchers to gain a full understanding of teamwork by delineating the factors that impact team effectiveness.
Distributed Teams and Distributed Memory BIBAFull-Text 398-402
  Stephen M. Fiore; Haydee M. Cuevas; Eduardo Salas; Jonathan W. Schooler
The nature of teams is changing in that the implementation of distributed teams as a definable organizational unit has substantially increased. In this paper we discuss a portion of the cognitive processes potentially impacting distributed team performance. We elaborate on how team opacity arising from distributed interaction can impact team cognition, with an emphasis on the critical memory components that are foundational to the development and implementation of shared mental models.
Addressing Limitations of the Measurement of Team Cognition BIBAFull-Text 403-407
  Nancy Cooke; Preston A. Kiekel; Brian Bell; Eduardo Salas
Team cognition is more than the sum of the cognition of the individual team members. Instead, it emerges from the interplay of individual cognition and team process behaviors. Team cognition has been implicated as a major factor underlying team performance and thus, its measurement is critical for team training and design. Measures of team cognition, however, are limited in a number of ways. For instance, measures are taken at an individual level and aggregated, rather than pursuing data collection at the more holistic level of the team. Further, measures do not capture the heterogeneous knowledge backgrounds of team members. We have begun to address these and other limitations by developing new measures and applying them in four studies of team performance in military synthetic task environments. We highlight the results of these studies, which support the validity of our measures of taskwork knowledge, teamwork knowledge, and team situation awareness.
From Team Structure to Team Performance: A Framework BIBAFull-Text 408-412
  Jean MacMillan; Elliot E. Entin; Daniel Serfaty
This paper presents a theoretical framework that links the organizational structure of a team to the team's performance through intervening factors such as the need for coordination, the need for communication, the extent to which the team's mission can be pre-planned, and the team's mutual awareness of each other's tasks. We suggest that the organizational structure of a team interacts with the nature of the team's mission (in particular, the interdependence among the tasks to be performed) to generate the need for coordination in order to successfully accomplish the mission. The need for coordination and the extent to which the mission can be pre-planned drive the need for communication during the mission. The efficiency of that communication is, in turn, affected by factors such as the team's level of mutual awareness. The paper presents several innovative measures for components of the suggested framework, and summarizes empirical evidence for the framework.
Integrating Agents into Human Teams BIBAFull-Text 413-417
  Katia Sycara; Michael Lewis
Software agents represent a radical departure from earlier monolithic approaches to artificial intelligence by introducing intelligence in small packages in many different places. For each instance of potential aiding there are two questions: 1- can a software agent perform the task? and 2- can the agent's assistance contribute to team performance? Our research addresses these two issues by demonstrating the feasibility of sophisticated agent assistance in scenario-based technology demonstrations and investigating the contribution of agent assistance to human team performance using simplified, controllable laboratory experiments.

COGNITIVE ENGINEERING AND DECISION MAKING: Decision Aids and Trust [Lecture]

Measurement of Human Trust in a Hybrid Inspection for Varying Error Patterns BIBAFull-Text 418-422
  Kartik Madhani; Mohammad T. Khasawneh; Sittichai Kaewkuekool; Anand K. Gramopadhye; Brian J. Melloy
The emphasis of this research was on the effect of human trust in a hybrid inspection system with varying error patterns. Experiments were conducted using a hybrid inspection task involving four common types of error patterns, and subjects were requested to rate their trust in the system at different stages. Results showed that subjects' ratings of trust were based on how they perceived the behavior of the computer. However, this rating was not sensitive to the type of error pattern. A significant change in trust was found in all the systems considered for the study. In addition, the results reflect that there was a significant decrease in trust when subjects inspected the assigned experimental system after inspecting the perfect one. Finally, the components of trust that fit into the trust model at each stage of a particular system were determined using the stepwise regression model.
Judgment and Trust in Conjunction With Automated Decision Aids: A Theoretical Model and Empirical Investigation BIBAFull-Text 423-427
  Younho Seong; Ann M. Bisantz
The importance of understanding and supporting human operators' judgment and decision-making has been recognized in a variety of contexts. Of interest in these systems is the extent to which operators utilize and trust such systems, particularly where operators do not have any means to access the environment directly. Operators' trust in automated decision aids is the critical component affecting their performance in estimating the environmental states. A model of human operators' judgment with automated decision aids was developed using the Lens Model framework. This model shows not only different characteristics of automated decision aids, but also the representation of operators' judgment policy. An empirical investigation on operators' judgment performance and trust in conjunction with automated decision aids is described in this research. Among the potential characteristics of such systems that may affect operators' judgment performance and trust, three aspects were controlled. Results provide strong support for factors in the theoretical framework and for identification of the types of information to increase the level of operators' understanding.
Effects of Unreliable Automation on Decision Making in Command and Control BIBAFull-Text 428-432
  Ericka Rovira; Kathleen McGarry; Raja Parasuraman
The effectiveness of automated decision aids used by human operators in command and control systems may depend not only on automation reliability, but also on the type (stage) and level the automated support provides. Automation can be applied to information acquisition, information integration and analysis, decision choice selection, or action implementation (Parasuraman, Sheridan, & Wickens, 2000). The present study examined the effects of variations in the stage of automation support on performance in a "Sensor to Shooter" targeting simulation of command and control. Independent variables included the type and level of automation support (complete listing, priority listing, top choices, and recommendation of decision choice) and the reliability of the automation (60% and 80%). Dependent variables included accuracy and reaction time of target engagement decisions. Compared to manual performance, reliable automation did not affect the accuracy of target engagement decisions but did significantly reduce decision times. When the automation was unreliable, under the higher reliability condition (80%) there was a greater cost in accuracy performance for higher levels of automation aiding (priority listing, top choice, and recommendation) than at a lower level (complete listing). The results support the view that automation unreliability has a greater performance cost for decision automation than for information automation. This performance cost generalizes across a number of different forms of decision-aiding.

COGNITIVE ENGINEERING AND DECISION MAKING: Articles

Using Software Agents in a Work Centered Support System for Weather Forecasting and Monitoring BIBAFull-Text 433-437
  Ron Scott; Emilie M. Roth; Stephen E. Deutsch; Erika Malchiodi; Tom Kazmierczak; Robert G. Eggleston; Samuel R. Kuper; Randall Whitaker
There has been a growing interest in developing system architectures and human-software agent interaction paradigms that deploy software agents in the service of effective support for human task performance. This paper describes an agent-based system for a weather forecasting and monitoring application, called Work Centered Support System for Global Weather Management (WCSS-GWM), that takes this approach. WCSS-GWM exemplifies and extends Cognitive Engineering (CE) principles for effecting human-software agent interaction and Work Centered Support System (WCSS) concepts. Two fundamental CE principles are observability and directability. Users need to be able to 'see' what the software agents are doing and be able to re-direct the software agents as task demands change. The WCSS brings an additional, complementary perspective, emphasizing the need to support the multiple facets involved in individual cognitive and collaborative work (decision-making, product development, collaboration, and work management). The WCSS-GWM agent-based architecture is explicitly designed with these objectives in mind.

COGNITIVE ENGINEERING AND DECISION MAKING: Decision Aids and Trust [Lecture]

Effects of Information Automation and Decision-Aiding Cueing on Action Implementation in a Visual Search Task BIBAFull-Text 438-442
  Scott M. Galster; Robert S. Bolia; Raja Parasuraman
A visual search paradigm was used to examine the effects of status information as well as decision-aiding automation in a target detection and processing task. Manual, information automation, and decision-aiding automation conditions were manipulated with the size of the distractor set. Participants were required to respond to the presence or absence of a target in a time-limited trial. In the information automation condition, status information regarding target presence was presented to the participant. The participants were informed that the information automation was not perfectly reliable. A significant detection performance improvement was observed in the information automation condition. This improvement was more marked in the conditions with the higher number of distractors. Additionally, response times were improved when the information automation cue was present. Effects of cue validity and incorrect responses are presented. Implications of the results and future studies are discussed.

COGNITIVE ENGINEERING AND DECISION MAKING: Decision Making in the Armed Forces [Lecture]

Constructing Battlefield Understanding: A Comparison of Experienced and Novice Decision Makers in Different Contexts BIBAFull-Text 443-447
  Lawrence G. Shattuck; Christopher Talcott; Michael D. Matthews; Jennifer Clark; Matthew Swiergosz
Understanding the evolving, complex events on a battlefield requires a decision maker to gather and integrate data from disparate sources. The work described herein is the final in a series of studies that investigates the decision making processes employed by military decision makers. Twenty-one Army officers participated in a simulation of an offensive military operation. The results of this study are compared to the results of three previous studies involving participants with differing levels of expertise (experienced versus novice) and using different types of scenarios (defense versus offense). Results strongly suggest that performance of military decision makers varies based on levels of experience and the data they gather vary according to context. Implications for design of decision support systems are also discussed.
Improving Tactical Decision Making through Critical Thinking BIBAFull-Text 448-452
  Karel van den Bosch; Anne S. Helsdingen
Expert military commanders construct an initial but comprehensive interpretation of complex or unfamiliar tactical situations (story). They subsequently adjust and refine this story by evaluating available information, by searching for consistency, and by critically testing underlying assumptions. This approach is used to develop critical thinking training. Two effect studies were conducted. Individual commanders (study 1) and commanding teams (study 2) played scenario-based exercises in both simplified and high-fidelity task environments. Half the group received instruction, guidance, and feedback in critical thinking. The other half received the same scenarios, but without any support. After training, test scenarios were administered to both groups. Results showed positive effects on the process of tactical command (i.e. better argumentation for situation assessment) as well as on the outcomes (i.e. more and better contingency plans). The method supports not only individual commanders, it also helps teams to develop a common understanding of the situation and to co-ordinate team actions.
Assessment of the TADMUS DSS with Work Domain Analysis BIBAFull-Text 453-457
  Catherine M. Burns; David Bryant; Bruce Chalmers
We applied Work Domain Analysis (WDA) to the evaluation of a military decision support system (DSS) developed as part of the Tactical Decision Making Under Stress (TADMUS) project. The purpose of the evaluation was to assess the degree of fit of the TADMUS DSS, designed for a U.S. naval environment, to the command and control of the Canadian Navy's HALIFAX Class frigate, a different environment. Using work domain models developed for the HALIFAX Class ship, we compared the TADMUS DSS against these models using Functional Information Profiles. Results of the analysis are discussed, as well as the appropriateness of using WDA as a tool in the system evaluation process.
Experimental Design Interrogation of Network Simulation Models of U.S. Army Command and Control Centers BIBAFull-Text 458-462
  Sam E. Middlebrooks; Robert C. Williges
Using a task network computer simulation previously developed by the U.S. Army to investigate workload conditions in a command and control center, this project developed new methodologies to use computer simulations to predict conditions for optimal human performance. By using an experimental design to interrogate the model to see what the decision makers in the work team deemed to be important, predictions were made about how the work domain could be optimized for the most efficient human performance. An augmented fractional-factorial design was developed that allowed an analysis of the main effect for each independent variable along with predictions of higher order components that might exist in each main effect. A major study finding was the extent to which battalion commanders focused their attention on establishing and maintaining situational awareness during combat operations and the need to present information to the commander in a way that supported rather than detracted from situation understanding.
Power Tool for Countering Cyberwar: Visualizations for Information Assurance and Computer Network Defense BIBAFull-Text 463-467
  James W. Gualtieri; William C. Elm
There has been a growing need for military decision-makers to maintain the integrity of the information contained within their computer network. Tools to support Information Assurance and Computer Network Defense (IA-CND) are needed to defend their information infrastructure and conduct Computer Network Operations with a new level of insight and understanding. This paper describes one effort to develop visualizations to aid these decision-makers in the highly abstract, complex and dynamic mission of IA-CND. This paper describes the development of a IA-CND Communications Display. Using a Cognitive Systems Engineering methodology, this project transitioned from a broad description of a work domain, to the development of decision aiding concepts for a particular portion of that domain. This methodology also provided a means to develop breakthrough support for a decision difficult domain.
GUTs or No GUTs (Grand Unified Theories): DoesCanShould Cognitive Engineering Have G.U.T.s BIBAFull-Text 468-471
  David D. Woods
What are the GUTs of Cognitive Systems Engineering (CSE)? G.U.T. is an abbreviation for Grand Unified Theory. As Cognitive Science matured, Allen Newell proposed a unifying model of cognition expressed as a software architecture SOAR. Similarly, John Anderson developed ACTR also claiming it represented a unified theory of cognition in the form of a computer simulation. Both of these cognitive architectures are computer programs that claim to simulate or be the basis for creating simulations of how people perform and learn cognitive tasks. Taking the development of Cognitive Science as a possible analogy for the potential development of Cognitive Systems Engineering, this panel discussion provides a platform to stimulate a vigorous exchange of ideas about the foundation of and potential futures of CSE.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Task Analysis and Cognitive Modeling [Lecture]

Using Goal Directed Task Analysis with Army Brigade Officer Teams BIBAFull-Text 472-476
  Cheryl A. Bolstad; Jennifer M. Riley; Debra G. Jones; Mica R. Endsley
A greater understanding of team cognitive processes can be facilitated by identifying the individual goals of the team members and their situation awareness (SA) requirements. In some environments, such as military operations, the shear complexity, size, and composition of the team make this research quite challenging. Using a form of cognitive task analysis, we have developed an approach to address some of these team issues. In this paper we discuss the use of goal directed cognitive task analysis (GDTA) to obtain an accurate depiction of the SA requirements and key goals for several brigade officers. We further discuss how this information is being used to address team issues such as designing systems for enhancing team performance and decision making with Army brigade officers.
Computer-Aided Decision Support: Is it What the Army Needs BIBAFull-Text 477-481
  Jennifer M. Riley; Mica R. Endsley
There has been a call for computer-aided decision support in Army and other military operations as a result of the increasing pace of current and future warfare. These tools are expected to speed up the critical thinking process, for example in battle planning and course of action analysis, by providing users with critical information and off-loading various cognitive tasks. There is a need, however, to determine the kinds of decision tools that are best suited to Army operational needs and to consider the potential implementation issues associated with application of automated tools to complex operations. A structured approach is needed to analyze Army operations and reveal the critical information needs associated with the various positions, and to determine what is appropriate in terms of decision aiding systems. Understanding information needs and adequately designing for human integration with decision tools will be important to successful overall system performance.
An Empirical Comparison of Methods for Eliciting and Modeling Expert Knowledge BIBAFull-Text 482-486
  Robert R. Hoffman; John W. Coffey; Mary Jo Carnot; Joseph D. Novak
The goal of this project in Human-Centered Computing was to apply a variety of methods of Cognitive Task Analysis (CTA) and Cognitive Field Research (CFR) to support a complete process going all the way from knowledge elicitation to leverage point identification and then to system prototyping, and also use this as an opportunity to empirically compare and evaluate the methods. The research relied upon the participation of expert, journeyman, and apprentice weather forecasters at the Naval Training Meteorology and Oceanography Facility at Pensacola Naval Air Station. Methods included Protocol Analysis, a number of types of structured interviews, workspace and work patterns analysis, the Critical Decision Method, the Knowledge Audit, Concept Mapping, and the Cognitive Modeling Procedure. The methods were compared in terms of (1) their yield of information that was useful in modeling expert knowledge, (2) their yield in terms of identification of leverage points (where the application of new technology might bring about positive change), and (3) their efficiency. Efficiency was gauged in terms of total effort (time to prepare to run a procedure, plus time to run the procedure, plus time to analyze the data) relative to the yield (number of leverage points identified, number of propositions suitable for use in a model of domain knowledge). CTA/CFR methods supported the identification of dozens of leverage points and also yielded behaviorally-validated models of the reasoning of expert forecasters. Knowledge modeling using Concept-Mapping resulted in over a thousand propositions covering domain knowledge. The Critical Decision Method yielded a number of richly-populated case studies with associated Decision Requirements Tables. Results speak to the relative efficiency of various methods of CTA/CFR, and also the strengths of each of the methods. In addition to extending our empirical base on the comparison of knowledge elicitation methods, a deliverable from the project was a knowledge model that illustrates human-centered computing in that it integrates training support and performance aiding.
Differential Access Hypothesis: The Effects of Task and Information Type on the Validity of Knowledge Acquisition Methods BIBAFull-Text 487-491
  Deane B. Cheatham; Sharolyn Converse Lane
The types of knowledge captured using three knowledge acquisition (KA) methods, conceptual graphs, backward thinking, and sorting tasks, were examined. One hundred and forty-four participants were assigned to one of four conditions: (a) procedural-spatial, (b) procedural-verbal, (c) declarative-spatial, and (d) declarative-verbal. Participants in procedural conditions learned a virtual environment's layout before performing one of three KA tasks. Participants in declarative conditions received a tutorial about McCune-Albright Syndrome before completing a KA task. The procedural and declarative information was presented either spatially or verbally, depending on the condition. The predictive validity of each KA method for each information type (procedural vs. declarative), task type (i.e., spatial vs. verbal), and combinations of information and task types was evaluated by comparing the accuracy of the knowledge depicted by KA methods to various performance measures. Findings indicated that both task type and information type affect the validity of KA methods for capturing knowledge structures.
Computational Cognitive Models ISO Ecologically Optimal Strategies BIBAFull-Text 492-496
  Wayne D. Gray; Michael J. Schoelles; Christopher W. Myers
Our work with the Argus Prime (Schoelles & Gray, 2001) simulated task environment has uncovered a variety of strategies that subjects use, at least sometimes, during target acquisition. However, it is difficult to determine how well subjects implement these strategies and, if implemented, how much these strategies contribute to overall performance. Recently, we have adopted Byrne and Kirlik's (2002) cognitive-ecological approach to determine what strategies work best in different task environments. In the work reported here, we took one computational cognitive model and, holding all else constant, swapped in and out alternative strategies for target acquisition. We then ran each of these simulated human users ten times through each of four interface conditions.

COGNITIVE ENGINEERING AND DECISION MAKING: Decision Making [Lecture]

Influence of Analytically and Intuitively Framed Instructions upon Multi-Attribute Decision Task Approach BIBAFull-Text 497-500
  Rebecca J. White; Thomas E. Nygren
Individuals may rely upon a number of decision making strategies in their approach to a complex decision making environment. For example, people may have a predisposition to rely upon intuitive and analytical decision making styles during task performance. These decision making styles, as measured by a Decision Making Styles Inventory (DMI), have been found to predict performance on a multi-attribute decision making task. It follows that manipulating the manner in which task instructions are framed, either analytically or intuitively, may have an influence upon task approach and performance as well. Influence of analytic and intuitive instructions for a multi-attribute decision making task are examined in this paper.
Examining Decision-Making Strategies Based on Information Acquisition and Information Search Time BIBAFull-Text 501-505
  Julie L. Marble; Heather D. Medema; Susan G. Hill
Eight participants reviewed a multimedia presentation regarding the hypoxic zone phenomenon in a role-play as a legislator's aide. They rated the phenomenon's importance to the United States and indicated what portion of the legislator's budget to devote to research of it. After viewing a segment of the presentation, participants indicated their distance to a decision and confidence that would be their final decision. Interviews after each segment revealed two decision strategies: slow movement toward a decision, or abrupt decision-making after approximately half the presentation. Decision style was correlated with decision confidence. These two groups differed in their trade-offs of willingness to spend time in information search and need for more information. Slow decision makers were less confident about their final decision; acquisition of information was more critical than time spent on the information search. Abrupt decision-makers were more confident of their final decision; minimizing time spent in information search was more critical than information acquisition.
A Lens Model Analysis of Confidence Judgments: Beyond Calibration Measures BIBAFull-Text 506-510
  Chang S. Nam; Ann M. Bisantz
To better understand the judgment processes leading to an unjustifiably high level of confidence, the present study tested the impact of task characteristics as determinants of overconfidence, using a Lens Model analysis. Participants were asked to make a repair judgment about a pavement crack, and then rate the confidence in their judgments. Two, 2 level between-participants conditions (i.e., high/low environmental predictability and yes/no confidence judgment training), and one 4 level within-participants condition (i.e., task familiarity) were used as independent variables. Lens Model parameters and calibration measures were used as dependent variables. Results showed that similar to results in prior studies, participants tended to be overconfident, in which their level of overconfidence was greater in a less predictable (i.e., more difficult) task environment. These effects were only somewhat mitigated by confidence judgment training, not being affected by increased task familiarity. An analysis of Lens Model parameters indicated that participants who were more overconfident, may have been reflected in their assessments of confidence, their belief that they were making judgments consistently.
Measuring Judgment Interaction with Displays and Automation BIBAFull-Text 511-515
  Amy R. Pritchett; Ann M. Bisantz
Methodologies for assessing human judgment in complex domains are important for design of both displays that inform judgments and automated systems that suggest judgments. This paper applies n-system Lens Model methods for evaluating human judgments, examining the impact of displays, and assessing the similarity between human judgments and the judgment policies used by automated systems. First, the need for and concepts underlying, judgment analysis are outlined. Then the n-system Lens Model and its parameters are formally described. This model is then used to examine a study of aircraft collision detection examined previously using standard ANOVA methods. Our analysis found the same main effects as the earlier analysis. However, the n-system Lens Model analysis provided greater resolution regarding the information relied upon for judgments, the impact of displays on judgment, and the attributes of human judgments that are -- and are not -- similar to judgments produced by automated system.
Utilizing Dynamic Cognitive Feedback to Facilitate Learning on Diagnostic Tasks BIBAFull-Text 516-520
  Gordon J. Gattie; Ann M. Bisantz
As more organizations rely on computer-based training, greater emphasis should be placed on constructive feedback information to improve performance. Providing effective information support for decision tasks such as medical diagnosis is a challenging problem for interface designers. Dynamic cognitive feedback based on the Lens Model was provided for 36 medical experts-intraining and 36 medically untrained participants. Participants examined 50 dental patient case studies consisting of color photographs, demographic information, and feedback information. Task predictability and feedback content were manipulated. Trained participants scored higher and applied their decision policies more consistently. Results also indicated performance differences based on feedback type and participants' experience level. Trained participants relied more on information between the judgment and individual environmental cues, whereas untrained participants performed better with feedback pertaining to their own decision policies.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Work Analysis for Large-Scale Systems: Recurring Issues [Symposium]

Validating Methods in Cognitive Engineering: A Comparison of Two Work Domain Models BIBAFull-Text 521-525
  Ann M. Bisantz; Catherine M. Burns; Emilie Roth
Work domain analysis (WDA) is becoming a popular technique for the analysis of complex systems. WDA is one of the frameworks of Cognitive Work Analysis (CWA; Vicente, 1999) and can be used to gather work domain constraints as part of a user centered design process. In this paper, we discuss issues of inter-modeler reliability with WDA. The authors of this paper performed, over similar time periods, cognitive engineering analyses, including work domain analyses using abstraction hierarchy models, of two similar systems: naval combat vessels. In this paper, we compare these models for similarities and differences. Comparison indicated similarities in model scope and content, which would be an expected result of the application of a reliable modeling technique to two similar systems. Differences between the models included the use of multi-part vs. a single model to represent components of the overall ship-sea-contact system, the related decisions to include sensors explicitly in the model, and the descriptions of abstract functions and constraints included in the two models. Exploration of these differences illuminated methodological as well as theoretical considerations in applying work domain modeling techniques that can provide guidance to other modelers.
Eid and Analytic Redundancy: Reports from the Process BIBAFull-Text 526-530
  Penelope Sanderson; Dal Vernon C. Reising
We outline the relation of the concept of analytic redundancy to Cognitive Work Analysis and to Ecological Interface Design. Analytic redundancy refers to different ways that system inputs can be related to system outputs so as to retain system objectives, whether for inferring state or exercising control. We extend previous treatments on the concept of analytic redundancy and stress the importance of finding a strong representational formalism if a human operator supported by an EID interface is to provide analytic redundancy and be capable of "finishing the design". While increasingly straightforward in the visual domain, there are still challenges in the auditory domain.
Work Centered Design of a Usaf Mission Planning System BIBAFull-Text 531-535
  Gavan Lintern; Diane Miller; Keith Baker
In large-scale socio-technical systems such as military command and control, operators must work with complex and dynamic information from many diverse sources. For this project, we used the Cognitive Work Analysis and Ecological Interface Design frameworks to design a virtual workspace for the USAF work domain of Special Assignment Airlift Mission planning. Based on information made available through the analysis, we developed a workspace prototype in which multiple View-Ports house distinct functional requirements and in which options are made available to link various View-Port functionalities in the mission planning process. In this paper we illustrate how we bridged the gap between analysis and design by developing a link from the analytic products of our Cognitive Work Analysis to the design of the ecological workspace.
Empirical Evaluation of an Industrial Application of Ecological Interface Design BIBAFull-Text 536-540
  Greg A. Jamieson
Abnormal events in production plants cost the petrochemical industry billions of dollars annually. In part, these events are difficult to deal with because current interfaces do not adequately inform operators about the state of the process. Ecological human-machine interfaces aim to provide information about higher-level process functions. Several laboratory simulator studies have shown that, in comparison with contemporary process interfaces, ecological interfaces can lead to faster fault detection, better root-cause diagnosis, and more effective control responses. However, an empirical evaluation of these findings for professional operators in more realistic plant settings has been absent from the literature. In this study, two ecological interfaces were created for a representative petrochemical refining process. One was a traditional ecological interface based on a system-based analysis and the other was an ecological interface augmented with additional task-based information. Professional operators used the novel interfaces in an industrial simulator to monitor for, diagnose, and respond to several types of process events. In comparison to operators using the current process interface, participants in both ecological interface conditions showed better control performance, while the participants using the augmented ecological interface provided more accurate fault diagnoses than either of the other two groups. The results shed light on practical implications for the use of ecological interfaces in the process industries.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Engineering & Decision Making Posters

Policy Capturing and Fuzzy Logic: A Better Approach to Representing Judgment Data BIBAFull-Text 541-545
  Amy E. Bolton; Randolph S. Astwood; Gwendolyn E. Campbell
At the 45th annual meeting of HFES, we conducted an alternative format session in which fuzzy logic was introduced as an alternative approach to analyzing judgment data and representing decision-making policies (see Buff et al., 2001). During the alternative format session, usability judgments were collected on-site for Advanced Distance Learning (ADL) applications. These data provided the basis for an empirical assessment of the value added of one modeling technique, fuzzy logic, over the more traditional approach to analyzing policy capturing data, multiple linear regression. This paper describes the results of an empirical assessment of the two modeling techniques. For a discussion of the empirical results of the impact of the different usability dimensions on the learning effectiveness of ADL applications, see Holness, Pharmer, and Buff (2002).
Crisis Management Teams (CMT): Leveraging the Science of Team Performance Under Stress BIBAFull-Text 546-550
  C. Shawn Burke; Katherine A. Wilson; Eduardo Salas
Crisis management teams play a vital role in our nation's ability to effectively respond to disaster situations. However, the tasks that these teams perform happen infrequently and are often ambiguous and dynamic in nature. Furthermore, they involve interdependent action from many different organizations that may not work together on a regular basis. While it is common to train members in task-work skills, less common is the explicit training of teamwork skills. Research and real-world examples show that teamwork is not an automatic consequence of being in a team. As CMTs are often interdisciplinary and operate in environments characterized by stressors effective teamwork becomes even more of a challenge. Several communities have invested heavily into understanding the impact of stress on teamwork and decision-making within complex environments. The focus of this paper will be extracting lessons from these communities in an effort to provide guidance to CMTs.
The Influence of Feedback on Automation Use, Misuse, and Disuse BIBAFull-Text 551-555
  Mary Dzindolet; Linda Pierce; Scott Peterson; Lori Purcell; Hall Beck
The use of automated decision aids is increasing. Unfortunately, the productivity of human-automated work teams is not always superior to that of the human operator or the computer working alone (Parasuraman & Riley, 1997). In order to examine the effects of various kinds of feedback on appropriate automation use, 159 students provided with an automated aid determined whether a camouflaged soldier was present in 300 slides. A 2 (rationale why aid might err) X 2 (continuous feedback) X 2 (aid's relative performance) X 2 (aid's decision) ANOVA was performed with the transformed p(error) separately for the trials in which the target was present and for those in which the target was absent. Results indicated that participants were able to appropriately rely on the automated aid. For example, those paired with a superior aid were more likely to rely on the aid's decisions than ignore them; those paired with an inferior aid were more likely to ignore the aid than rely on it. A three way interaction indicated that this finding was most strong when participants were provided with information concerning why their aid might err, F(1, 51) = 3.27, p <.08. Implications for future research are discussed.
Distributed Cognition in Shared Information Spaces BIBAFull-Text 556-560
  Elena Theodorou; Michael D. McNeese; Lori Ferzandi; Xun Ge; Tyrone Jefferson
This study examined higher order perception, cognition, and individual-cultural differences as a basis for the rapid use of knowledge in complex problems requiring distributed team members. Previous research suggests that when complex problem-solving teams acquire perceptually anchored knowledge and engage in perceptual contrasts and comparisons, team members may spontaneously access knowledge given similarly situated problems. Our premise is that perceptual anchors may provide the basis for formulating shared mental models, which can be used to assess situations and resolve differences in individual, unique knowledge. However, distributed cognition settings may diminish the development of these models despite the advantages of perceptual anchors. Because distributed cognition often incurs through shared information spaces, this study utilized chatrooms to enact a distributed environment. Initial analyses partially support previous research (McNeese, 2000) that has examined the role of cognitive processes in facilitating knowledge acquisition and transfer. Individual problem solvers show positive transfer but distributed team members do not. Gender and ethnicity may also impact acquisition and transfer results. Results suggest the need for intelligent interfaces/collaborative technologies to improve effectiveness and efficiency in appropriating perceptual differentiation in distributed cognition.
Understanding Team Adaptability: Initial Theoretical and Practical Considerations BIBAFull-Text 561-565
  Heather A. Priest; C. Shawn Burke; Danielle Munim; Eduardo Salas
Team adaptability is just beginning to be understood by researchers. Team training, team effectiveness, and adaptability have provided researchers with a pool of evidence that can be leveraged into meaningful team adaptability research. However, team adaptability is different from individual adaptability. Teams have processes that individuals do not. Furthermore, team adaptability refers to more than just effective performance. The following paper identifies 2 team processes that past literature indicates is important to adaptability (feedback and shared mental models). Theoretical issues and practical training issues are examined to help determine their role in adaptive teams.
The Utility of Mental Model Assessment in Diagnosing Cognitive and Metacognitive Processes for Complex Training BIBAFull-Text 566-568
  Sandro Scielzo; Stephen M. Fiore; Haydee M. Cuevas; Eduardo Salas
This paper illustrates the utility of mental model assessment in discriminating between high and low performers in terms of cognitive and metacognitive processes. Distinct computer-based knowledge elicitation methods were utilized to assess the acquisition of different knowledge types as well as the development of participants' mental models when training for a complex task. Additionally, participants' metacognitive accuracy was also measured. Results suggest that mental model assessment is diagnostic of knowledge acquisition for a complex task and mental model accuracy is related to accuracy in metacognitive processes.
Adaptation of Team Structure of Trauma Resuscitation Teams BIBAFull-Text 569-573
  Yan Xiao; F. Jacob Seagull; Colin F. Mackenzie; Katherine Klein; Jonathon Ziegert
We analyzed the debriefing sessions of real-life trauma resuscitation teams during the most intensive period of resuscitation: the first 30 minutes of patient admission to a trauma center. The debriefing sessions were from participants reviewing their performance in videotaped trauma resuscitation. Nineteen videotaped cases were reviewed in 37 debriefing sessions. Adaptation of team structure was noticed in response to task urgency and criticality, even though there was a preference for teams to maintain a hierarchical structure. We propose a set of archetypes of team structures based on the debriefing session and discuss how the archetypes could be used as a way to capture how teams adapt their structures.

COMMUNICATIONS: Cheeseburgers, Cocktail Parties, and Segregated-Multiple-Talker-Scanpath Hors D'Oeuvres [Lecture]

Gender in the Cocktail Party Effect: Listener, Target Speaker, and Distractor Genders Examined BIBAFull-Text 574-577
  Catherine R. Harrison; Robert S. Bolia
This study was designed to identify any effects of listener gender in the "cocktail party effect," in which the gender of target and distractor voices has been shown to effect a listener's ability to detect and correctly respond to commands given in a multiple simultaneous talker task. Two experiments demonstrated that although there is no main effect of listener gender in any performance measure, the gender of the listener does interact with the genders of the target and distractor talkers in some conditions. This finding is potentially relevant to the customization of acoustic displays for maximum effectiveness with users of either gender.
Design Approach does affect Customer Behavior: Action-Objects Increase Cut-Throughs BIBAFull-Text 578-582
  Robert R. Bushey; Kurt M. Joseph; John M. Martin
This paper investigates the impact of touch-tone IVR design styles on user behavior. The design of the touch-tone IVR systems is a critical component of delivering customer service. A well-designed system allows the customers to accomplish their goals and sets a positive tone to their interaction with the organization. Four design styles were considered: Action-Specific Object, Action-General Object, Specific Object, and General Object. Three user behaviors were considered: Cut-Through, Full Menu, and Beyond Full Menu. A usability study was conducted to quantify the impact of design styles on user behavior. Results indicate that design style does impact user behavior. The Action-Specific Object style produced the most Cut-Through behaviors and the fewest Beyond Full Menu behaviors compared to the other design styles. The results from this paper suggest that the interface design style should match the customer's mental model.
The Effects of Bold Text on Visual Search of form Fields BIBAFull-Text 583-587
  Kurt M. Joseph; Benjamin A. Knott; Rebecca A. Grier
This paper provides an analysis of a text-formatting issue that was revealed during usability tests of an enterprise software prototype being developed by a telecommunications company. Usability test results indicated that search times for information were longer than expected when form fields displayed field identifiers in a non-bold format and field values in a bold format. This unexpected finding prompted further examination of the text formats used in the enterprise software. Four different text-formatting conditions were created and tested using 32 participants. These conditions were as follows: 1) Non-Bold Field Identifier/Non-Bold Field Value, 2) Non-Bold Field Identifier/Bold Field Value, 3) Bold Field Identifier/Non-Bold Field Value, and 4) Bold Field Identifier/Bold Field Value. Participants performed a search task using an interface that approximated what was developed for the enterprise software. Measures of search time, accuracy and scan path indicated that performance was best for the Bold Field Identifier/Non-Bold Field Value condition. The results are discussed in terms of potential cost savings, and an additional study is proposed.
Segregation of Multiple Talkers in the Vertical Plane: Implications for the Design of a Multiple Talker Display BIBAFull-Text 588-591
  Ken I. McAnally; Robert S. Bolia; Russell L. Martin; Geoff Eberle; Douglas S. Brungart
Three experiments were conducted to evaluate the effect of spatial separation of multiple talkers in the vertical plane on speech intelligibility. The first experiment demonstrated a release from masking due to separation in the median plane, and that this release was not due to the presence of residual interaural time differences (ITDs). The second experiment showed that this release corresponded to an increase in signal level of 1.3 dB. The third experiment demonstrated that the increase in intelligibility due to separation in elevation and that due to separation in azimuth were not additive. Results are discussed in terms of their implications for the design of spatial audio displays.
Voice-Activated Dialing or Eating a Cheeseburger: Which is more Distracting during Simulated Driving BIBAFull-Text 592-596
  James W. Jenness; Raymond J. Lattanzio; Maura O'Toole; Nancy Taylor
We measured simulated driving performance for 26 participants who drove a fixed distance while continuously eating a cheeseburger, operating an automobile CD player, reading directions, or using a voice-activated dialing system to place calls on a mobile phone. Performance was also measured while participants drove without doing other tasks. Participants made the most lane-keeping errors, minimum speed violations, and glances away from the road while reading and while operating the CD player. They made significantly fewer driving errors and glances while voice-dialing the mobile phone or eating, although in both of these conditions they made more driving errors and glances than they did when driving without doing any other activity. We conclude that for simulated driving, placing calls using a voice-activated dialing system is as distracting as eating a cheeseburger, but both of these activities are less distracting than continuously operating a CD player or reading directions.

COMMUNICATIONS: Communication Posters

An Analysis of Telephone Messages: Minimizing Unproductive Replay Time BIBAFull-Text 597-601
  Michael D. Fleetwood; Danielle L. Paige; Chris S. Fick; Kenneth R. Laughery
This paper reports the results of a research project to study the nature and structure of phone messages and the design characteristics of phone messaging systems that would optimize the retrieval of relevant message information. Of particular concern with respect to the structure of a phone message was the location of a phone number left in the message. In order to replay any portion of a message, most messaging systems require the user to listen to the message from its beginning. Because it was found that phone numbers are typically left towards the end of a message, such a system is quite inefficient. One proposed solution is the implementation of a "back" button. A simple equation is employed to optimize the length of time encompassed by the back button, which would result in substantial time savings to users at least 17 seconds per message in which it was used. The ramifications of such time savings are discussed.

COMPUTER SYSTEMS: Multimodal Input [Lecture]

Longitudinal Study of the Effects of an Adjustable Ergonomic Keyboard on Upper Body Musculoskeletal Symptoms BIBAFull-Text 602-606
  Alan Hedge; Mark Goldstein; Lawrence Hettinger; Cari Varner; Don Silva; Jean Malafronte; Chuck Goodyear
A longitudinal study assessed the differential impact of standard and adjustable ergonomic keyboards on musculoskeletal symptoms among 71 computer users over a six month period. A total of 73 subjects participated: 34 subjects used a standard, flat keyboard and 37 used an adjustable, ergonomic keyboard. Subjects completed weekly surveys of perceived keyboard comfort, and body discomfort, along with other items. The ergonomic keyboard was rated favorably and for users there were significantly improvements neck, shoulder and arm comfort.
Pointing Stick versus Touch Pad: Working Together BIBAFull-Text 607-611
  David A. Sawin; Aaron M. Stewart; Jeffrey A. Calcaterra
Pointing sticks and touch pads remain the leading integrated pointing devices incorporated into notebook computers. Manufacturers have implemented dual point designs that include a pointing stick and touch pad on the same system to accommodate polarized preferences for pointing devices among users. Study of dual point designs analyzed the individual devices and identified strengths and weaknesses of combined designs. Findings indicate that with certain system attributes held constant, advanced technologies for pointing stick and touch pad produce near equal performance results and confirm hypotheses from previous research that user device preference and prior learning are key-contributing variables. Different types of pointing stick and touch pad technologies also lead to varying performance and preference results. In addition, users' abilities to transition to an alternate device depend on the device used during prior learning. Data suggests that unless device design is optimized for use of both devices, dual point designs may degrade performance and satisfaction of at least one component device when compared to similar metrics of the same device from single point designs.
When Should Computers Talk: Using Multiple Resource Theory to Determine Whether to Add Synthetic Speech to a User Interface BIBAFull-Text 612-616
  Patrick M. Commarford; Katherine A. Wilson; Kay M. Stanney
In an effort to maximize user performance and satisfaction, developers have added synthetic speech output to many computer interfaces. Using Multiple Resource Theory as the foundation, the purpose of this paper is to help determine under which conditions the addition of speech to an interface will be beneficial. Participants used a speech enhanced or control interface to complete a verbal and a spatial task. Results demonstrate that the simultaneous presentation of information via synthetic speech can be detrimental to performance on a verbal task and to user satisfaction. No performance or satisfaction differences were found for the spatial task. This paper concludes with design guidelines and suggestions for future research.
An Evaluation of Text-Entry in Palm OS Graffiti and the Virtual Keyboard BIBAFull-Text 617-621
  Michael D. Fleetwood; Michael D. Byrne; Peter Centgraf; Karin Dudziak; Brian Lin; Dmitryi Mogilev
The handheld organizer or personal digital assistant (PDA) is rapidly becoming a popular organizational tool, and there is a need for evaluation of alphanumeric character entry on these devices. The Palm operating system, the most common PDA operating system on the market, uses two methods for character entry, an on-screen virtual keyboard and a single-character handwriting recognition system called Graffiti. An initial experiment was conducted to investigate the character entry rates of novice and expert users of the device for the two methods of input. Experts were found to reach an average rate of 21 words per minute (wpm) using Graffiti and 18 wpm using the virtual keyboard. Novices were able to use Graffiti at a rate of 7 wpm and the virtual keyboard at 16 wpm. These character entry rates are evaluated with respect to some theoretical limitations, a predicted rate of entry based on Fitts' and the Hick-Hyman laws for the virtual keyboard, and pen and paper printing for Graffiti. The potential gain for new character entry systems and opportunities for improvement are discussed.
Cursor Capturing Functions as an Aid for Target Selection in Mouse Operation BIBAFull-Text 622-626
  Jungchul Park; Sung H. Han; Huichul Yang; Minhaeng Cho; Jooyung Han
This study proposed two cursor capturing functions in mouse operation. One is to move the cursor over a target instantaneously (jumping function) when the cursor reaches around the target, and the other is to move the cursor over the target gradually (gravity function). The effects of cursor capturing functions were examined and compared with the normal condition (i.e., without the functions). Task completion times, number of errors, and subjective preferences were evaluated. The results showed that the gravity function had faster movement times and fewer errors than the normal condition. The gravity function was more preferred than the jumping and the normal condition.
Best Practices in Search User Interface Design BIBAFull-Text 627-631
  Marc L. Resnick; Jennifer Bandos
The Internet has become a powerful tool for information search and ecommerce. Millions of people use the World Wide Web on a regular basis and the number is increasing rapidly. For many common tasks, users first need to locate a Web site(s) containing needed information from among the estimated 4 trillion existing web pages. The most common method used to search for information is the search engine. However, even sophisticated users often have difficulty navigating through the complexity of search engine interfaces. Designing more effective and efficient search engines is contingent upon a significant improvement in the search user interface.
Current Issues and Research Related to the Development and Delivery of Interactive Electronic Technical Manuals BIBAFull-Text 632-635
  Katie Ricci; John Hodak
For very practical reasons, technical publications and tactical information for military systems are now delivered with, or are being converted to, electronic format. While Interactive Electronic Technical Manuals (IETMs) have been available for quite some time, many research issues remain. Among these is the need to provide alternative search technologies that quickly and easily allow system users to navigate through large amounts of technical documentation to find required information. Further, natural language interfaces can provide users with a hands-free, voice-activated interface that may significantly improve a user's ability to perform their job. Finally, the use of intelligent diagnostics and tutoring can allow users access to expertise and learning opportunities. The objective of this panel is to provide an overview and discussion of issues related to the use of IETMs and current research related to IETMs for performance support and training.

COMPUTER SYSTEMS: Distinguished Speaker [Invited Address]

Some Historical Roots of the Field of Human-Computer Interaction BIBAFull-Text 636-640
  Richard W. Pew
The paper will discuss two major themes. A new field, is often initially championed by a small set of visionaries. There are many individuals who qualify as HCI visionaries. I will mention the impact of only three, Vannevar Bush, J.C.R. Licklider, and Douglas Englebart. Second, while considerable progress has been made in understanding what makes computers hard to use and in developing methodologies that support making them easier to use, the pace of technological change has been so rapid that just when we think we have a handle on it, the technology changes and we have a new set of problems. I will touch on several eras: the batch processing era, the time-sharing era, the personal computer era, the internet era, and the handheld-wireless era that is merging into the ubiquitous computing era.

COMPUTER SYSTEMS: Methods and More [Lecture]

Extending the Heuristic Evaluation Method through Contextualisation BIBAFull-Text 641-645
  Jarinee Chattratichart; Jacqueline Brodie
This paper proposes an extension to the heuristic evaluation framework to help overcome some of its limitations. We describe the addition of a contextualised layer, called the 'usability problems profile', to improve the reliability of the method's findings. We present the results of an experiment showing that evaluators -- even novices -- can produce more consistent and reliable evaluation results through adding a contextualised layer to the heuristic evaluation method. This extended method we call HE-Plus. In the experiment discussed, ten novice evaluators assessed a web site's usability. Five were using heuristic evaluation and five HE-Plus. The group that used the HE-Plus method spent less time in evaluation, found more usability problems, and found more overlapping problems than the group that used the original heuristic evaluation method. An in-depth 'usability problems profile' for the web site was derived from analysing the experimental data. The implications of this improved profile are discussed.
The Automated Card-Sort as an Interface Design Tool: A Comparison of Products BIBAFull-Text 646-650
  Merrill J. Zavod; Donald E. Rickert; Steven H. Brown
The method of card-sorting is a very useful tool for interface design as it can help to uncover the mental models of users concerning the relationships among various interface items (links, menu choices, etc.). However, methodological difficulties associated with traditional sorting procedures such as time and space requirements, as well as tedious data analyses, have limited the practical utility of card-sorts. Some software tools have emerged that purport to automate the card-sorting procedure, as well as analysis of results, in order to attenuate or eliminate these difficulties. Three tools available for free download from the Internet were chosen for review. The tools were compared and contrasted in terms of efficiency and effectiveness, from the standpoint of the researcher as well as the participant. While all three tools were found to save much time and effort over manual sorting procedures, each also carries with it a set of unique capabilities and limitations, leaving open the possibility for improved automated sorting tools in the future.
User's Delay Perception and Tolerance in Human-Computer Interaction BIBAFull-Text 651-655
  Enlie Wang
This paper focuses on user's delay perception and tolerance in a simulated computer supported cooperative work (a special case of HCI) environment, as well as the non-technological factors affecting user's delay tolerance. Five factors (gender, Type-A personality, task-type, difficulty level and time delay) were investigated by a mixed 2 (male vs. female, between-group) &times 2 (object search vs. budget calculation, within-group) x 2 (hard vs. easy, within-group) factorial experimental design. Type-A personality and time delay were nested in gender and treatment respectively. Results showed that users could estimate 2-6 second delay accurately, but would underestimate shorter delays (<2 seconds) and overestimate longer delays (>6 seconds). MANOVA analysis indicated that task-type, difficulty level and time delay were major factors affecting user's delay tolerance. We also found some important interaction effects between independent variables. The findings suggest that users can adjust their delay tolerance based on the context information such as task-type and difficulty level.
A Development Environment and Methodology for the Design of Work-Centered User Interface Systems BIBAFull-Text 656-660
  Wayne Zachary; Robert G. Eggleston
Work Centered Support System design represents an approach to the development of user interface application as an integrated, multi-faceted active and passive aiding system. Several successful instances of WCSSs have been developed using largely labor-intensive hand analysis and software coding methods. Here we describe a well-formed analysis, design, and implementation development environment, called the WIL Application Toolkit (WAT), as a work-centered development support aid for one type of WCSSs. The design principles and architectural properties of the WAT are discussed in the context of a design methodology. These aiding tools for interface system development is expected to improve WCSS design, shorten develop time, and improve sustainability of released interface products.
High-Fidelity or Low-Fidelity, Paper or Computer Choosing Attributes When Testing Web Prototypes BIBAFull-Text 661-665
  Miriam Walker; Leila Takayama; James A. Landay
Interface designs are currently tested in a mixture of fidelities and media. So far, there is insufficient research to indicate what level of fidelity and media will produce the best feedback from users. This experiment compared user testing with low- and high-fidelity prototypes in both computer and paper media. Task-based user tests of sketched (low-fidelity) and HTML (high-fidelity) website prototypes were conducted in each medium, separating the testing medium from other factors of prototype fidelity. We found that low- and high-fidelity prototypes are equally good at uncovering usability issues. Usability testing results were also found to be independent of medium, despite differences in interaction style. Designers should choose whichever medium and level of fidelity suit their practical needs and design goals, as discussed in this paper.

COMPUTER SYSTEMS: Computer Systems Posters

Land Warrior: Effects of Size of Keyboard on Speed and Accuracy of Data Entry BIBAFull-Text 666-669
  Christopher A. Collins; Darin G. Howe; Michael D. Matthews
The U.S. Army is implementing the Land Warrior (LW) system for use by individual infantry soldiers and their leaders. Among its many features, this system includes a wearable computer that allows soldiers and their leaders to communicate digitally. The principle method of data entry for this system is through a miniature keyboard that attaches to the user's forearm. The current experiment compared data entry speed and accuracy with the small (16 cm x 8 cm) LW (version 0.6) keyboard and a standard sized (45.5 cm x 17 cm) keyboard, with either one or two-handed data entry. The participants were 32 U.S. Military Academy cadets enrolled in a general psychology course. For speed data, there were significant main effects for both keyboard size and hands, and a significant interaction between the two variables. For accuracy measures, a significant main effect for hands was found. In general, participants were faster with the large keyboard, and more accurate with one hand, regardless of size of keyboard. Practical implications for LW implementation are discussed.
Perceptual Cues and Subjective Organization in a Virtual Information Workspace BIBAFull-Text 670-674
  Todd M. Eischeid; Mark W. Scerbo
The present study examined the effectiveness of three types of virtual desktop displays with varying degrees of perceptual cues: two-dimensional (2D) display, three-dimensional (3D) display without motion, and 3D display with motion parallax. It was expected that performance would improve as the number of perceptual cues increased. Participants were asked to search for documents either with an organizational scheme they created themselves or with a preconstructed arrangement. As expected, those who organized their own desktops performed better than those using a preconstructed arrangement; however, these effects were moderated by cue condition. Differences among the cues had no effect on subjective organization. However, searching a preconstructed arrangement benefited from a 2D representation. These findings suggest that a 3D representation may be ill suited to tasks in which semantic material is stored in a virtual information space.
An Integrated Methodology for User Interface Design: Human Factors in Use Case Driven Development Process BIBAFull-Text 675-679
  Qian Li
Human factors has provided many applicable theories and techniques to analyze user requirements, design user interfaces, and conduct evaluation of usability in software development. However, it is common that contributions made by human factors practitioners are not incorporated in this development process, which impairs the ability of human factors practitioners to have significant impact in cross-functional teams.
   This paper reviews the possible reasons that human factors efforts are frequently ignored in software design and development and proposes a conceptual framework for the integration of the methods and tools from both the user-centered design approach and the use case driven process to take advantages of the merit and recent progress in both human factors and object-oriented technology.
A Study of Electronic Annotation on Web Documents BIBAFull-Text 680-684
  Pei-Luen Patrick Rau; Sho-Hsen Chen
This study develops an electronic annotation system, allowing users to annotate on hypertexts, to build up knowledge structure, and to browse instructions provided by the system administrator or the instructor electronically. The electronic annotation system is a distributed World Wide Web application based on HTTP access and allows annotations on HTML documents. The major functions of the electronic annotation system include highlighting texts, inserting and editing annotations, and organizing and presenting annotations hierarchically. The five interactive components of the electronic annotation system are Main Tool Bar, Hypertext, Annotation Editor, Hierarchy Viewer, and Instruction Viewer. A user test was conducted to investigate the effect of the location of electronic annotating (Annotation Editor) on reading performance in terms of recall and degree of satisfaction.
Reading from a Palm Pilot Using RSVP BIBAFull-Text 685-689
  Mark C. Russell; Barbara S. Chaparro
This study examines the feasibility of using the text presentation method known as Rapid Serial Visual Presentation (RSVP) as a means of optimizing reading on small screen interfaces. Participants read text on a hand-held device in both the page-like format and at various presentation rates in RSVP. Reading comprehension, user satisfaction, and format preference were examined as dependent variables. Results showed: (1) there were significant differences in comprehension between the RSVP presented at 250 wpm and the higher speeds of 450 and 650 wpm; but (2) there was no significant difference in comprehension scores between the RSVP at 250 wpm and the page condition. Participants were able to comprehend text presented via RSVP at 250 wpm and the page format equally well. Despite this comparable performance between these formats, participants were generally less satisfied with the RSVP, and preferred 250 and 450 wpm presentation rates significantly more than 650 wpm.

CONSUMER PRODUCTS: Articles

First Annual User-Centered Consumer Product Design AwardAward BIBAFull-Text 690-691
  Dianne L. McMullin; Stan Caplan
The Consumer Product Technical Group (CPTG) is sponsoring the first annual user-centered consumer product design competition emphasizing product design and/or the methods used to specify and achieve the design. Emphasis is placed on innovative and user-centered approaches to Human Factors and Industrial Design.
Human Factors at the U.S. Consumer Product Safety CommissionPanel BIBAFull-Text 692-694
  Robert B. Ochsman; Hope E. Johnson; Celestine Kiss; Michele R. Marut; Jonathan Midgett; Timothy P. Smith
The Human Factors Division at the U.S. Consumer Product Safety Commission is an eclectic group, reflecting the multidisciplinary demands typically made upon an HF organization. The objective in these five presentations is to paint a picture of the full spectrum of human factors practiced in this unique government regulatory agency. The participants will each describe their work and illustrate the day-to-day characteristics of their human factors analyses. The range of discussions will address the overlay and integration of professional practice into policy, the regulatory environment, litigation support, and representation of the Agency to the interests of corporate, consumer, trade, and standards organizations.

CONSUMER PRODUCTS: Physical Considerations for Consumer Product Design [Lecture]

Universal Access in Practice: Usability Evaluation of Cellular Telephones for Users with Disabilities BIBAFull-Text 695-699
  Aaron M. Mooney; Maury A. Nussbaum; Tonya L. Smith-Jackson
Cellular telephones provide a portable means of communication and facilitate many communication tasks in daily life. Persons with disabilities, however, have limited access to these devices, which may be due to product designs that do not always consider their needs. Usability evaluations can identify the needs and difficulties when using cellular telephones, and those with disabilities are also likely to benefit from focused evaluations. The usability of cellular telephones was investigated among those with visual and upper extremity disabilities. Both objective and subjective evaluation methods were used to determine the effects of several telephone display and keypad design features. Lateral key pitch is reported here. Objective and subjective measures were similar among participant categories, with the 12 mm and 13 mm levels of lateral pitch generally the best across all measures. Results suggest keypad design features to consider when designing accessible cellular telephones. Universal design implications are also discussed.
Optimal Balancing of Product Design Features: A Case Study on Mobile Phones BIBAFull-Text 700-704
  Sang W. Hong; Kwang J. Kim; Sung H. Han
The design process to make a product that appeals to consumers should consider their various preferences (e.g. user satisfaction dimensions) simultaneously. That is, a key problem in product design is to select a set of optimal design values that would result in a product satisfying the various user satisfaction dimensions. This is one of the optimal balancing problems. However, it is very difficult for product designers to solve this optimal balancing problem in a quantitative manner. This study suggests a systematic method for solving these problems based on the multiple response surface (MRS) methodology and demonstrates the applicability of the proposed method through a case study on mobile phones. Three different optimal design settings for a total of 31 mobile phone design variables were analyzed and validated based on an optimization performance test and similarity test.
Human Factors Design Considerations of Alarm Clocks BIBAFull-Text 705-709
  Raymond W. Lim; Michael S. Wogalter
Advances in technology have allowed computers and peripherals to become more affordable and useable. Technology is also trickling down and being integrated into other consumer products such as those found in the home, such as alarm clocks. Two studies examined the desirability of various features that have or could be incorporated into alarm clocks. In Study 1, 378 people evaluated the importance of various features that have or could be incorporated into alarm clocks. They were also asked to report other features not listed. Study 2 was similar except a larger list of potential features was included. Both studies indicated that there are several features considered more important (e.g., digital face, independent buttons to set hours and minutes, low price) than others (e.g., traditional analog clock face, cassette player). Also, feature importance differed depending on gender and undergraduate/non-student groups. Factor analyses revealed that ergonomic aspects were being considered with respect to feature desirability. Implications for human factors/ergonomics issues are discussed including specific suggestions for alarm clock designs and other electronic consumer products.
Human Factors Considerations for High Chair and Stroller Child Restraints BIBAFull-Text 710-714
  Neil D. Lerner; Richard W. Huey; Carolyn Meiers
Falls from high chairs and strollers represent a major childhood hazard. While such products normally include some form of restraint system, their effectiveness may be limited. This research analyzed human factors causes of restraint system failures and recommended design and voluntary standards improvements. Product profiles were developed describing the range of product types, features, users, modes of use, child behaviors, adult caregiver behaviors, and characteristics of restraint failure incidents. Causal analyses then identified eleven primary incident scenarios involving restraint failure. These scenarios in turn were related to six fundamental movements. To the extent a product affords the opportunity for these movements, the effectiveness of the restraint system is reduced. Analyzing the problem in terms of movement affordances, a cross-cutting set of fundamental design issues emerged. These issues suggested a variety of design recommendations for specific product features including belts, seat compartments, crotch restraints, feeding trays, leg restraints, footholds, and barrier devices.
Band Saw Safety System BIBAFull-Text 715-719
  Susan Nosacka; Rachel Gumpenberger; Maggie Kubit; Bao Tran
The scope of this project was to produce a complete prototype of an electromechanical safety system that (1) detects human contact with the saw blade, (2) interrupts power to the saw motor, (3) actuates a firing system, and (4) abruptly stops the travel of the blade in order to minimize physical injury. The specific application for the project was a 12.7 mm wide, 0.5 mm thickness Ridgid saw blade (Part # 03991) mounted on a Ridgid 14" vertical band saw (Model #BS 1400). Through engineering analysis and several design iterations, a wedge-brake mechanism was developed and integrated with an electronic control system developed by SawStop. Upon completion of the nine-month project, the prototype was able to stop the motion of the saw blade in approximately fifteen milliseconds (ms). With this stopping time, it is estimated that the operator would experience a 4.8 mm (3/16 inch) depth of cut. Thus, first aid or a doctor's visit would be required rather than emergency hospitalization. The final project report included recommendations for further development.

CONSUMER PRODUCTS: Psychological Considerations for Consumer Product Design [Lecture]

Quantifying Customer Perception of Product Harmony Using Kansei Engineering Method BIBAFull-Text 720-724
  Lijian Zhang
Vehicle interior harmony has drawn increasing attention from customers in recent years. Kansei Engineering is an effective approach to quantify customers' perception of harmony, and to correlate it to design parameters of the products. Herein, we investigated the customer perception of the visual aspects of commercial truck door interior design using classification methods. This article describes how these visual impressions are related to design elements using quantification theory, a commonly used method in Kansei Engineering. The results reveal that trim material, shape, color, window shape, and map pocket are design elements that strongly affect the perception of "elegance" and preferences of truck drivers. The results also showed a significant difference between the perception of the truck drivers and that of design engineers.
Creativity Increases through Top-Down Design Procedures BIBAFull-Text 725-729
  Martin G. Helander; Dag Caldenfors
Finke's notion of preinventive structure in top-down design was tested using Suh's methodology for top-down axiomatic design. Two groups of experimental subjects designed controls and displays for an "intelligent" automobile. One group was instructed to consider functional requirements and derive their design in a top-down fashion. The other group was also informed about functional requirements, and design methodology but was not instructed to use any particular design procedure. The first group produced significantly better designs than the second group -- they were more creative, more practical and fulfilled design goals better. Top-down reasoning with careful consideration of functional requirements generated better design. Suh's methodology has an extra bonus, which is in agreement with Finke; it forces a slow deliberation of design features.
On the Reading of Product Owner's Manuals: Perceptions and Product Complexity BIBAFull-Text 730-734
  Brad Mehlenbacher; Michael S. Wogalter; Kenneth R. Laughery
This research focuses on the self-reported use of owner's manuals for automotive vehicles. The results indicate that owner's manuals are frequently not read. Nevertheless, people prefer owner's manuals to electronic presentations of the same product information. Implications for facilitating reader use of product documentation are discussed.
The Effects of Product, Signal Word, and Color on Warning Labels: Differences in Perceived Hazard BIBAFull-Text 735-739
  N. Clayton Silver; Kelly L. Drake; Zahra B. Niaghi; Aubrey C. Brim; Otto Pedraza
Signal words, such as DANGER, WARNING, and CAUTION are often used on consumer products to connote various levels of hazard. Each of these signal words is usually printed in a color (e.g., white on a dark background) in order to potentially increase saliency or aesthetics. Hence, there is a potentially significant interaction of signal word, color, and product type on perceived hazard. Warning labels for muriatic acid, Xtra-Clean All Purpose Cleaner, and Crayola Crayons were factorially combined with signal word (DEADLY, DANGER, WARNING, CAUTION, and NOTE) and color of signal word (orange, blue, red, black) for a total of 60 conditions. A sample of 124 undergraduates rated each product warning on understandability, likelihood of compliance, carefulness, and attention-gettingness. Results indicated that muriatic acid had significantly higher hazard ratings than either the cleaner or crayons. Black connoted the highest level of hazard followed by blue, red, and orange. Furthermore, the order of perceived hazard from highest to lowest for signal word was DEADLY, DANGER, WARNING, CAUTION, and NOTE. Moreover, there appears to be an averaging effect in which muriatic acid with the signal word NOTE printed in orange produced the same connoted hazard level as the package of crayons with the signal word CAUTION printed in red. Implications for warning design are discussed.
Evaluation of Product Preference using Virtual Prototyping: Case Study of an Automobile Interior BIBAFull-Text 740-744
  Chul Woo Kim; Jungchul Park; Myung Hwan Yun; Sung H. Han; Hee-Dong Ko
The objective of this study was to develop a product evaluation method applicable to virtual prototypes and to apply the method to automobile interior design. Considering that virtual reality-based product prototypes could represent design alternatives comparable to physical prototypes, prototypes developed in virtual reality environments were employed as design alternatives. After a procedure to evaluate virtual prototypes was developed specifically for a virtual reality environment, the procedure was applied to the problem of automobile interior design. 34 subjects evaluated 32 different virtual prototypes generated from the combination of design element variations. Four categories of subjective impression were used to evaluate the 32 virtual prototypes: luxuriousness, comfort, harmoniousness, and controllability. ANOVA and multiple linear regression analysis were performed to specify design elements critical to customer preference and to interpret the relationship between design elements and subjective impressions. As the result, the shapes of frontal area including crash pad and center fascia, door trim and steering wheel were selected as important variables related to subjective impressions. The proposed evaluation method for virtual prototypes could be utilized as an alternative way of identifying the relationship between subjective impressions and design elements.

CONSUMER PRODUCTS: Consumer Products Posters

The Relationship between Sleep Quality and Mattress Types BIBAFull-Text 745-749
  Se Jin Park; Hyun Ja Lee
Information of sleep stage was one of the most important clues for sleep quality. The purpose of this study was to measure the effects of mattress types on sleep quality, the skin temperature and to estimate the subjective rating. The hypothesis was tested whether sleep quality was different when subjects slept on mattress suitable for the bodily shape or not. Polysomnography is basically the recording of sleep. The several channels of brain waves (EEG), eyes (EOG), chin movements (EMG) and heart (ECG) were monitored. Six subjects spent 6 days and nights in the laboratory and the data of sleeping 7h for each of 3 nights was analyzed. Mean skin temperature, deep sleep (III and IV), sleep efficiency, sleep latency and subjective ratings were significantly affected with mattress types. When subjects slept in comfortable beds, mean skin temperature was higher than that of uncomfortable bed. Their skin temperature of the lower body, sleep efficiency and the percentage of deep sleep were higher, too. The percentage of wake after sleep onset was lower when subject slept in a comfortable bed.
Competitive Usability Analysis of Phone Interface for Television Text Entry BIBAFull-Text 750-754
  Amy Swanson; Kristine Turville Delano
As consumer electronics become more interactive, designers are increasingly looking for novel ways to control the user interfaces. With market competition and fast-track time to market constraints, devices that have a familiar use and appeal while being new in application are seen as advantageous. This evaluation looks at the usability of the familiar phone interface for text entry on televisions. How will users initially perceive the concept of phone interface? Will the current cell phone method of text entry be transparent to users? How does it compare to other text entry devices? Results indicate that the phone interface device is initially highly acceptable to users but fails dramatically in usability.

DEMONSTRATIONS: Tools for Team Performance Capture, Team Knowledge Assessment, Motion in Virtual Displays, and Immersive Displays on the Cheap! [Demonstrations]

The Rate Tool: Multimedia Observation and Analysis of Teams BIBAFull-Text 755
  Stephanie Guerlain; Thomas Shin; Hui Guo; Reid Adams; J. Forrest Calland
We have developed a digital audiovisual recording and analysis system for studying team behavior. The system uses four computes to collect up to four video and eight audio signals. A separate software package is used to synchronize, view, analyze and score the audio/video streams.
Structural Knowledge Assessment with the Team Performance Lab's Knowledge Analysis Test Suite (TPL-KATS) BIBAFull-Text 756-760
  Raegan M. Hoeft; Florian G. Jentsch; Michelle E. Harper; A. William Evans; Devon G. Berry; Clint Bowers; Eduardo Salas
Card sorting and concept mapping are two popular techniques used for assessing structural knowledge. However, manual administration of these tasks has been cumbersome in the past. This demonstration serves as an introduction to the TPL-KATS -- Card Sort and Concept Map software tool developed at the Team Performance Lab at the University of Central Florida. TPL-KATS is presented as a possible solution to the problems of manual administration. The software contains computerized versions of both techniques, with automatic administration and scoring capabilities. This demonstration provides an introduction to the card sort and concept map tasks, and describes the basic need for this software tool. A full description of TPL-KATS -- Card Sort and Concept Map software is presented, along with a demonstration of its advantages over current techniques.
Configuring Multiscreen Displays With Existing Computer Equipment BIBAFull-Text 761-765
  Jeffrey Jacobson
An immersive multiscreen display (a UT-Cave) may be assembled from common home/office equipment which can be borrowed in most research settings. The simplest design requires two LCD projectors, three personal computers, the corner of a room, a network hub and cables. The required software is an inexpensive but graphically powerful computer game, Unreal Tournament (UT), and a freeware patch called "CaveUT." Unreal Tournament is partially open source and supports rapid authoring of visually rich virtual worlds, complex animations, and software modifications such as alternative physics or artificial intelligence. PC-based game hardware and game engines such as the one for UT deliver superior real-time graphics at a tiny fraction of the cost for traditional immersive multiscreen displays, such as the CAVE. While currently having fewer features, the UT-Cave, like the traditional CAVE-like displays, is useful for research in vehicle simulation, human balance, architectural simulation, novel human-computer interfaces and much more. Except for UT's game engine, which is very inexpensive, everything about the UT-Cave is free and open-source at "www.planetjeff.net/ut". UT-Caves with more screens have been assembled using the same basic design principles illustrated here. A sample experiment is presented which uses a four-screen UT-Cave controlled from the control program, "LabView."
Demonstration of a Motion Coupled Virtual Environment (MOCOVE) A Device for Reducing Spatial Disorientation in Uncoupled Virtual and Motion Environments BIBAFull-Text 766-770
  Keith W. Brendley; Joseph Cohn; Jed Marti; Paul DiZio
The U.S. Navy intends to field Virtual Environments (VE) aboard ships and submarines for training crews at sea and in harbor. The shipboard environment combined with a VE presents a challenge for reducing the side effects, most notably motion sickness, postural instability and spatial disorientation. The discrepancy between actual motion and perceived motion in the VE has been shown to be among the greatest contributing factors to side effects. The two environments, virtual and real, combine to create a highly provocative "motion discordant environment." This demonstration presents an approach for minimizing side effects. The approach creates a Motion Coupled Virtual Environment (MOCOVE) where physical motion is sensed and convolved with the VE scene. The resultant VE has been shown to reduce side effects in preliminary laboratory studies.

EDUCATION: Teaching HF and Web-Based Instruction [Lecture]

A Graduate Course in Human Factors and Aging: Engineering Gerontology BIBAFull-Text 771-773
  R. Darin Ellis
This paper discusses a graduate course that focuses on human factors engineering solutions for issues faced by older adults. The course has attracted students from a broad range of disciplines. The course content and format are discussed. Brief examples of student research projects are given. The ongoing challenges of teaching such as specific topic to such a diverse audience are discussed in closing.
An Empirical Study of Usability Testing: Heuristic Evaluation vs. User Testing BIBAFull-Text 774-778
  Enlie Wang; Barrett Caldwell
In this study, two different usability-testing methods (Heuristic Evaluation and User Testing) were selected to test the usability of a pre-release version of software searching for Science, Mathematics and Engineering education materials. Our major goal is to compare Heuristic Evaluation and User Testing in terms of efficiency, effectiveness and cost/benefit analysis. We found that Heuristic Evaluation was more efficient than User Testing in finding usability problems (41 vs. 10), while User Testing was more effective than Heuristic Evaluation in finding major problems (70% vs.12%). In general, Heuristic Evaluation appears to be more economic in finding a wide range of usability problems by incurring a low cost in comparison to User Testing. However, User Testing can provide more insightful data from real users such as user's performance and satisfaction.
Reusable Simulations and Interactive Learning Experiences in Human Factors Education BIBAFull-Text 779-782
  Steffen Werner; Andreas E. Finkelmeyer
Web-based teaching and multimedia tools in human factors education have become popular in the last few years. In this paper, we are proposing a straightforward extension of the current uses of the internet in the form of a clearinghouse of interactive learning experiences and simulations. Three sample simulations used in a course entitled "Technology, Design, and the Human User" offered through the Human Factors program at the University of Idaho will be used to illustrate the versatility and adaptability of simulations and interactive learning experiences once they have been constructed for one class. Our goal is to make this collection of educational materials available through a central website.
The Effects of a Web-Based System on Subjects with Contrasting Study Orientations BIBAFull-Text 783-787
  Pedro Z. Caldeira
The main goal of this study is to compare the impact of Web-based information on surface, deep and total learning, on satisfaction and on navigation information of subjects with different study orientations. Three subject groups were selected and each group included only subjects with a specific study orientation: A meaning study orientation, a reproduction study orientation and a disorganized study orientation. After studying a Webbased presentation on 'Global Warming', subject's performance was evaluated regarding surface, deep and total learning, satisfaction and navigation style. Results show that, first, subjects with a disorganized study orientation score lower on deep learning and on total learning than subjects with a reproduction study orientation and, second, subjects with a disorganized study orientation felt easier to navigate in the Web-system than subjects with a meaning study orientation (although they visit more pages and spend less time in each one than subjects with a meaning study orientation).
Predicting the Adoption of Web Media Objects for University Course Instruction BIBAFull-Text 788-791
  Kayenda Johnson
This research addresses university faculty's use of web media objects: text, images/graphics, animation, audio and video for course instruction. The purpose of this research was to determine, through multiple regression models, the most influential factors associated with faculty adoption of web media objects. Faculty adoption and implementation of web media objects for course instruction involves three stages: technology, pedagogy, and presentation style. Regression models were developed for each stage. The resulting multiple regression revealed that innovation characteristics: compatibility, trialability, and relative advantage are most important to consider for faculty adoption of web media objects in their course instruction. Guidelines are presented for advanced multimedia training developers and training support systems, and recommendations are made for improving the adoption of web media objects for university course instruction.
Teaching Techniques and Demonstrations: Let's Not Recreate the Wheel BIBAFull-Text 792
  Nancy J. Stone
As educators in human factors and ergonomics, we often struggle to find good examples that demonstrate the underlying psychological or ergonomic principles and how these principles are applied to HF/E problems. This symposium is an attempt to establish a basic format for presenting effective teaching techniques, strategies, and demonstrations. These five demonstrations require active participation of the students, make the HF/E principles more relevant, cost under 50, and require little more than everyday equipment available in most academic departments. After the presentations, a 20 to 30 minute discussion will ensue to identify 1) existing but undocumented demonstrations, 2) areas in which demonstrations are needed, and 3) additional sources of demonstrations.
Low-Technology Demonstrations of the Role of Peripheral Vision in Human Factors and Ergonomics BIBAFull-Text 793-797
  William F. Moroney
This paper provides two demonstrations that highlight the importance of peripheral vision issues in system design. The first demonstration concerns the ability of the visual system to detect motion, while the second addresses the impact of reduction of visual field on the perception of optical flow data. Educators can use these demonstrations as the basis for discussions about the design implications for warning displays, attention gathering devices, optical flow, off-axis accidents, aging, attention, and night vision goggles. These demonstrations can be used at both the undergraduate and graduate levels. Relevant research findings are also discussed, and references for further exploration of the topics are provided.
Computer-Enhanced Demonstrations of Simple Reaction Time BIBAFull-Text 798-800
  Andris Freivalds; Dongjoon Kong
As human factors (HF) educators, we often struggle to find good examples or inexpensive tools that allow us to demonstrate basic ergonomic principles. The following computer software allows us to HF educators to demonstrate a variety of basic cognitive not only in a lecture of laboratory environment but also at the convenience of the student who owns a personal computer. Specifically this demonstration will present the concept of a simple reaction time, but with the variations of using different color stimuli and a mouse button click for the response.
Computer-Enhanced Demonstrations of the Fitts' Tapping Task BIBAFull-Text 801-804
  Andris Freivalds; Dongjoon Kong
As human factors (HF) educators, we often struggle to find good examples or inexpensive tools that allow us to demonstrate basic ergonomic principles. The following computer software allows us to HF educators to demonstrate a variety of basic cognitive not only in a lecture of laboratory environment but also at the convenience of the student who owns a personal computer. Specifically this demonstration will present the Fitts' Tapping Task with the Index of Difficulty factor using an eye-hand coordination task but the variation of performing the movements with a mouse.
The Effect of Uncertainty on Reaction Time BIBAFull-Text 805-809
  Stanley Caplan
Using various card-sorting tasks, this class experiment shows how choice reaction time increases with the number of bits processed in tasks having familiar stimuli and one-to-one stimulus-response compatibility. Students deal decks of cards during four timed exercises into a specific number of piles according to color (2 piles), suit (4 piles), etc., which represent a different level of uncertainty measured by bits of information processed. A second deal is conducted without regard to suit, color, etc. to determine and remove movement time from the total deal time. The relationship of the resulting reaction time and bits is shown in a graph of data generated in real time from the students' four class exercises. This demonstration can be used to introduce the concept of information processing, to explore what experimental factors could contribute to the resultant time, and to discuss real-life choice reaction time applications.
Simulated Investigation of Hypothetical Accidents: Learning about Causation, Causal Reasoning, and Investigation Bias BIBAFull-Text 810-814
  Kathryn Woodcock
A multi-class session exercise was developed to provide experiential learning of principles of investigation bias and diagnostic reasoning while applying principles of logic in accident causation.

EDUCATION: Education Posters

Developing a Reusable Resource for Teaching Task Analysis BIBAFull-Text 815-819
  Liwana S. Bringelson; Tanya E. Morose; Carolyn G. MacGregor; Catherine M. Burns
Many of the skills required in the practice of human factors are "process-oriented" rather than "product-oriented"; this is challenging for human factors educators because it is often more difficult to teach process-oriented skills and concepts than product-oriented skills and concepts. The Centre for Learning and Teaching Through Technology [LT3] at the University of Waterloo, Ontario, Canada is involved in developing learning objects (also known as "learnware") to help faculty overcome instructional challenges associated with teaching processes. The learnware development model used by LT3, which enables learner-centered resources to be developed, for students, and by students, to teach about processes in various disciplines will be discussed. The Task Analysis learning object developed to overcome instructional challenges experienced by human factors professors in the department of Systems Design Engineering, will illustrate LT3's learnware development model. The development of Task Analysis learnware emphasizes how the application of iterative learner-centred design can aid in teaching fundamental concepts in human factors.
Spotlight on Educating Our Future Professionals: What Human Factors and Ergonomics Means to Students BIBAFull-Text 820-824
  Haydee M. Cuevas; Matthew Hilscher
One of the primary goals for members of the Human Factors and Ergonomics Society should be to increase student awareness of the opportunities found in the field of human factors/engineering psychology. By increasing awareness of our discipline, we can improve our chances of attracting bright, talented, and energetic students to the various undergraduate and graduate programs around the country, which can only serve to enrich our profession and benefit society. Toward this end, we asked students at different levels of education what human factors and ergonomics meant to them. First, we assessed the awareness of the concept ergonomics in college-bound high school seniors. Second, we surveyed undergraduate students about their awareness of human factors/engineering psychology as a viable major. Third, current human factors/engineering psychology undergraduate and graduate students were asked why they chose to pursue this field of study. Implications for promoting the discipline of human factors/engineering psychology are discussed.
Cognitive Work Analysis in Education and Training: Relating Pedagogical Methods to Course Objectives BIBAFull-Text 825-828
  Marvin J. Dainoff; Leonard S. Mark; Carrie Hall; Adam R. Richardson
A systematic research program is described that utilizes cognitive work analysis as an integrative framework within which pedagogical methods based on principles of cognitive science can be systematically harmonized with pedagogical objectives arising from the structure of course content. The test bed for the program was a course in introductory psychology. A work domain analysis was conducted which included both course content and pedagogical methodology. These analyses allowed a clear specification of learning objectives and a corresponding pedagogical to meet these objectives, along with a framework for employing appropriate technology and assessing effectiveness.
The Effort is Well Worth it: Finding Systems Projects for Human Factors Evaluation BIBAFull-Text 829-833
  Frances Atchley-Greene; Shawn M. Doherty
This paper outlines the exposure of students to real-world, hands-on capstone projects in the Human Factors domain. Multiple groups of students have been provided with the opportunity to analyze and evaluate human factors and system engineering projects provided by the local community businesses and public works departments. This paper summarizes the basic processes used in obtaining these projects and the response from both students and clients to these projects. In general, most students recognize the benefit of these projects and appreciate the opportunity to utilize their skills in a practical arena that goes beyond the traditional classroom. Clients that provide the projects are grateful for the assistance our students provide and look forward to future endeavors.

ENVIRONMENTAL DESIGN: Environmental Design Potpourri [Lecture]

Safer Home Stairways Application of Public Health Policies and Research Findings to the Development of Design Codes in the USA BIBAFull-Text 834-838
  Jake Pauls
In an admittedly personal professional perspective, roughly twelve months of events, beginning July 2001, are discussed in terms of the events' historic impact on environmental design of home stairways. Considerations of public health and ergonomics permeated these events, many of which could profoundly affect stairway usability and safety, especially at a time of increased concern about the personal, social and economic benefits of aging in place facilitated through Universal Design.
User-centered design of distributed meeting environments: An initial study of experienced and naive users BIBAFull-Text 839-843
  N. Delia Grenville; Brian M. Kleiner
In our study, a basic science approach was used to explore the constructs that defined the design of a distributed meeting space from the user's perspective. Although there is a body of literature in the group communication domain, the research in this multidisciplinary area has paid minimal attention to users' environmental preferences in the design of a meeting space. Fifty participants, half with experience and half without experience in distributed meetings, used foam-core components to create a design of their ideal distributed meeting space. Fourteen themes emerged from content analysis of responses to the post-task interview. These themes addressed the rationale participants used when creating their designs. There was a significant positive relationship between the experience level and the following design themes: visibility of displays, status, team collaboration, VTC (video teleonferencing) needs, and auditory clarity. There was also a significant positive correlation among the occurrences of several design themes.
Comparison of Design Requirements Methods for Monitoring Eating Patterns of Seniors in a Smart House BIBAFull-Text 844-848
  Young Sam Ryu; Robert C. Williges; Tonya L. Smith-Jackson; Jiyoung Kwahk
The Smart House technology introduced an intelligent home designed to monitor the health and well being of senior residents unobtrusively. As one of the most important components of the smart house technology, we are developing an online eating-pattern monitoring system to be incorporated into a Smart House. A combination of four needs assessment methods including focus groups, observation, questionnaire and document review was used to gather information from seniors to determine critical design requirements for the system. A framework of information and interface requirements was developed to compare the effectiveness of the four methods used in our needs assessment. All four methods provided useful design recommendations, but each method differed in terms of specification of information and interface requirements. Based on the classification and comparison of methods, other practitioners can determine tradeoffs and select relevant needs assessment methods for their particular application.
Determining User Needs for Community-Based Geospatial Information Technology Services BIBAFull-Text 849-853
  Barrett S. Caldwell
The State of Indiana is in the process of creating a set of database tools to allow improved access, sharing, and understanding of information about community-level resources for any location within the state. This paper describes developing efforts to identify the needs of users in local government, community planning, emergency response, and agricultural extension offices to utilize the growing technical capabilities of geospatial information systems to improve environmental quality and local resource utilization for citizens of the state.
Fractal Design Strategies for Enhancement of Knowledge Work Environments BIBAFull-Text 854-858
  James A. Wise; Richard P. Taylor
Converging lines of research suggest a deep linkage between cognitive and emotional processes and settings displaying a rich visual fractal structuring in the 1.3-1.5 dimensional range. Reanalysis of a previous empirical study on interior design inducing reduction of performance stress from knowledge work suggests that this fractal dimensionality of a cabin panel surface pattern was the key environmental modification affecting subjects. In natural environments, fractal dimensionality in this range is most often associated with sinuous watercourses, undulating horizon lines and branching tree structures, all of which had high survival value for human ancestors in our evolutionary history. Other empirical research indicates that cognitive performance associated with visual search and access to working memory can be improved by inducing a 'convergence to pattern' of fractal environmental structure and the neural processes to which it seems particularly attuned. These in turn imply significant fractal design enhancements for work settings which are either semi-isolated and/or confined for technology/ health / security reasons, or habitats in remote and harsh environments.
Immune Buildings Using Ergonomics and Environmental Design to Create Safe and Secure Settings Symposium BIBAFull-Text 859
  Alan Hedge
The horrendous events in September of last year, from airplane attacks on large buildings to bioterrorism in postal and other government facilities, raised awareness of the vulnerability many modern buildings to terrorist attack and the importance of designing safer buildings that impede terrorist activity and that can facilitate occupant egress at a time of crisis. This symposium will examine the role that Human Factors professionals can play in improving the design of Immune Buildings, designed to better protect occupants and minimize the risks of hostile activity. Four papers will be presented that will examine human factors contributions to new ways of thinking about buildings. The first paper by James Wise will describe approaches to de-opportunizing such undesirable behaviors and environmental design changes that can thwart vandalism, burglaries, bank robberies, physical and sexual assaults, and counterterrorist situations. The second paper by Jake Pauls will review opportunities for changing building designs to impede terrorist ingress and facilitate occupant egress in times of need. The third paper by Alan Hedge will review ways that building ventilation systems can be configured to minimize bioterrorist threats on indoor environments by implementing a concept of 'smart furniture'. The fourth paper by Eric Neiderman will examine the contributions that human factors can make to improving airport security.
De-Opportunizing Design and Its Lessons for Building Security and Counterterrorism BIBAFull-Text 860-864
  James A. Wise
Recent broad concerns for "Homeland Security" have renewed the field of 'hard' security design and directly resistant design strategies for buildings. However, there is an associated field of research and practice on 'soft security' design, which is equally applicable and less impacting on the general user populace. This approach works on the general principle of 'deopportunizing', which examines the explicit control loops that a malefactor must engage with the setting in order to carry out their intentions. Then explicit interventions are designed into settings in order to disable or frustrate such needed controls. The result is enhanced security without regular users being inconvenienced or often even noticing the interventions. This paper reviews the applications of such de-opportunizing environmental design to thwart vandalism, burglaries, bank robberies and physical and sexual assaults, and extends it to counterterrorist situations using Perceptual Control Theory, which provides the theoretical basis for its use.
Environmental Design Strategies for Building Egress BIBAFull-Text 865-869
  Jake Pauls
The events of September 2001, 2001, plus the events' technical and political aftermath have helped to identify an unfortunate lack of research into building evacuation. The relative dearth of research is ironic given evacuation's central role in mitigation for a range of emergencies and its prominence in environmental design requirements in building codes and standards. The field of human factors has much to offer, for example, in a philosophical or strategic focus on human-centered design as well in more-prosaic issues such as exit stair width and handrail provision. Much of the available research addresses fairly low-level ergonomic issues such as exit stair width in relation to egress capacity and the impact on evacuation time. In addition to more-sophisticated research into the relatively simple issues, ahead lies more-difficult research relating to strategic issues and the provision of information to building occupants in emergencies, occupants' situational awareness generally, and the many social interactions-in seldom-considered environmental contexts-that are at the heart of major evacuations of large buildings such as in the case of the World Trade Center.
Smart Furniture Workstation Technologies that Promote Health BIBAFull-Text 870-874
  Alan Hedge
The issues of protecting against airborne bioterrorism in essence are identical to those concerning protection against a wide array of indoor air pollutants. Consequently, solutions pioneered for improving indoor air quality should be applicable to promoting safety against bioterrorist attack. However, the design of a modern air-conditioned building reveals multiple points where air quality can be compromised. From a building systems standpoint is extremely expensive, if not impossible, to adequately police all possible entry points and to effectively treat all of the supply air using existing filter technologies. The use of smart furniture may offer a way to minimize the risks of worker exposure to airborne contaminants. It can also augment environmental information displayed to workers to generally improve the quality of the physical environment conditions. Smart furniture can play a significant role in the overall performance of an immune building.
Designing Airport Security Checkpoints of the Future BIBAFull-Text 875-879
  Michael D. Snyder; Eric C. Neiderman; Melissa W. Dixon
Aviation security checkpoints present a great challenge for designers. Paradoxically, they should not be a burden to innocent passengers, and yet they must be impenetrable by terrorists. Therefore, human factors engineers, security experts, and architects need to work together to design checkpoints to meet stakeholders' needs, as well as the competing demands of deterrence, detection, and throughput.

FORENSICS PROFESSIONAL: Issues in Forensic Human Factors

Punitive Damages Awards in Civil Litigation: Effects of Profit Information and Amount of Pain and Suffering Award BIBAFull-Text 880-884
  Kenneth R. Laughery; Danielle L. Paige; Michael S. Wogalter; Richard N. Bean
A study addressing jury decisions regarding punitive damages awards in civil litigation was carried out. Two issues explored were the fact that jurors typically do not have a good metric for assigning a value to such damages and the concept of "leakage." The latter concept refers to decisions regarding compensatory damages and punitive damages influencing each other; in the law they are supposed to be independent. Forty-two participants were given three scenarios describing accidents, injuries, liability outcomes, and the amounts of economic and non-economic (pain and suffering) awards. Their task was to decide on punitive damages awards. Two variables manipulated in the scenarios were the presence or absence of defendant profit information and the amount (high or low) of the pain and suffering award. Results indicated the main effects of the two variables were not statistically significant. A significant interaction between the profit-information and pain-and-suffering-amount variables indicated that when profit information was available, low pain and suffering awards led to higher punitive damage awards. When profit information was not available, high pain and suffering awards led to higher punitive damage awards. The results indicate that decisions regarding compensatory and punitive damages are not independent as the law intends; an outcome that may be due, at least in part, to the uncertainty associated with these types of decisions. These findings have implications for judicial procedures, particularly jury instructions.
Computer-Generated Interactive Displays as an Aid in Explaining Complex Accidents to the trier of Fact BIBAFull-Text 885-889
  Gary D. Sloan; G. David Sloan; John A. Talbott
Streimer (1973) proposed that information serves three functions: description, prediction, and persuasion. All three functions are important in forensic human factors. The purpose of this paper is to describe the use of an interactive computer graphic display (ICGD) in explaining the probable causes of an accident to attorneys, and, potentially, to the trier of fact. ICGDs appear well suited to demonstrating the functional relationship between components in complex systems. An example of ICGD used to explain what went wrong in the operation of a power press where a worker was electrocuted shall be presented.
Motorcyclists' Brake Operation, Motorcycle Brake Controls and a Case Study: The Need for Human Factors Engineering BIBAFull-Text 890-894
  Rudolf G. Mortimer
A survey was made of the braking techniques reportedly used by 180 motorcyclists in a variety of conditions. Overall, the motorcyclists indicated that they used both front and rear brakes in hard braking 75% of the time on dry pavement and 47% on wet, but in other conditions they mostly used the rear brake first or exclusively. That the rear brake is preferred is not surprising because of the design of the brake controls and other reasons. Reliance on the rear brake at the expense of the front wheel brake leads to reduced deceleration. A crash case study exemplifies the effect. Integrated brakes, in which each brake control simultaneously activates the brakes on the front and rear wheels, are indicated by good human factors design and by motorcyclist's braking performance and should improve safety, especially when the brakes incorporate antilocking mechanisms.
Behavioral Adaptation: Unintended Consequences of Safety Interventions BIBAFull-Text 895-899
  Stephen L. Young; J. Paul Frantz; Timothy P. Rhoades
Various types of safety interventions (i.e., design attributes, guarding, personal protective equipment, training, warnings, etc.) can be, and often are, used to enhance safety with products or in environments. However, a safety intervention introduced into a system can, as with other changes to a system, produce secondary effects that have the potential to reduce the safety of the system rather than increase it as intended. One such effect, discussed in the present paper, is that humans may adapt their behavior in the presence of a safety intervention and that this behavioral adaptation can create a continuum of effects ranging from a positive increase in safety to a net decrease in safety. Several examples of behavioral adaptation are provided and implications for human factors and safety professionals are discussed. This paper will help human factors and safety professionals assist others in seeing the need to consider potential implications of safety interventions as a result of behavioral adaptation.
Considerations for Developing a Consensus Standard for Safety Information in Product-Accompanying Literature BIBAFull-Text 900-904
  Stephen L. Young; J. Paul Frantz; Timothy P. Rhoades; Steven M. Hall
At their most recent meeting, the ANSI Z535 Accredited Standards Committee considered the merits and practicality of developing a standard regarding the presentation of safety messages in product-accompanying literature. Subsequent to the meeting, the committee voted to form a new subcommittee, ANSI Z535.6. The purpose of this new subcommittee is to develop a new standard to complement the existing Z535 standards by dealing with various aspects of the provision of safety information in collateral materials such as manuals, instruction books, troubleshooting and repair manuals, etc. The present paper serves to provide an early notice to the human factors community of the ANSI Z535.6 standards-development activity. This paper also presents a preliminary analysis of (a) some existing standards, recommended practices and guidelines addressing safety information in various types of product manuals and (b) the ways in which safety information is currently presented in various product manuals.

FORENSICS PROFESSIONAL: Forensics Professional Posters

Allocation of Responsibility for Medication Errors BIBAFull-Text 905-909
  Danielle L. Paige
This study was designed to assess perceptions of responsibility for consumer safety while using prescription medication. Twenty-five university students were presented with four scenarios depicting an adverse outcome due to negligence involving the administration of a prescription medication. Responsibility could be assigned to the physician, the pharmacist, or the consumer (patient). Scenarios were framed either with no information regarding who committed the error, a physician error, or a patient error. The consumer was given significantly more responsibility overall, mean = 54.59 percent for consumer, compared to 34.48 percent for physician. The percent responsibility allocated to the pharmacist was not a focus of this study as its mean allocation was small, mean = 10.92, and did not vary with experimental manipulations. The shift in responsibility assigned to the consumer when the scenario highlighted consumer error was significantly greater than the corresponding shift in responsibility assigned to the physician in the physician condition.
Traction Considerations During Stairway Descent BIBAFull-Text 910-914
  Robert H. Smith
Investigations of actual pedestrian descent slips on dry stairway-tread nosings indicate that additional analysis of traction requirements during such activity is warranted. Limited biomechanical-traction-demand testing utilizing force plates on stairs have been conducted. Results from this work have been used to characterize currently accepted safety factors for stair-tread slip resistance as generous. However, two issues of relevance have not been considered. One is the angle of foot contact with the nosing, which can produce a rampeffect. Ramp descent necessitates provision of greater slip resistance than does horizontal ambulation. Another is elastomeric friction behavior by shoe heel-and-sole materials in contact with treads. In classical metallic theory, the coefficient of friction is directly proportional to the developed frictional resistance force divided by the applied normal load. This is not always so with elastomeric materials. With some elastomers, the friction coefficient decreases as applied normal forces increase. Because of this inverse response, focus widens to include both traction demand by the pedestrian and traction production in the footwear. The potential importance of foot-contact angles and the elastomeric-friction mechanism in stairway descent are assessed.
Sexual Harassment: An Organizational Safety Issue BIBAFull-Text 915-919
  Alison G. Vredenburgh; Ilene B. Zackowitz
Sexual harassment is a serious workplace safety issue. Central to all definitions of sexual harassment is the abuse of actual or perceived power over another individual. At the workplace, harassment creates a fearful and unsafe work environment. If organizational policies, procedures and practices do not prevent sexual harassment, an unsafe condition for employees may result and those organizations may be held liable for the damages. This paper presents a multidimensional study of harassment as a workplace safety issue. The forensic aspects of sexual harassment will be addressed. Two case studies will illustrate the depth and breadth of the harassment problem as an organizational safety issue. Finally, a study will be presented. Ten individuals who have experienced sexual harassment were interviewed in depth regarding their experiences. This multidimensional approach will illustrate that harassment is a workplace safety issue that can result in physical injury, emotional and professional damage to the victim as well as negative consequences to the organization.

GENERAL SESSION: Thinking About, and In, the World

Road Rage: User-Reported Antecedents and Potential Solutions BIBAFull-Text 920-924
  Tonya L. Smith-Jackson; Michael S. Wogalter; Eric F. Shaver
Road rage (intentional high risk driving behavior) is a factor that increases the likelihood that a driver will be involved in a vehicle crash. The focus of this study was to determine potential antecedents of road rage and methods to prevent road rage. A sample of 372 participants were surveyed. Based upon responses, participant profiles were established to analyze the data. Analyses using Chi-square and Fisher's Exact test revealed a significant negative relationship between age and the tendency toward aggressive driving, particularly tailgating. In addition, content analysis revealed a number of potential antecedents of and solutions to road rage. Human factors implications are discussed.
Cognitive Performance Assessment for Stress and Endurance BIBAFull-Text 925-929
  Linda L. Mullins
The U. S. Army Research Laboratory's stress research and cognitive readiness program focuses on developing methods that reliably measure stress and assess the effects of stress on performance and cognitive processing. The evaluation of changes in cognitive processing related to individual stress levels enhances the effectiveness of this area of research. This paper describes a Cognitive Performance Assessment for Stress and Endurance (CPASE), a battery of tests representing a range of skills that are sensitive indicators of human performance in stressful environments: memory recall, logical reasoning, working memory, and spatial manipulation. These tasks were selected through a literature search for functions that are sensitive to the effects of stress and could be generalized to higher level cognitive functioning. The focus was to develop a non intrusive battery that was amenable to testing a large group of participants in a field setting in a short amount of time. This battery has been successfully used to evaluate soldier performance during sleep deprivation (Fatkin, Knapik, Patton, Mullins, Treadwell, & Swann, 2000) and in the evaluation of military equipment (Glumm, Branscome, Patton, Mullins, & Burton, 1999).
Towards a Taxonomy of Human Factors Research: A Multi-Dimensional Approach BIBAFull-Text 930-934
  Renee Chow; Klaus Christoffersen; Oscar Guerra
This paper proposes an overarching structure for describing and organizing the content of human factors and ergonomics (HF/E) research. Instead of a uni-dimensional, topic-based approach to classification, instances of research are classified according to five dimensions: domain, phenomenon/task, intervention, method and theory/concepts. A small study was conducted to explore the utility of the proposed taxonomy using a data set of 55 journal papers and three different coders. This study generated preliminary support for the general utility of a multi-dimensional taxonomy for HF/E and for the specific utility of the proposed dimensions. Most importantly, this study identified difficulties associated with the development and application of such a taxonomy to inform future development and evaluation efforts.
Does the Jerome H. Ely Human Factors Article Award Predict Scientific Impact BIBAFull-Text 935-938
  John D. Lee; Anna Shearer; Andrea Cassano; Kim J. Vicente
Does the "Jerome H. Ely Human Factors Article Award" predict scientific impact? We answered this question by investigating whether the 13 award winning papers published in Human Factors between 1987 and 2000 were cited much more frequently than the 730 non-award winning papers published during the same period. The results showed the award significantly increases the citation rate of articles, but accounts for only 0.2% to 1.3% of the variance in the citation rate. Author productivity accounts for far more variance in the authors' total citation rate (65.0%) and in the citation rate of the authors' most cited article (12.0%) than does award receipt. These results have practical implications for the objective recognition of scientific impact by professional societies and for the choice of research topics, particularly by graduate students.

GENERAL SESSION: General Sessions Posters

Contributors to Human Errors and Breaches in National Security Applications BIBAFull-Text 939-942
  Daniel J. Pond; F. Kay Houghton; Walter E. Gilmore
Los Alamos National Laboratory has recognized that security infractions are often the consequence of various types of human errors (e.g., mistakes, lapses, slips) and/or breaches (i.e., deliberate deviations from policies or required procedures with no intention to bring about an adverse security consequence) and therefore has established an error reduction program based in part on the techniques used to mitigate hazard and accident potentials. One cornerstone of this program, definition of the situational and personal factors that increase the likelihood of employee errors and breaches, is detailed here. This information can be used retrospectively (as in accident investigations) to support and guide inquiries into security incidents or prospectively (as in hazard assessments) to guide efforts to reduce the likelihood of error/incident occurrence. Both approaches provide the foundation for targeted interventions to reduce the influence of these factors and for the formation of subsequent "lessons learned." Overall security is enhanced not only by reducing the inadvertent releases of classified information but also by reducing the security and safeguards resources devoted to them, thereby allowing these resources to be concentrated on acts of malevolence.
On Informing Women of Child Bearing Age about Seat Belt Risk during Pregnancy BIBAFull-Text 943-946
  Kenya Freeman; Michael S. Wogalter
Seat belts have been effective in reducing serious injuries and deaths in vehicular accidents. However, their use by women in the third trimester of pregnancy can cause placental damage and fetal injury or death in relatively minor motor vehicle accidents without severely injuring pregnant women. The lack of seat belt use in similar or more serious accidents could cause severe injuries or death to pregnant women from impacts within the cabin or from ejection, and in turn could lead to fetal injuries or deaths. The present study sought to determine whether women between the ages of 16 and 45 (child bearing age) would like to be informed of these risks. Ninety-nine of the 101 women surveyed indicated they would like to be informed of the risks, and that they would expect to find this information in the vehicle's owners manual. In dealing with the risks, some women indicated that they would wear the seatbelts and others indicated they would not. Most respondents indicated that they would reduce the risks by reducing their use of the vehicle during pregnancy. These results have implications for risk communications.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences and Cognition [Lecture]

Perceptions of Sport-Utility Vehicle (SUV) Safety by SUV Drivers and Non-Drivers BIBAFull-Text 947
  Michael S. Wogalter; Vincent C. Conzola; Eric F. Shaver
The number of sport-utility vehicles (SUVs) on U.S. roads has grown substantially in recent years. Despite the common perception of being safer than automobiles, SUVs are more likely to be involved in rollover accidents than other vehicles. Other negative aspects include increased headlight glare "blinding" passenger car drivers due to SUV's higher ground clearance, greater difficulty for other drivers seeing around SUVs because of their size, and poor gas mileage. Despite the negative publicity surrounding SUVs, the unfavorable aspects are apparently being downplayed to some degree because these vehicles have become a popular choice with consumers. It may be that SUV drivers tend to overlook the problems or they are willing to forgive the shortcomings of SUVs in light of other benefits (e.g., greater passenger and cargo space, style, etc.). The present study examined SUV drivers and non-drivers perception ratings of five SUV negatives: (a) seeing above or around them, (b) involvement in collisions with smaller vehicles with less mass, (c) headlights "blinding" the eyes of motorists in front of them in smaller vehicles, (d) rollover accidents, and (e) low gas mileage. Participants rated how much of a problem each was by using a 9-point Likert-type scale with the following verbal anchors tied to the even-numbered ratings: (0) "not a problem at all," (2) "somewhat a problem," (4) "a problem," (6) "very much a problem," and (8) "extremely a problem."
Decision-Making Styles Associated With Accidents: Defining the High Risk Pilot BIBAFull-Text 948-952
  Richard J. Adams; Booz Allen Hamilton; Jefferson M. Koonce; Peter V. Hwoschinsky
This study involved an extensive experimental survey of 4000 pilots. It was designed to determine decision-making variables that could be used to identify high risk taking pilots who have had an accident (cases) vs. low risk pilots who have been accident free (controls). The information data set collected with this survey instrument provided a rich core of knowledge that has not been analyzed before as a whole. The ultimate goal was to use this core of information to develop a global index related to a pilot's propensity for accidents.
   The analyses included: validating the risk taking hypotheses, the development of a discriminant functions to determine if cases and controls could be correctly classified using the instrument, and the development of a risk taking characteristic model. It was found that 80.1% of the cases and controls could be correctly classified using the entire 122 question set. If a simplified five question set was used, 68.2% of the cases and controls could be correctly classified.
Assessing Individual Differences in Decision Making Styles: Analytical Vs. Intuitive BIBAFull-Text 953-957
  Thomas E. Nygren; Rebecca J. White
Decision strategies are often characterized as being intuition-based or analytically-based. The use of these strategies is proposed to be associated with individual differences in propensity toward using different decision making styles. A reliable self-report measure, the Decision Making Styles Inventory (DMI), consisting of 15 items on each of three scales was constructed. The items were found to differentiate among an "analytical", an "intuitive", and a "regret-based" emotional decision making style. The analytical and intuitive scales were found to predict differences in performance in a complex dynamic decision making task. On a decision making subtask, a greater general reliance on an analytical decision making style was found to lead to poorer performance. Greater reliance on a more intuitive approach had no effect on this subtask, but was found to predict better performance as workload levels increased. These findings suggest that human performance may be significantly influenced when either a more intuitive or analytical decision style is used. Implications for training the adaptive decision maker are discussed.
The Effects Of Prior Knowledge On Goal Variability Learning:The more goals the Merrier BIBAFull-Text 958-962
  Jeffrey T. Hansberger; Robert W. Holt
Prior knowledge and experience influence many of our everyday task interactions and knowledge acquisition. One way this happens is by goal choice and goal-oriented behavior. This study focused on the effects of goal variability with repeated interactions with a complex, dynamic task over several months. The effect of goal variability on knowledge acquisition mechanisms and learning of task domain knowledge was observed through the use of the microgenetic approach. Prior knowledge had strong implications for the profile of active goals, interactions with the task and ultimately, learning. Goal variability influenced the use of specific knowledge-acquisition mechanisms. By the final session, goal variability, regardless of the content of the goals, heavily influenced increments in domain knowledge. Variability may have beneficial effects when applied to goal selection, knowledge-acquisition mechanisms, task strategies, and learning over time. Implications of this study may extend to training and other learning and teaching environments.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences Potpourri [Lecture]

Personality, Coping and Task-Induced Stress in Customer Service Personnel BIBAFull-Text 963-967
  Gerald Matthews; Shona Falconer
This study investigated predictors of stress responses in customer service personnel working for a major telecommunications company. 91 participants performed a simulation of their work task. They were presented with telephone inquiries, and tested for their knowledge of the correct response. Several findings of a previous study (Matthews & Falconer, 2000) were replicated. Performing the task appeared to be intrinsically stressful, as evidenced by a large magnitude increase in subjective distress. Individual differences in stress state were related to strategy for coping with task demands. The 'Big Five' personality traits were compared with measures of dispositional coping style as predictors of subjective stress state. Coping measures added significantly to the variance in stress state explained by the Big Five. Emotion-focused strategies such as self-criticism appeared to be especially damaging in the customer service context. Coping measures might be used by organizations to select operators likely to be resistant to task-induced stress.
Computerized Workplace Fitness Assessment: Sensitivity Vs Specificity BIBAFull-Text 968-972
  Robert S. Kennedy; Janet von Sternberg; Robert C. Kennedy
Computerized fitness tests are used in workplace settings to measure for impairment resulting from factors such as environmental fatigue, toxic chemicals, environmental stresses, sleep disorders, high workload, illness, emotional upset, and others. One obstacle in implementing these instruments has been resistance from organizations due to concerns with accuracy of the tests and how the scores apply to the tasks in the workplace. Organizations are also often reluctant to adopt this type of instrument due to the potential for false positives in impaired performance. In order to develop a scoring method which addresses these issues by achieving substantial Specificity (>97%), while maintaining high Sensitivity, we employed computerized fitness tests to evaluate subjects with graded alcohol doses. By implementing Multiple Regression and Multiple Cutoff Analyses, we were able to achieve the desired levels of Specificity, while maintaining high Sensitivity.
Task Context and Individual Difference Effects on Skill Acquisition of Visual Processing Strategy BIBAFull-Text 973-977
  Elizabeth Kramer; James H. Pratt; Young Woo Sohn
Pratt and Sohn (2001) suggested that training context impacts those with a holistic strategy while training context does not influence transfer performance for those with an analytic strategy. The present research attempts to compliment and extend their findings by examining the role of complexity and how it interacts with individual differences in visual processing strategy. Participants were given a visual discrimination task in which they trained on one of four stimulus sets that varied in complexity and similarity and then transferred to novel stimuli. Stimulus complexity was defined by the number of points each stimulus had. Stimulus similarity was defined by the six levels of discrimination difficulty. Using methods described by Pratt & Sohn (2001), participant's individual processing strategy was extracted from a screening session prior to training. Participants were categorized as either "analytic" or "holistic" based on their response reaction time as a function of stimulus complexity. Those with an analytic strategy performed with greater accuracy in transfer as complexity level decreased; those with a holistic strategy performed with greater accuracy in transfer as complexity level increased. Graphical design and training techniques are discussed.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Performance Posters

Hedonomics Affective Human Factors Design BIBAFull-Text 978-982
  Martin G. Helander
People have affective reactions towards tasks, artifacts and interfaces. Theses reactions are caused by design features, which operate either through their perceptual attributes or from a sense of control in handling or from past experience. A systematic framework is proposed to conceptualize Affective Human Factors Design or as we call it -- Hedonomics. The word Hedonomics is derived from the Greek "hedone" (pleasure -- akin to sweet) and "nomos" (laws, principles). The focus is on pleasurable design of artifacts and tasks. Several existing theories may combine to support this framework, including: Human Information Processing, Activity Theory, and Theory of Flow. There are also analogies with past theories -- in human need structure, motivation, job satisfaction, and stress research. The problem is now to conceptualize Hedonomics, to propose theories that can be used for design, and appropriate measurement tools. It is particularly important to develop tools to measure and predict affective design -- and on an individual level predict user and customer needs for affect.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences Potpourri [Lecture]

A Framework for Affective Customer Needs in Product Design BIBAFull-Text 983-987
  Halimahtun M. Khalid
A systematic framework is proposed to conceptualize affective customer needs in product design. Customer needs were derived for current and future electronic devices in automobiles. Subjects rated their preferences for fifteen product attributes on 10-point semantic differential scales. Using factor analysis, three generic factors were extracted namely: holistic attributes, styling, and functional design. Depending upon the familiarity of the device there were clear differences among potential customers. Unknown devices such as navigation map were assessed first hand by using holistic attributes. Familiar design such as car radio and cell phone were assessed using styling and functionality attributes. Customer reactions and preferences may be caused by product design parameters that operate either through their perceptual attributes or from the experience they acquire in using the artifacts or interfaces. Functional (or cognitive) customer needs can be derived top-down using product design features. Affective customer needs are difficult to derive top-down -- typically they are evaluated by looking at several design propositions.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Performance Posters

Relating Goal Orientation to the Acquisition of a Complex Skill: Does the Context Matter BIBAFull-Text 988-992
  Eric Anthony Day; Charlene Stokes; Erich C. Fein
The extant literature on goal orientation is primarily focused on scholastic and athletic achievement. This study extends the literature by examining the viability of three goal orientation dimensions (learning, performance-approach, and performance-avoid) as predictors of complex skill acquisition. Ninety-eight males participated in 7 hours of training in order to learn a computer-based task that simulated the demands of a dynamic aviation environment. Participants completed paper-and-pencil measures of global and task-specific goal orientation as well as a test of general cognitive ability (g). Training outcomes included declarative knowledge, knowledge structure accuracy, skill acquisition, skill retention, and skill transfer. The results indicated that both performance-approach and performance-avoid orientations explained unique variance in training outcomes beyond that explained by g. However, both performance orientations were related to the training outcomes only when operationalized as task-specific orientations, not when operationalized as global dispositions. Learning orientation was not significantly related to the training outcomes.
Profiling Users of a Unified Communication Service: Understanding Communication Traits and Styles BIBAFull-Text 993-997
  Leonardo Ruppenthal; Mark Chignell
In spite of the powerful functionality and message integration offered, unified communication (UC) has yet to be widely adopted as a solution that meets the demands and complexities of modern communicators. By understanding individual differences, requirements, and preferences, it should be possible to design better communication interfaces and services. This study examined the characteristics of communication-related preferences among users of a three-month UC trial. Survey data from 123 respondents were analyzed. A series of factor analyses identified 19 communication traits, 7 of which were particularly interesting. A cluster analysis suggested three types of communication styles: Low-tech, Power, and Strategic. Future research will attempt to relate the current findings to actual communication behaviour. The creation of a communication preference inventory (CPI) is also discussed.
Assessing Individual Differences In Spatial Strategies BIBAFull-Text 998-1001
  Valerie K. Sims; Hana S. Smith
This research examined the strategies, emotions, and beliefs described by participants completing a complex three dimensional spatial task. After completing the task, participants examined a video of themselves performing the task. During the video performance, participants completed a thought listing exercise designed to elicit strategies used, as well participants' beliefs about their own adequacy and the degree of difficulty of the task. These data were coded by two independent observers. Strategies, beliefs, and emotions reported were predicted both by the sex of the participant and the success at the task. Unsuccessful males and females did not differ from one another in their reported strategies, beliefs, or emotions. However, successful males reported many more specific strategies, whereas successful females reported greater emotional regulation. Additionally, trial and error was identified by successful females as their main strategy. Guidelines for eliciting spatial strategies follow.
Individual Differences in the Stress and Workload of Sustained Attention BIBAFull-Text 1002-1006
  James L. Szalma
The effects of individual differences in dispositional pessimism and optimism, and choice of coping strategy, on performance, stress, and workload in vigilance tasks were investigated. Prior research indicated that pessimistic observers performed more poorly and experienced higher levels of stress than optimists. In addition, coping strategies employed by observers have been linked to the stress and workload associated with a variety of tasks. To date, no one has examined the relations among these variables in regard to vigilance within one study. Pessimism and optimism were found to be unrelated to performance, but predictive of both pre- and post-task stress and choice of coping strategy. There was also evidence that the influence of personality on post-task stress and choice of coping strategy may be mediated by pre-task state. Personality and coping strategies also influenced perceived workload.

INDUSTRIAL ERGONOMICS: Ergonomic Risk Exposure Assessment [Lecture]

Validation and Field Testing of an Ergonomic Computer Use Checklist and Guidebook BIBAFull-Text 1007-1011
  Ira Janowitz; Arlie Stern; Don Morelli; Eileen Vollowitz; Mark Hudes; David Rempel
The authors developed a validated office ergonomics checklist that focused on outcomes instead of workstation features. The workstation is evaluated primarily through observed working postures and movement patterns while the subject performs their usual tasks. A guidebook for the improvement of computer workstations is keyed to the checklist, to lead the user in reducing risk factors and improving workstation ergonomics. The checklist was first validated in a field test with three expert evaluators. The checklist and guidebook were later tested with a large employer and used as a self-evaluation instrument, by a co-worker, and by an Ergonomics Coordinator with training and experience. Workstations were evaluated by an independent ergonomist before and after interventions were made. Results indicated that the checklist and guidebook were effective in making significant improvements in workstation conditions when administered by an Ergonomics Coordinator, but not when used as a self-assessment or by an untrained co-worker.
Ergonomic Antecedents and Disabling Construction Injuries BIBAFull-Text 1012-1016
  Theodore K. Courtney; Simon Matz; Barbara S. Webster
The US construction industry comprises 5.4% of annual US employment but accounts for 7.8% of non-fatal occupational injuries. Little is known about construction injury disability and the contribution of ergonomics-related antecedents. The construction experience (n = 35,790) of a national worker's compensation insurer was analyzed. Disability duration (LOD) was calculated from indemnity payments data. Contributions of ergonomics-related antecedents to the most costly injuries were identified. The most frequent injuries were low back pain (15%), foreign body eye injuries (8.5%), and finger lacerations (4.8%). Back pain also accounted for the greatest percentage of costs (21.3%) and disability days (24.5%). The average LOD for an injured construction worker was 50 days (median= 7 days). Among the 5 most costly injuries, wrist fractures had the longest LOD (mean= 247, median= 38). Ergonomics-related antecedents were typically cited as the injury causing event in 4 of the 5 most costly injuries.
Physical Exposure Assessment in a Large Prospective Upper Extremity Musculoskeletal Disorders Study BIBAFull-Text 1017-1021
  Stephen Bao; Peregrin Spielholz; Ninica Howard; Barbara Silverstein; Caroline Smith; Ruby Irving; Cindy Orr; Ben Hamilton; Maureen Pilon; Carolyn Salazar
This paper describes a battery of physical exposure assessment methods used in a large prospective upper extremity musculoskeletal disorders study. Different from some previous prospective studies, this study collects health and physical exposure data for each study subject rather than at a group level. Subjects are recruited from different job categories based on their hand activity exposure categories. Multiple exposure assessment methods are used to measure job physical exposures such as force, repetition, and work posture. This will allow us to compare the sensitivity of different exposure assessment methods in predicting the risk for upper extremity musculoskeletal disorders. Procedures have also been taken to monitor inter-observer reliability for some observational analyses. During the first year of the study, baseline exposure measurements have been collected from 607 volunteers at 11 different worksites. Follow-up measurements have also been collected in these worksites. Whenever a participant has a significant job change, a new exposure assessment is conducted at the new job. This paper will primarily discuss the various exposure assessment methods used in this study, and use some preliminary results to demonstrate some of the data reduction methods.
A Methodology for Incorporating Ergonomics into Manufacturing Systems Design BIBAFull-Text 1022-1026
  Victor Paquet; Li Lin
Approaches to manufacturing systems design often utilize a sequential procedure that focuses on the use of new and available technologies to improve production capacity, with the roles of employees in production processes considered much later. This study developed a methodology that integrates both manual and computer simulations to evaluate system performance and identify ergonomic problems early in the system design process. Information about operator performance and potential ergonomic risk factors is obtained through manual simulations, and estimates of operator utilization and system throughput are obtained through computer simulations. An iterative design process is used, with the results of manual and computer simulations informing each other during subsequent simulations. The results of an industrial case study in which the methods were applied to the design of a manufacturing cell demonstrate that the methodology can be used to design manufacturing systems with significant savings in labor cost and improved manufacturing system flexibility.
Combining Models to Solve the Problem: Macroergonomics and Public Health BIBAFull-Text 1027-1031
  Valerie J. Berg Rice; Mary Z. Mays
Macroergonomic and Public Health approaches were combined with typical ergonomic injury prevention approaches. This combination permitted a thorough investigation of all systems and personnel that might impact on musculoskeletal injuries among U.S. Army students attending Advanced Individual Training as a Combat Medic. The results allowed for an evaluation of the process, the attitudes and beliefs of the cadre (supervisors), and permitted development of a more harmonized, holistic injury prevention program. The results demonstrated success in terms of positive attitudes toward the program, an overall 10.8% reduction in clinic visits for musculoskeletal complaints, a 37% decrease in limited duty days, and a 60% decrease in sprain and strain injuries. A targeted prevention program yielded 36% fewer clinic visits and a 50% reduction in limited duty days. The high level of success achieved by this program was in large part due to the combined processes employed to lay a sound foundation for assessment, design, and evaluation of occupationally based musculoskeletal injuries.
Methodological Approaches to Research and Musculoskeletal Complaints and Injuries Panel BIBAFull-Text 1032-1036
  Krystyna Gielo-Perczak; Waldemar Karwowski; Shrawan Kumar; William Marras
An important aspect of workplace design is the creation of possible ways to bring innovations to the prevention of excessive joint loading. The solutions for finding these different options are new theoretical concepts with applications of biomechanics and fuzzy logic, innovative insights into the human body using simulation tools, critical examinations of the relationship between workplace analysis and causality in the control of musculoskeletal disorders, and inventive studies of their validity through epidemiology. These methodological approaches can be useful tools for minimizing incompatibilities between the capabilities of workers and the demands of their jobs and prevention of likely musculoskeletal injuries during work. The results of these approaches can assess the suitability of the designed human-machine system and determine possible improvements in the workplace.

INDUSTRIAL ERGONOMICS: Upper Extremity Research I [Lecture]

Inter-Rater Reliability for Hand Activity Level (HAL) and Force Metrics BIBAFull-Text 1037-1040
  Marissa L. Ebersole; Thomas J. Armstrong
Observational rating methods are used frequently in ergonomic job analysis because they are less costly and time consuming than other methods. The ACGIH recently published a threshold limit value (TLV) for repetitive work. This TLV suggests the use of one such observational method developed by Latko et al. (1997) for rating Hand Activity Level (HAL) and peak force. One criticism of Latko's method is the unknown reliability and consistency of the raters during the analysis process. Latko suggests the use of two or more trained observers to increase this consistency. This study analyzed 410 jobs at an automotive assembly plant using 2 observers recording initial and final ratings. A weighted kappa was calculated for the HAL and peak force before and after discussion. Before discussion, HAL reliability was rated as moderate and peak force as fair. After discussion, both HAL and peak force kappa values were rated as good.
Wrist and Forearm Postures and Velocities in Repetitive Precision Tasks BIBAFull-Text 1041-1045
  Kathleen Shyhalla; Victor Paquet; Colin Drury
Precision work has been shown to impose physical demands over and above similar work that does not require precision, but few studies have evaluated the effects of such work on the musculoskeletal stress of the upper extremities. Repetitive tasks that involved moving between a Home disk and a precision target were studied. The movements from the Home to the target were divided into a ballistic phase, followed by a slower homing-in phase. Work in two layouts, with the target in front of, or to the side of the Home disk, and three levels of precision were investigated for each phase of the home-to-target movement. Wrist and forearm postures and joint velocities were significantly different (P < 0.05) during the ballistic and homing in phases of travel for 21 of the 24 indices considered. Postures changed rapidly during the ballistic, but were sustained during the homing-in phase. Work in the forward versus side layouts produced statistically different joint angles and velocities (P < 0.05) for 17 of the 24 indices considered. Different levels of task precision elicited statistically differences in 5 of the 12 joint velocities (P < 0.05).
   Interactions were also important. The phase of movement factor produced statistically significant interactions with layouts (P < 0.05) for 11 of 12 postures and 5 of 12 velocities, and with levels of precision (P < 0.05) for 5 of 12 velocities. With such important interaction effects, it is clear that breaking repetitive precision tasks into distinct phases promotes a better understanding of how precision work affects the musculoskeletal stress of the upper extremities. Graphical representations also show differences in how joint velocities were impacted by levels of precision for the forward and side layouts.
Upperlimb EMG and Discomfort for Forearm Torques Combined with Horizontal Forces BIBAFull-Text 1046-1050
  Leonard W. O'Sullivan; Timothy J. Gallwey
The first part of the study examined maximum forearm torque in both the supination and pronation directions at three forearm joint rotation angles. EMG data were also collected during the maximal exertions. The second part of the study involved subjects exerting intermittent isometric torques at 10% and 20% of MVC in both torque directions, at three forearm angles. These conditions were each tested while simultaneously applying a pushing, pulling and no pushing or pulling horizontal force. The results show that supination torque was strongest and that maximum torque in both directions were significantly affected by forearm joint angle. Very high levels of muscular activity in the forearm flexors and extensors during the exertions point to a direct link between the torques and injury. Discomfort scores from the intermittent exercises revealed significant main effects for force level, forearm angle and the application of a horizontal force simultaneous to applying torques, while direction of torque was only significant in interactions.
Determination of Optimal Handle Sizes by Use of Normalized Hand Sizes in a Pulling Task BIBAFull-Text 1051-1055
  Yong-Ku Kong; Andris Freivalds
Two handle shapes (double frustum and oval) with different sizes, resulting in a total of 10 handles were tested to determine optimal handle sizes in a pulling task. Force data were collected by force sensitive resistors (FSR), which were placed on the palmar surface of the fingers. Subjective ratings of discomfort were also recorded for each handle. The results of subjective ratings showed that medium sized-handles were described as being more comfortable than the other sizes, and double frustum handles required less finger forces than oval handles. 'Normalized Hand Size (NHS)', which is the ratio of handle circumference to user's hand length was applied to predict the optimum handle size for the subjective ratings as well as finger forces in a pulling task according to the user's hand size. In oval handles, generally medium handles showed higher preference and required less finger forces than large handles. In case of the double frustum handles, the 60.9% NHS was the best ratio for the least subjective discomfort ratings and the 58.1% NHS was recommendable for the least finger force requiring in a pulling task. Based on the results of NHS study, 34.4~38.1 mm and 31.4~35.0 mm were recommended for middle hand size groups of male and female, respectively. The optimum handle sizes for the males were about 8.1~8.7% larger than that of the female.
The Effects of Dynamic Wrist Workloads on Nerve Conduction Measures for Evaluating Carpal Tunnel Syndrome BIBAFull-Text 1056-1060
  Hyunkook Jang; Andris Freivalds
The effects of exposure to three hours of forceful exertion and repetitive movement on nerve conduction function were examined in fifteen subjects. Wrist workload was recorded by using biaxial electrogoniometer and force resistance sensor, while the nerve conduction measures were recorded with TECA TD-20 EMG machine. The results of peak latency showed an overall increase during task performance for high force-low repetition, low force-high repetition, and low force-low repetition conditions, while little change for high force-high repetition condition. Analysis of variance on peak latency detected significant effect on time (p<0.001, F=13.79). For amplitude, overall increases for all workload conditions were found until 60 minutes into task performance, but after that time, amplitudes stayed relatively level. As expected, skin temperature had highly significant correlation with peak latency (p<0.001, r2 =0.736), where peak latency appeared to increase as skin temperature decreased. These same results were found for peak latency and amplitude after skin temperature corrections. Correlation analyses indicated that the maximum wrist flexion, maximum range of motion and cumulative exposure time had highly significant relationships with peak latency and temperature-corrected peak latency over time. Specifically, the cumulative exposure time of F/E angle > 30° may serve as the best predictive measure for investigating the effects of dynamic wrist workloads on the nerve conduction.

INDUSTRIAL ERGONOMICS: Trunk/Torso I [Lecture]

The Effect of a Variable Lumbar Erector Spinae Sagittal Plane Moment Arm on Predicted Spinal Loading BIBAFull-Text 1061-1065
  Michael J. Jorgensen; William S. Marras; Thomas R. Waters
Recent research indicates that the sagittal plane moment arm of the erector spinae decreases at the L5/S1 level during torso flexion. The objective of this study was to assess the predicted L5/S1 spinal loading from a lifting task when allowing the erector spinae sagittal plane moment arm to vary during torso flexion. Nineteen male subjects lifted three loads from two origin locations to an upright neutral posture. Spinal loading was predicted from an EMG-assisted biomechanical model that allowed the erector spinae moment arm to vary during torso flexion. The predicted lateral, anteriorposterior shear and compression forces increased by 7.4%, 11.1% and 6.6%, respectively, when compared to using a biomechanical model that kept the erector spinae moment arm constant. These results suggest that models that account for the varying erector spinae moment arm predict greater spinal loads, especially for motions that involve a large degree of torso flexion.
Relative Contribution of Workplace Factors and Individual Characteristics in the Development of Spine Loads BIBAFull-Text 1066-1070
  K. G. Davis; W. S. Marras; T. R. Waters
Thirty males and thirty females performed lifting tasks while being exposed to varying levels of physical (box weight, task asymmetry), psychosocial (social support and mental concentration), and combination (lift rate, box placement) workplace factors. The study investigated the impact of these variables as well as individual factors (gender, personality) on trunk kinematics and kinetics, muscle activity, and the three-dimensional spinal loads. The study results indicate box weight, placement control, individual's anthropometry, and to a lesser extent gender and personality directly impact the loads on the spine as well as the trunk kinematics, kinetics, and muscle activity. Both the physical and mental aspects of the workplace must then be considered when developing ergonomic interventions.
Effects of Load and Posture on the Recruitment of Trunk Muscles BIBAFull-Text 1071-1075
  Sean Gallagher; William S. Marras; Kermit G. Davis
Seven male subjects performed 8 cable lifting and hanging tasks, while trunk kinematics and electromyographic data often trunk muscles were obtained. The objectives of the study were to evaluate trunk muscle recruitment and spine loads resulting from performance of this task in different postures and with different load magnitudes. The eight tasks were combinations of four postures (standing, stooping, kneeling on one knee or both knees) and two levels of load (0 N or 100 N load added to existing cable weight). Results indicated that changes in posture and changes in load magnitude both affected muscle co-activation; however, the influence of these variables were quite different in nature. Increased load magnitude resulted in a generalized increase in the co-activation of all trunk muscles, no matter which posture was employed (p < 0.05). Changes in posture significantly affected trunk muscle recruitment patterns (p < 0.05); however, the posture effect typically involved a relatively small subset of trunk muscles. No significant interactions were detected (p > 0.05), indicating that posture and load effects are both independent and additive.
Nonlinear System Identification Applied to the Biomechanical Response of the Human Trunk During Sudden Loading BIBAFull-Text 1076-1080
  Brad M. Lawrence; Gregory D. Buckner; Gary A. Mirka
Epidemiological and biomechanical studies have indicated that sudden loading of the trunk may be a risk factor for low back pain development. Sudden loads may contribute significantly to the development of low back pain, due to the large muscular force responses associated with these loads. To date, most sudden loading studies have been observational studies that provide rich informational content, but do not provide a solid theoretical model to investigate kinematic and kinetic responses. A novel approach using nonlinear system identification and a time-varying model is introduced in this study to investigate the underlying dynamics of the trunk biomechanical system during sudden loading. This model has been used to study the effects of warning signals, muscular fatigue, and training on the biomechanical response of one subject. Data from this subject and additional subjects may provide recommendations for training protocols and administrative and engineering interventions that minimize exposure to potentially hazardous sudden loads.

INDUSTRIAL ERGONOMICS: Fatigue Research [Lecture]

The Effects of Differing Overhead Heights on Shoulder Fatigue During a Repetitive Intermittent Task BIBAFull-Text 1081-1085
  Deepti Sood; Kristopher Hager; Maury A. Nussbaum
The purpose of this study was to determine the effect of different overhead work heights on shoulder fatigue. Ten participants (6 males, 4 females) with manual work experience were recruited to perform a dynamic intermittent overhead task simulating automotive assembly work. Participants performed a keyboard tapping task using a hand tool at three different heights, relatively to individual anthropometry, for up to one hour. Throughout the trials, electromyography (EMG) was recorded from three shoulder muscles (anterior deltoid, middle deltoid, and trapezius), and subjective ratings of perceived discomfort (RPD) were obtained. Key striking accuracy was used as a measure of task performance. Though results were not always statistically significant, the EMG, RPD, and performance measures all indicated that higher working heights generally lead to more rapid onset of fatigue.
EMG Changes of the ECU Muscle with Exposure to Repetitive Ulnar Deviation BIBAFull-Text 1086-1089
  Kirsty J. Bennie; Vincent M. Ciriello; Peter W. Johnson; Jack Tigh Dennerlein
Our objective was to quantify changes in muscle EMG activity due to repetitive work. Using a repeated measures design, 13 females participated in 3 conditions, each lasting two eight-hour days: a control inactive condition, and two repetitive work conditions with ulnar deviation tasks at 20 and 25 repetitions per minute. EMG of the extensor carpi ulnaris muscle (ECU) was recorded during voluntary isometric contractions (20% and 60% MVC) eight times throughout the work and control days. The amplitude of the EMG signal was lower on workdays compared to the control days. Initial median frequency of the EMG signal showed no change between the control and workdays; however, the decline of the median frequency with respect to time over the course of each isometric contraction was steeper during workdays compared to control days. These changes suggest that the muscles are in an early stage of fatigue when working for an eight-hour workday.
Identification of Measures Sensitive to Fatigue Development Associated with Low-Level Exertions of the Neck Musculature and the Effects of Age BIBAFull-Text 1090-1094
  Sharon Joines; Carolyn M. Sommerich; Gary Mirka; James R. Wilson; Samuel Moon
This research had two purposes: to identify measures sensitive to fatigue development associated with low force, static exertions and to investigate the effects of aging on fatigue onset associated with low-level exertions of the neck musculature.
   Fourteen subjects participated ranging in age from 20 to 62 years. The task consisted of a submaximal neck extension exertion held until fatigue. Based on the results of this experiment, it was found that:
  • Several measures are sensitive to fatigue induced during a low-level static
       exertion of the neck extensor muscles, including: discomfort, three EMG time
       domain and four frequency domain parameters
  • when comparing groups based on age, results and interpretations of effects
       due to age may be directly be influenced by the choice of dependent measure
       (such as discomfort, maximum force, and potentially time to fatigue);
  • regardless of age, some subjects may exhibit fatigue resistance at low
       exertions levels.
  • Indices of Muscle Fatigue BIBAFull-Text 1095-1099
      Shrawan Kumar; Tyler Amell; Yogesh Narayan; Narsimah Prasad
    The objective of the study was to determine if any of the many indicators of localized muscle fatigue (LMF) mirrors the decline in force more closely (gold standard). If not, can a group of indicators can predict LMF better? Nine normal young subjects were required to exert their maximal voluntary contraction (MVC) and 40% of MVC in elbow flexion as long as they could. The magnitude of the force, EMG amplitude, median frequency (MF), muscle bed blood volume, and muscle oxygenation were measured for MVC. For the 40% MVC contraction in addition to the foregoing variables oxygen uptake (VO2), ventilation volume and heart rate were also measured. The rate of perceived exertion (RPE), visual analog score (VAS) and body part discomfort rating (BPDR) were measured for both contractions. Data were subjected to the analysis of variance (ANOVA) with repeated measures, correlation and regression analysis. Different percentiles of the tasks were significantly different in both contractions (p<0.001). The MF was the strongest indicator of the force decline in MVC (r = 0.91; p<0.001) but in 40% MVC the VAS was a better indicated. None of the variables consistently represented LMF in different levels of contraction. A different grouping of objective and subjective measures for MVC and 40% MVC increased the predictability of the force decline (LMF).

    INDUSTRIAL ERGONOMICS: Physical and Mental Workplace Factors [Lecture]

    Interactive Effects of Physical and Mental Workload on Subjective Workload Assessment BIBAFull-Text 1100-1104
      Angela Astin; Maury A. Nussbaum
    Relatively little research has investigated subjective workload assessment during tasks involving both physical and mental demands. Development of more comprehensive workload assessment tools depends on understanding the effects of physical and mental activity on an individual's perception of workload. This study investigated the interaction between the two types of demands and the potential effects of such interactions on subjective workload assessment and performance. Common subjective workload assessment tools (Borg CR-10 Scale, Visual Analog Scale, NASA Task Load Index) were used to record changes in perceived workload during varying levels of physical and mental demands. Thirteen participants completed all conditions with the results summarized to identify potential trends in the data. The results suggest that a physical demand component did not affect subjective mental workload assessment (p = 0.9916). In addition, the presence of mental demands did not affect physical workload assessment (p = 0.9183). High correlations were found between the subjective mental workload assessment scores and mental performance (r = -0.8 and -0.9).
    The Effect of Personality Type on Assembly Time and Wrist Kinematics During a Laboratory Task BIBAFull-Text 1105-1109
      Naomi F. Glasscock; Gary A. Mirka; Carolyn M. Sommerich; Katherine W. Klein
    Psychosocial factors are becoming increasingly more prevalent in studies that explore occupational musculoskeletal injury/illness. The research presented here explores the relationships between two psychosocial factors (personality type and time stress) and biomechanical indicators of task performance. Twenty-four subjects participated in this laboratory study. Personality type was assessed using the Jenkins Activity Survey. Participants (12 Type A and 12 Type B) performed an assembly task under verbally imposed "no time stress" and "time stress" conditions. Dependent measures included assembly time and wrist motion parameters. Personality type and time stress demonstrated significant effects on mean assembly time. Time stress significantly and consistently impacted the wrist motion parameters while personality type did not. No significant interactions were noted. Psychosocial factors were found to directly impact biomechanical indicators of task performance. This study demonstrates the feasibility of this approach to explore the roles that psychosocial factors may play in musculoskeletal injury.
    Do the Same Factors Affect Use and Non-Use of Safety Equipment BIBAFull-Text 1110-1114
      M. J. Halter; C. G. Drury
    Safety equipment is often specified by human factors engineers/ergonomists, but it is not always used in practice. Thus, safety belts in cars and patient transfer devices in nursing homes are not universally used despite proofs of their effectiveness and (at times) rules governing their usage. This study was performed in several nursing homes and hospitals to determine whether similar reasons were given for Use or Non-Use of patient transfer equipment by nurses. We tested 30 nurses in the first phase to determine typical reasons for Use and Non-Use, followed by testing 47 nurses using rating scales for the reasons given in a second phase. We also measured actual use of patient transfer equipment, which was low at 40%, nurse demographics and reported back pain. The main finding was that different factors were reliably associated with Use versus Non-Use of the equipment. The strongest factor in Use was enforcement of requirements. Speed of operation was the weakest factor in the Non-Use decision. Such dissociation of positive and negative factors is not uncommon in rating scale data.
    Analysis of Per-Item and Per-Lot Paced Visual Inspection for High Target Probability Conditions BIBAFull-Text 1115-1119
      Rajeev M. Sahasrabudhe; Shannon R. Bowling; Mohammad T. Khasawneh; Anand K. Gramopadhye; Brian J. Melloy
    Inspection, a necessary component in manufacturing to ensure process and quality control, has two main components, visual search and decision-making. The human element, while not perfect, cannot be eliminated from the inspection process because of the inherent advantages that a human inspector has to offer. Since some type of pacing is generally incorporated into the manufacturing setting for cost effectiveness, discovering how speed and rigidity affect the accuracy of inspection is essential. Therefore, this study attempts to explore the relationship between time limits imposed on inspectors and the amount of flexibility they have in performing the inspection task.
    Effects of Cued Micro-Breaks on Self-Reported Severity and Recovery of Upper Limb Disorders in Computer Operators BIBAFull-Text 1120-1123
      Michiel P. de Looze; Swenne G. van den Heuvel; Vincent H. Hildebrandt
    Software programs cueing computer workers to apply regular breaks and physical exercises may help in reducing work-related upper limb disorders. The effects of such a program was investigated among 268 computer workers with upper limb disorders, who were randomised into a control group, a group cued to take extra breaks and a group cued to perform exercises during the extra breaks. A comparison between pre- and post-intervention scores on the severity of the complaints showed no significant differences among the three groups. However, data on the self-reported recovery, obtained after the intervention, showed that, as compared to the controls, more subjects in the experimental groups reported recovery (55% vs. 34%) and less reported deterioration (4% vs. 20%). Hence, people who are cued to take extra breaks, perceive more recovery, although the effect on the severity level of the complaint was not detected. No effect was found of the physical exercises.

    INDUSTRIAL ERGONOMICS: Upper Extremity Research II [Lecture]

    A Survey of Desktop and Notebook Computer Use by Professionals BIBAFull-Text 1124-1128
      Carolyn M. Sommerich
    Over the last quarter century, extensive research concerning work-related musculoskeletal discomfort has been conducted in the area of desktop computer (DPC) use, among professionals and clerical workers. Notebook style computers (NPC) are increasing in popularity and use, often replacing DPCs, yet limited information is available on workers' experience with NPCs. Results are presented from a survey that explored work-related use of desktop and notebook computers by professionals (n=335). Associations were found between musculoskeletal discomfort and work patterns and methods, including work-break patterns, notebook configuration, and notebook transportation mode.
    Wrist and Shoulder Muscle Activity Changes Across Computer Tasks BIBAFull-Text 1129-1132
      Jack Dennerlein; Maria-Helena DiMarino; Ted Becker; Peter Johnson
    The computer workstation is a ubiquitous tool in the office work environment; however, its use varies across many different tasks from surfing the Internet to typing. The question, therefore, is how does exposure to different physical risk factors for musculoskeletal disorders vary across tasks? Fifteen adults (10 females, 5 males) completed tasks simulating work at a computer workstation. The tasks were typing text, completing an html-based form, editing a document, a graphics task, and finally navigating through a series of web pages. During these tasks the muscle activity of the wrist prime movers and three shoulder muscle groups were recorded using surface EMG. For the wrist, the extensors were the most active ranging on average from 8 to 25 percent of Maximum Voluntary Contraction amplitude, with the greatest activity occurring in the typing task. The wrist activity decreased when the work changed from a keyboard-based activity to predominantly mouse-based activity. For the shoulder, the greatest activity was in the Trapezius muscle. The shoulder muscles were most active when both the mouse and the keyboard were required by the task. In summary, wrist and shoulder muscle activities at a computer workstation depend upon the type of task at hand.
    An Analysis of Shoulder Loading Differences for Simulated Industrial Task Performance Between Injured and Non-Injured Subject Populations BIBAFull-Text 1133-1136
      Clark R. Dickerson; Don B. Chaffin
    Detailed characterization of differences in motions between injured and non-injured populations has not been widely studied. These motion differences may have an impact on physical loading of injured populations performing work tasks. This study included analysis of tasks performed by three populations: control, spinal cord injured, and low back pain. Shoulder loading was examined for goal-directed simulated sagittal and lateral plane work tasks through calculation of maximum external dynamic shoulder moments. The significant main effects in determining shoulder moments included: type of task performed (one or two-handed load movement), horizontal distance to target, vertical height of target, and population membership. There was also a significant interaction effect between population and task type. This study establishes that both task requirements and injury status quantitatively effect shoulder loading, particularly for lateral motions, and suggests that ergonomists should consider factors beyond task-defined characteristics when designing job interfaces for injured populations.
    The Relationship between Subjective and Objective Scales on CTS Symptom Severity Using a Self-Administered Questionnaire BIBAFull-Text 1137-1141
      Dongjoon Kong; Andris Freivalds; Milind J. Kothari; Sanjiv H. Naidu
    A group of 39 CTS patients with 60 affected hands participated in the study. A self-administered questionnaire developed by Levine et al. (1993) and nerve conduction measures (NCS) were used. The factor analysis showed a consistent result with previous studies: Primary (numbness, tingling, and nocturnal symptoms) and Secondary (pain, weakness, and clumsiness) symptoms. Peason's correlation coefficients showed that two primary symptoms (numbness and tingling) were highly correlated (p <.05) with NCS results while the other symptoms were not. Among the primary symptoms, only nocturnal symptoms did not show any significant correlation with NCS results. The nocturnal symptoms could be more of a mechanical problem of wrist flexion at night and not a reflection of nerve slowing at night versus daytime but still was a good measure of CTS. The primary symptoms could be used as a potential screening tool for early CTS in the workplace.

    INDUSTRIAL ERGONOMICS: Trunk/Torso II [Lecture]

    The Effects of Distance on Psychophysically Determined Pushing and Pulling Tasks BIBAFull-Text 1142-1146
      Vincent M. Ciriello
    The most frequent and expensive cause category of compensable loss is manual material handling (MMH). In an attempt to minimize these losses, refinement of existing MMH guidelines is a component of redesigning high risk MMH jobs. In the development of our present MMH guidelines (Snook & Ciriello, 1991), maximum acceptable forces (MAFs) of pulling were assumed to respond similarly to pushing at longer distances. The purpose of this experiment was to investigate the effects of 7.6m and 15.2m distances on both initial and sustained MAFs of pushing and pulling at a frequency of 1 min-1. A psychophysical methodology was used whereby the subjects were asked to select a workload without "straining themselves or without becoming unusually tired, weakened, overheated or out of breath." Subjects worked 40 min at each push or pull task within a 4-hour test that included other MMH tasks. The results revealed that initial and sustained MAFs and task time were not significantly different between pushing and pulling at the 7.6m distance. However, at the 15.2m distance, initial MAF of pulling was significantly lower and task time was significantly longer compared to pushing. Sustained MAF was not significantly different at 15.2m. It was concluded that our existing guidelines present an accurate estimate of MAFs at the longer pull distances.
    Application of Principal Components Analysis for Evaluation and Classification of Complex EMG Data BIBAFull-Text 1147-1151
      Miguel A. Perez; Maury Nussbaum
    Many biomechanical models used to produce injury risk estimates for the lower trunk require lower trunk muscle forces as inputs. These forces are typically estimated through the use of surface electromyography (sEMG). The variability inherent in sEMG measurements can, and should, be analyzed to determine the possible presence and sources of excessive variation in the data. Principal components analysis (PCA) provides a robust and straightforward method for performing an analysis of the variability of complex sEMG datasets. This paper describes the results obtained from the application of PCA to a dataset consisting of activation levels for several lower trunk muscles. The results demonstrate the value of the technique in identifying clusters of observations in the data and in simplifying the multidimensional dataset. The use of PCA as a hypothesis generation tool is also explored.
    Use of the Cabs Methodology to Assess Biomechanical Stress in Commercial Crab Fishermen BIBAFull-Text 1152-1156
      Gary A. Mirka; GwanSeob Shin; Kristen Kucera; Dana Loomis
    Commercial fishing is a job characterized by long hours in an unpredictable natural environment and variable demands placed on the musculoskeletal system, requiring strength, coordination, and endurance. The focus of this project was in the quantification of the biomechanical stresses placed on the lumbar spine during the work activities of commercial crab fishermen. The Continuous Assessment of Back Stress (CABS) methodology was used to develop distributions describing the amount of time that each of the three workers on a three-man crabbing crew spend at various levels of spine stress. The results of this analysis, expressed in terms of time weighted histograms, show significant variability in the loading of the lumbar spine during regular daily activities both within and between crew members. While the captain has relatively low stress levels, the mate experiences high force (up to 30kg), dynamic exertions while pulling the crab pots from the water up into the boat and high loads (20-40kg) during the loading and unloading of the boat, while the third man experiences static awkward postures (forward flexed postures held for up to five minutes at a time) as he sorts and packs the crabs.
    Ergonomic Analysis of Pallets and Drum Handling BIBAFull-Text 1157-1161
      Bernard Martin; Diane Adamo; Robert Felicitas; Stephen Burastero; K. Han Kim
    This study investigates the effects of heavy pallet and drum handling on spinal loading at the L5/S1 region and surface electromyographic activity of the erector spinae muscles, and the associated risk of low back disorder (LBD). Ten field technicians at the Lawrence Livermore National Laboratory (LLNL) were asked to unstack plastic and metallic pallets and manipulate 55 gallon waste drums. Lifting the metallic and plastic pallets and lowering a 34 Kg drum induced the highest disc compression at the L5/S1 level, while manipulating the pallets and breaking up a 203 Kg drum induced the highest low back muscle activity. The major results showed that posture has a significant influence on disc compression force; however, the lowest muscle load may not be correlated with the lowest disc compression. The computed disc compression forces and EMG activities are most likely responsible for the elevated risk of back injury in waste management workers.
    Ergonomic Evaluation of California Winegrape Trellis Systems BIBAFull-Text 1162-1166
      Andrew E. Kato; Fadi A. Fathallah
    The winegrape industry suffers from high incidence rates of work related musculoskeletal disorders (MSDs). Pruning of dormant vines requires long periods of highly repetitive and physically demanding work that increases risk for MSDs. The purpose of this study is to quantify risk factors associated with the development of musculoskeletal injuries to the wrist and lower back while pruning five commonly used winegrape trellis systems. Eleven subjects (10 male, 1 female) participated in this study. Subjects performed a simulated pruning task as wrist and trunk postures and psychophysical data were gathered. The results showed significant differences among the trellis systems. Compared to the other systems, the vertical shoot positioned (VSP) was determined to be most optimal in terms of decreasing relative MSD risk. These results will assist vineyards in selecting suitable trellis systems that may improve worker health.

    INDUSTRIAL ERGONOMICS: Ergonomic Movement Research [Lecture]

    A Normative Database of Thumb Circumduction in Vivo: Center of Rotation and Range of Motion BIBAFull-Text 1167-1171
      Peter Braido; Xudong Zhang; Robert Hefner; Mark Redden
    This study aimed to explore the use of a contemporary motion capture system for measuring in vivo maximum thumb circumduction, and through biomechanical modeling and statistical analysis, to establish a normative database of three-dimensional functional thumb range of motion (ROM) and examine the effects of anthropometry and gender. Twenty-eight (14 males and 14 females) anthropometrically diversified subjects performed maximum voluntary thumb circumductions, as the trajectories of surface markers placed on their thumb landmarks were measured by an opto-electronic motion capture system. A globographic representation method determined the best fitting spheres, the center of rotation (COR) expressed in a local coordinate system, and reference axes of thumb circumduction. Thumb ROM was quantified using (1) the cone volume circumscribed by the thumb, and (2) the time-varying included angle with respect to a reference axis, expressed as the joint sinus. Statistical analyses suggest that gender is the most important factor (p < 0.05) in determining the COR while anthropometry has the most significant effect on the cone volume (p < 0.0001), but neither affects the joint sinus measures. The results provide valuable data as well as insights for biomechanical modeling of hand movement, ergonomic design of hand-operated controls or devices, and evaluation of thumb impairments or disorders.
    A Motion Modification Algorithm for Memory-Based Human Motion Simulation BIBAFull-Text 1172-1175
      Woojin Park; Don B. Chaffin; Bernard J. Martin
    Simulating human motions in the virtual CAD world is important in the computerized ergonomic design of products and workplaces. The present study introduces a novel, memory-based approach for simulating realistic human motions and presents a motion modification algorithm. In this novel approach, realistic human motions are simulated by modifying existing motion samples stored in a motion database. The proposed motion modification algorithm was found to be able to simulate human motions accurately. The memory-based motion simulation approach has advantages over existing simulation models as it can simulate qualitatively different types of motions on a single platform, predict motions of different styles, and continually learn new motions.
    The Effect of Challenging Somatosensory Inputs on Eye Movement and Postural Sway Patterns of Workers BIBAFull-Text 1176-1180
      L. Kincl; A. Bhattacharya; P. Succop
    For the construction industry, especially the roofing industry, slips/trips and falls have the highest incident rate leading to an injury and fatality. This study investigated the eye movement and postural sway patterns of industrial workers (n=48) with various work experience (months of work experience on inclined surfaces), fatigue conditions (none, half and full), visual cues (none, H cue), tasks (stationary, reach) and surface inclinations (0°, 14°, 26°). Eye movement variables of length and area of movement as well as fixation data and postural sway variables of area and length were significantly affected (p<0.05) by incline, cue, task and work experience. The effect of the eye movement variables on the postural balance was limited and further study is necessary. The use of visual cues is an effective means of increasing postural stability and could be used in occupational situations where no vertical or horizontal cues are naturally available.
    Effect of Having A-Priori Knowledge of the Floor's Contaminant Condition on the Biomechanics of Slips BIBAFull-Text 1181-1185
      Rakie Cham; Brian Moyer; Mark S. Redfern
    Injuries and deaths are often the result of slips/falls. The perceived danger of slipping affects gait biomechanics. This paper investigated the effect of having a-priori knowledge of the floor's contaminant condition on the biomechanics of slips. Five healthy young male subjects donned a safety harness and walked across a walkway, while ground reaction forces and whole body motion were recorded bilaterally at 60 Hz. Slips on soapy floors occurred under 3 "knowledge" conditions: (1) unexpected slips, (2) slips when uncertain of the contaminant condition, and (3) slips when walking onto known contaminated floors. In (2) and (3), i.e. anticipation of slippery surfaces, subjects generated proactive reactions (reduced stance duration and foot angle at heel contact as well as greater hip flexion) compared to unexpected conditions in (1). Those reactions reduced slip potential but also minimized gait disturbances (reduced slip distance and sliding velocity of the heel) when a slip occurred.
    Relationship between Transitional Acceleration of the Whole Body Center-of-Mass and Friction Demand Characteristic During Gait BIBAFull-Text 1186-1190
      Thurmon E. Lockhart; Jeffrey C. Woldstad; James L. Smith
    A laboratory study was conducted to examine the gait changes associated with aging and the effect of these changes on initiation of slips, initial friction demand, and slip distance utilizing newly defined biomechanical parameters of slips and falls. Twenty-eight subjects from two age groups (young and old) walked around a circular track at a comfortable pace wearing a safety harness. Slippery floor surface was automatically placed on the walking track over force platforms at "unexpected" random time intervals utilizing remote controlled floor changer. Synchronized kinetic and kinematic measures were obtained on both slippery and non-slippery floor surfaces. The results indicated that older subjects step length was significantly shorter, and transitional acceleration of the whole body center-of-mass (COM) was significantly slower than their younger counterparts. Older subjects initial friction demand as measured by required coefficient friction (RCOF) was not significantly different than their younger counterparts. Additionally, older subjects slipped longer and faster than younger subjects. Bivariate correlation analyses suggested that transitional acceleration of the whole body COM was significantly related to friction demand characteristic (e.g., RCOF). These findings suggest that gait changes associated with aging (especially slower transition of the whole body COM) may affect initiation of slip-induced falls among older adults.

    INDUSTRIAL ERGONOMICS: Intervention Ergonomics [Lecture]

    Effects of Glove Use in a Coating Removal Task BIBAFull-Text 1191-1195
      Ian C. Rybczynski; Fadi A. Fathallah
    Workers who are in maintenance and repair occupations are routinely exposed to several musculoskeletal disorder risk factors. The purpose of this study was to investigate the effects of glove use during a coating removal task, which is a common maintenance and repair task. Nine healthy subjects (5 male and 4 female) volunteered to participate in this study. The subjects removed identical painted sections using either a metal finishing (nylon) pad or a plastic scraper, while wearing one of thirteen glove conditions. The order of the glove conditions was randomized for each subject. Force exertions were monitored along with EMG readings from the finger flexors, finger extensors, biceps, and triceps. The results showed that there were significant increases in force outputs and muscle activities when using gloves as compared to a barehanded condition. There was some evidence that indicated glove material and glove thickness are important characteristics in these observations. These findings may have implications for a worker's musculoskeletal disorders risk and for glove selection guidelines in industry.
    The Ergonomics Process in a Large Industry: A Case Study BIBAFull-Text 1196-1200
      Kim M. Rice; Brad Joseph; Helen Kilduff-Rich
    This study reviewed the ergonomics process at a large automotive manufacturing company. Since program inception in 1989, the Company and the UAW have been industry leaders in developing a participatory ergonomics program at the plant level. Every large US facility has a locally controlled and operated cross-functional ergonomics team. In the years following implementation (1997-2001), extensive program development and team training have been well established. During program maturation, the organization as a whole has seen significant reductions in lost time case rate for cases of ergonomic interest (14.6%/year) and has had a strong decreasing trend for severity rate for cases of ergonomic interest (39.5 days/year). The local level teams are evaluated on their adherence to the ergonomic program with the use of process metrics including internal audits, OSHA compliance, and intervention activity level. The jointly designed process was developed with the intent of reducing injury rates (outcome metrics). This paper will evaluate the correlation between the ergonomics program outcome metrics and the process metrics.
    Railroad Yard Safety: Perspectives from Labor and Management BIBAFull-Text 1201-1204
      Stephen J. Reinach; Judith B. Gertler
    Safety in the U.S. railroad industry has improved markedly over the last two decades. Train accident and employee injury rates have both declined sharply. While current railroad accident and injury rates are low in comparison to other modes of transportation, these rates in railroad yards far exceed the overall accident and injury rates across the entire railroad industry. To assist the U.S. railroad industry in its efforts to improve safety, the Federal Railroad Administration initiated research to examine worker safety issues in yards. Part of this research effort involved conducting structured interviews with railroad management and focus groups with railroad labor. A number of safety-related topics were addressed, such as overall safety climate, safety incentive programs, and training. Methods of data collection are described, results of the structured interviews and focus groups are presented, and opportunities for improving safety in the railroad industry are identified.
    Ergonomic Improvements at an Electric Appliance Company in Korea BIBAFull-Text 1205-1209
      Kwan S. Lee; Dong K. Lee; Jae H. Kim; Mun J. Jung
    The objective of this paper is to present ergonomic improvements made at the electric appliance company in Korea. The Ergonomics Society of Korea has been sponsoring the Ergonomic Design award for workplace design. For this award, an ergonomic study was conducted to improve workplaces to reduce musculoskeletal problems for six months. All processes were first evaluated by workers and processes which were identified as problematic were analyzed by the company-wide committee to set the priority of improvement. Then an ergonomic improvement team consisted of a safety and health personnel, process engineers, and a management innovation personnel worked on the processes using a low cost approach. It was found that applying ergonomics at a low cost (1.25 million) could improve technically advanced workplaces and resulted in increasing productivity (10-30%) and cost saving (approximately 17.01 million) and improved the safety level.
    A New Model of How People Investigate Incidents BIBAFull-Text 1210-1214
      C. G. Drury; K. Woodcock; I. Richards; A. Sarac; K. Shyhalla
    We used a simulation methodology to provide a direct measurement of how incidents and accidents are investigated. Thirty-seven aviation maintenance personnel with incident investigation experience investigated are six incident scenarios that we developed from actual maintenance incidents. Using a methodology developed by Woodcock and Smiley (1999), participants were given a brief incident description and had to question the experimenter to determine how the incident happened. We counted the number and types of information requests, and recorded their sequence. Based on the sequence data we propose a five-stage model of incident investigation. An initial trigger initiates an interactive data collection/data analysis period, starting by determining spatial and temporal boundaries then investigating in a somewhat sequential manner. A stopping rule is used to determine when to stop investigating and begin the final reporting stage. The number of facts considered grows during the investigation stage, but then decreases at the reporting stage. Thus, basing recommendations on the reports of incidents may not consider all causal factors.

    INDUSTRIAL ERGONOMICS: Industrial Ergonomics Posters

    Effects of Level of Automation on Errors and Consistency in Two- and Three-Dimensional Anthropometry BIBAFull-Text 1215-1219
      David Feathers; Victor Paquet; Colin Drury
    This study investigated some potential sources of error, and their consequences, across different types of anthropometric measurement methods. The measurement methods included use of traditional anthropometric instruments, as well as two versions of an electromechanical approach that recorded three-dimensional locations of body parts. Several errors were hypothesized to be from aspects related to human information processing and their interaction with differing methods. Measurements obtained with the traditional approach and two versions of the electromechanical approach were then compared for two experienced anthropometrists who each took 72 measurements on a cadaveric forearm while it was clothed and unclothed. ANOVA demonstrated that there were differences in measurement consistency between individuals, measurement methods and clothing conditions. This study was an initial attempt to investigate the potential sources of error within anthropometric measurements via focusing on the information presented to the measurer and the application of this information to the consistency of measurement. The findings provide information about the causes of error and the saviors of consistency.
    Prelimenary Evaluation of Visibility in Hazardous Materials Level a Suit BIBAFull-Text 1220-1223
      John P. Holmquist; Par Ostberg; Par Axelsson; Nino Gallini; Mike Landsberger
    This paper evaluated the problem of visibility of a hazardous materials (hazmat) responder while wearing a level A hazmat suit. An experiment was performed to judge the amount of time a level A hazmat suit can be worn in normal working conditions without fogging and reducing visibility. After an initial evaluation, hypothesis and alternatives to prevent the fogging of the suit were formed. An experiment was performed testing the alternatives of antifogging agents to physical moisture barriers. From the experiment, a short-term solution, the use of anti-fog spray, and a long-term solution, the use of a cone shaped moisture barrier, were formed to correct the visibility problem facing the users of this suit.
    The Effect of the Postures of the Middle Finger and the Wrist upon the Movement of the Index Finger: Preliminary Studies BIBAFull-Text 1224-1226
      John P. Holmquist
    This paper created a preliminary index of the range of motion of the index finger with the effect of the middle digit suspended at minimum and maximum flexion. A follow-up study was performed creating a preliminary index of the range of motion of the fingers on each hand and the effect of the wrist joint suspended at minimum and maximum flexion. The resulting indexes can be used by professionals to study the average limitations, by designers to build better tools, and by researchers to further the fields of anthropometries, biomechanics, and the arts.
    An Ergonomic Evaluation and Redesign of Office Workstations to Decrease Reported Musculoskeletal Discomfort Using an Internet-Based Office Erogonomics Program BIBAFull-Text 1227-1231
      J. D. McGlothlin; R. C. Lee
    An ergonomic evaluation of 100 office spaces at a Midwest chemical manufacturing plant in the United States was conducted from May through October 2001. An internetbased office ergonomics program was used to find discrepancies between the recommended and actual measurements taken of employee workstations at the time of the assessments; to make appropriate adjustments; to purchase ergonomic equipment and furniture (when simple adjustments could not be made); and to administer musculoskeletal discomfort surveys. Thirty-three employees were selected for follow-up assessments at least one week after all adjustments were made, using the same procedure as the first assessments. These workers were chosen based on severity of reported discomfort ratings, greatest need for workstation changes (i.e., actual versus recommended workstation measurements), and amount of new furniture received or equipment installed. Of these 33 participants 28 were able to complete the post assessment. A comparison of the two assessments showed that more than 54% of the employees reported reduced musculoskeletal discomfort after adjustments were made and ergonomic furniture was added to their workstation.
    An Ergonomic Analysis of Scale-Pits BIBAFull-Text 1232-1236
      Cleve Mortimer; Pamela McCauley-Bell
    Much of the scale industry involves weighing large amounts of a product. The main method is the truck or railroad scale. These require pits to hold the lever systems necessary to weigh the truck or railroad car. However, these pits are designed with no thought for the safety of the technicians who maintain the scales. In this paper, four problems with current pit design were examined using data on the physical dimensions and the types of injuries possible. Three experiments were conducted to examine the risks of falling due to loss of balance, problems caused by moving around in the pit, and the effect of poor lighting. Using this data, suggestions are made to improve the safety of the scale pits for the technicians who work in them.
    Effects of Balance Training on Postural Stability BIBAFull-Text 1237-1240
      Jennifer M. Schmit; Deanna I. Rejacques; Michael A. Riley
    The present study is designed to address the relationship between postural sway and balance training. We compared postural sway in a group of trained dancers to a group of physically fit, untrained participants (control group) in order to assess enhanced postural control with balance training, particularly under challenging balance conditions. We varied the difficulty of postural control by using two surface conditions (rigid surface, foam surface) and two visual conditions (eyes open, eyes closed), factorially combined. The data were evaluated using 1-between (group) x 2-within (vision and surface) analyses of variance (ANOVA). The three dependent variables were the standard deviation of the COP time series in the anterior-posterior (AP) and medial-lateral (ML) axes, and the COP path length. Significant main effects were found for surface and vision and the surface*vision interaction in all conditions. Significant group differences were found in the AP and ML axes. The results of this study indicate that balance training enhances the control of posture. Thus, it may be useful to provide balance training to workers who must operate under conditions that threaten balance.

    INTERNET: Usability Methods, Design, and User Perceptions [Lecture]

    Conditional Branching in Computerized Self-Administered Questionnaires on the World Wide Web BIBAFull-Text 1241-1245
      Kent L. Norman; Timothy Pleskac
    Conditional branching is used to direct respondents to skip inappropriate questions or to answer follow-up questions. When surveys are implemented on the World Wide Web, branching can be automated in different ways. Three implementations of conditional branching in Web-based surveys were compared: (a) a manual form which replicated the paper-and-pencil version in a scrollable window, (b) a semi-automatic form which also showed the whole survey but auto-scrolled to the next question, and (c) an automatic form that displayed only one item per screen and implemented all branching. The surveys used involved one, two, or three follow-up questions. The automatic item-by-item implementation proved significantly faster than either the manual or the auto-scrolling versions. Respondents found the auto-scrolling to be disorienting. These results suggest that automatic branching should be used but with graceful jumps that guide the respondents' focus of attention without loosing it.
    The Online Experience and Consumers' Perceptions of e-Commerce Security BIBAFull-Text 1246-1250
      Carl W. Turner
    An experiment was conducted to determine the effects of users' interactions with e-commerce web sites on their perception of the security of the sites. Thirty-four participants performed a few typical tasks on three unfamiliar web sites, then rated the sites for visual presentation and ease of navigation, rated the credibility of 3rd party endorsers and technical security information, noted references to secure processes, then provided a judgment of the sites' security. Multiple regression analyses revealed that visual presentation predicted users' perception of security on all three sites. Additionally, navigation and number of references to security contributed to a security model for individual sites. The willingness to purchase from a site was highly correlated (.88) with the perception of site security. The article presents a model of security perception and provides empirical evidence for claims that security and trust are determined by visual presentation rather than technical security knowledge.
    Using Impenetrable Borders in a Graphical Web Browser: Are All Angles Equal BIBAFull-Text 1251-1255
      J. Shawn Farris; Keith S. Jones; Brent A. Anders
    Impenetrable borders can be created by placing graphical user interface targets (e.g., buttons, scroll bars, etc.) on the edge of a computer display. Research demonstrated that targets with impenetrable borders (edge targets) are selected faster than targets of the same size that are not against the edge of the screen (non-edge targets). This paper discusses the reasons why edge targets are selected faster than non-edge target and points out a critical weakness in past research on impenetrable borders. Specifically, researchers have always placed targets at a 90° angle from the cursor's origin, thus forgoing any ecological validity. Accordingly, an experiment is reported that tests the effectiveness of impenetrable borders when approach angle varies on a graphical web browser interface. Results indicate that impenetrable borders are effective across all of the approach angles used. These results support the recommendation to place commonly used targets at the edge of the screen whenever possible.
    Which is a Better Method of Web Evaluation A Comparison of User Testing and Heuristic Evaluation BIBAFull-Text 1256-1260
      Tan Wei-Siong; R. R. Bishu
    Besides recognizing the importance of incorporating usability evaluation techniques in the design and development phase of any user interface (UI), it is also very important that designers recognize the benefits and limitations of the different usability inspection methods. This is because the quality of the usability evaluation is dependent on the method used. Two of the more popular usability evaluation techniques are user testing and heuristic analysis. The main objective of this study was to compare the efficiency and effectiveness between user testing and heuristic analysis in evaluating four different commercial websites. Comparing the proportion of usability problems and the type of problems addressed by these two methods both in the early and later stage of the design process does this. The results showed that both user testing and heuristic analysis addressed very different usability problems and with the exception compatibility and security and privacy problems, where heuristic analysis outperforms user testing, both methods are equally efficient and effective in addressing different categories of usability problems.
    The Consumer Decision-Making Process in Two Different Web Stores BIBAFull-Text 1261-1265
      Sri Hartati Kurniawan; Yim Lee Au; Jing Zeng; Richard H. Y. So; Mitchell M. Tseng
    This paper reports on Consumer Decision-Making Process (CDMP) strategies in Web-based shopping in two different Web stores, one selling gifts and other selling mobile phones. Results indicate that the occurrence of a 'non-compensatory' (i.e., eliminating product alternatives by their attributes) CDMP strategy when the participants were viewing a single Web page with more than four product alternatives was significantly higher than with three or less product alternatives. Indeed, when the number of products on a single page of the gift store reached 16 or more, the occurrence of the 'non-compensatory' CDMP strategy was 100%. The results also indicated that the higher the number of products on the screen, the lower the percentage of products considered. Problems associated with the use of the think-aloud technique to measure CDMPs associated with Web shopping are discussed.
    Internet Usability and Customer Experience BIBAFull-Text 1266-1270
      Marc L. Resnick; Julian Sanchez
    The boom and bust of the dotcom mania has provided some significant wisdom to the general business community. Many of the now defunct dotcom companies were focused solely on customer acquisition. The more people who visited the site ("eyeballs"), they reasoned, the better their business would fare. This was generally accomplished through sub-cost prices and marketing gimmicks. Unfortunately, this led to a price-sensitive customer for whom the competition was only "a click away." The failure of these companies, and of the business model they engendered, has led to an increased focus on customer loyalty. It turns out that developing a core of loyal, long term customers provides a much better return on investment and a sustainable business model. It is far cheaper to retain an existing customer than to acquire a new one and repeat customers spend over twice per year what new customers spend. Customer loyalty evolves as a company meets the short term and long term needs of its customers. Some of these needs may be the overt, explicitly stated needs such as buying a pair of shoes. Other needs may be more intrinsic and emotion-based, such as the need to feel part of a community or to feel safe and protected. Companies that satisfy both kinds of needs stimulate customer loyalty, while those that do not experience significant customer churn. The term that has evolved to denote the degree of satisfaction of these needs is customer experience.

    INTERNET: Search Performance and Usability Issues [Lecture]

    The Effects of Web Search Engine Query Ambiguity and Results Sorting Method on User Performance and Preference BIBAFull-Text 1271-1275
      David N. Aurelio; Ronald R. Mourant
    Users of Web search engines report two main problems: an insufficient number of relevant results and the mixing of relevant results with irrelevant results. Therefore, this research investigates the effects of query ambiguity and three forms of sorting search results on user performance and preference. Forty-eight Web search engine users evaluated three forms of sorting results. For each task, the query was a single term that had one, two, or three meanings. The results indicated that the preferred results sorting method was affected by the page number of the correct results. When the correct results were all located on the same page (i.e., the first page), the participants preferred the Ranking, Disambiguating, and Categories methods when the query term had one, two and three meanings, respectively. When the correct results were not on the first page, the test participants preferred the Categories sorting method for all number of query meanings.
    How Good is Search Engine Ranking A Validation Study with Human Judges BIBAFull-Text 1276-1280
      Behnak Yaltaghian; Mark Chignell
    A study is reported where the rankings assigned by a search engine (Google) to the top 100 hits for seven queries are compared with the ratings of human judges (six per query). As assessed by correlations, agreement between judges was relatively good across all the queries, with a mean (Pearson) correlation of .475. In contrast, the correlations between Google rankings and human judges in this study were significantly lower, with a mean of .153. This study suggests that a high priority should be placed on finding improved methods for ranking the initial set of search engine results, so that they are more in line with human judgments of relevance.
    The Grid Menu: Efficient and Robust Selection of Menu-Items BIBAFull-Text 1281-1285
      Hong-In Cheng; Patrick E. Patterson
    With the increasing use of e-business web sites, users are often asked to select a menu-item from a large numbers of options. In this research, the pull-down menu, fisheye menu and grid menu were tested to compare the performance time, error rate, user satisfaction, simplicity, user friendliness, usefulness, and overall user preference of each menu type. The grid menu was more efficient in selection speed than the pull-down and fisheye menus when the number of menu-items was 50 and 100. The time needed to choose a menu-item with a grid menu was less affected by the size of menu and the physical location of an item within a menu. The pull-down and the grid menus were considered to be more satisfactory, simple, user friendly, and useful than the fisheye menu. 42.3 percent of subjects indicated that the grid menu was their preferred selection tool among the menus. The grid menu is an efficient and robust alternative menu choice for small and middle size menu lists.
    Using the Locus of Control Personality Dimension as a Predictor of Online Behavior BIBAFull-Text 1286-1290
      Bonnie L. Lida; Barbara S. Chaparro
    Since the 16th century, the availability of communication technology has advanced the level and accessibility of commerce and personal freedoms. The advent of the computer as a personal communication tool has given individuals new power in their ability to communicate, gain information, and make decisions. A major paradigm shift has been in the control that the individual now has in a consumer role. The internet has provided consumers a vehicle by which they can actively participate in the decision-making process -- from need recognition to post-purchase evaluation. Little research has been done to explore the personality characteristics of internet users.
       This study examines one aspect of personality, locus of control, and internet behavior. Research findings reveal substantial differences in internet usage and attitudes between a consumer's internal or external locus of control orientation. Results and future research relative to this study are discussed.
    Understanding Query Formation in the Use of Internet Search Engines BIBAFull-Text 1291-1295
      Jennifer A. Bandos; Marc L. Resnick
    Internet search engine use is notoriously challenging and frustrating to typical users. Most users are inefficient at finding what they are looking for and often give up before achieving their goals. Most commercial search engines have advanced search interfaces that are designed to facilitate increased precision and recall, but users generally avoid these due to poor usability and high perceived difficulty of use. This paper outlines three studies that investigated the strategies and effectiveness of user-generated search queries. Scenarios were formulated to encourage users to construct the single best query for each task. In general, users were unable to construct accurate queries for tasks that required compound logic. Study 1 verified the reluctance of users to use advanced search features. Study 2 investigated the use of Boolean and proximity search commands and capitalization strategies. Participants generally did not use them properly. Study 3 compared the use of basic search with advanced search when users were forced to use each one. Performance was similar but preference measures showed a significant advantage for basic search while confidence was higher for advanced search.

    INTERNET: Internet Posters

    Paging vs. Scrolling: Examining Ways to Present Search Results BIBAFull-Text 1296-1299
      Michael Bernard; Ryan Baker; Barbara Chaparro; Marisa Fernandez
    This study examined the performance and preference of individuals searching for information presented within search results that were displayed in either mostly paging or mostly scrolling formats. The conditions were: ten links per page at ten pages, fifty links per page at two pages, and one hundred-links on one page. Overall, the fifty-link condition had the fastest search time and was the most preferred. Users perceived that the hundred-link condition was more difficult to find information, presented too many choices, and looked less professional than the ten-link condition. The results suggest that a moderate amount of paging and scrolling was optimal. However, when forced to choose between the two, users preferred paging, even though paging took more time to find information than did scrolling.
    Using Impenetrable Borders in a Graphical Web Browser: How Does Distance Influence Target Selection Speed BIBAFull-Text 1300-1304
      J. Shawn Farris; Keith S. Jones; Brent A. Anders
    Impenetrable borders are edges of graphical user interface targets (e.g., buttons, scroll bars) that the mouse cursor cannot cross. Research has shown that targets with impenetrable borders (edge targets) are selected faster than targets without impenetrable borders (non-edge targets). In addition, prior research determined that the effectiveness of impenetrable borders is maximal between .50 and 11.75 cm distance from the cursor's origin to the target. However, this is a broad range and a more specific estimate of distance would be useful for designers wishing to maximize the effectiveness of impenetrable borders. Accordingly, the reported experiment searched for the critical distance where impenetrable border effectiveness asymptotes using a graphical web browser interface. Results indicate that impenetrable border effectiveness asymptotes between .50 cm and 3.50 cm distances. These results support past research and make a more detailed design recommendation. An example of a redesigned interface incorporating impenetrable borders is given.
    Usability Issues in Advanced Distributed Learning Applications: What Are the Implications for Learning BIBAFull-Text 1305-1309
      David O. Holness; James A. Pharmer; Wendi L. Buff
    This paper describes the results of data collection that occurred during the alternative format session presented to the 45th annual meeting of HFES. During the session, six participants were briefed on fuzzy logic as an alternative to regression for analyzing policy-capturing data and on usability issues associated with Advanced Distance Learning (ADL) applications. Participants then rated the extent to which usability violations impacted learning in three different ADL environments. After the conference, the validity of the regression and fuzzy models were assessed across the three ADL applications. In addition, exploratory analyses were performed in order to gain insight into the relative impact of usability principles on learning in ADL applications. Results revealed no statistically significant differences between the predictive validities of either modeling technique across the ADL applications. In addition, judgements of which usability violations had a more negative impact on learning did depend on the type of ADL application.
    Examining Information Searching on the World Wide Web with a Screen-Reader: A Verbal Protocol Analysis BIBAFull-Text 1310-1314
      Keith S. Jones; J. Shawn Farris; Peter D. Elgin; Brent A. Anders; Brian R. Johnson
    Recently, assistive devices designed for computer systems have proliferated, including those designed to support users with visual impairments (i.e., screen-readers). However, research examining how individuals use screen-readers to access the Internet is virtually non-existent. Therefore, the purpose of the reported study was to examine the behavior of a user with visual impairment, via protocol analysis, while using the World Wide Web to find information. We classified her behavior into an HCI-relevant model, i.e., Norman's (1988) seven stages of action, in order to identify potential usability bottlenecks. The results indicated that executing actions and, more notably, interpreting the system state were the most frequent and time-consuming tasks. In addition, the results suggested that the user had difficulty determining the effects of her control inputs on system status, as well as determining whether or not goal-relevant information was present on the current page. For screen-reader design, this suggests that there are possible usability problems in interfacing the user with the screen-reading software and the way textual information is aurally displayed to the user.
    Do Common User Interface Design Patterns Improve Navigation BIBAFull-Text 1315-1319
      Carlos A. Maldonado; Marc L. Resnick
    The Internet has become a growing channel for consumer purchases. Half of all U.S. consumers made at least one purchase on-line in 2001. However, many consumers report frustration with the lack of support for navigation within many Internet retailers' web sites. Several design patterns have been suggested to overcome these limitations, such as expanded hierarchies and breadcrumbs. This study investigated the effects of these design patterns on users' quantitative performance and subjective preference for ecommerce web sites. Expanded hierarchies, a design pattern that is commonly used by many retail web sites, degraded all of the performance metrics assessed in the study. Users required more time, made more errors, used more clicks, and had lower satisfaction scores for sites designed with expanded hierarchies. The results for breadcrumbs suggest that they may improve performance. The inclusion of breadcrumbs reduced the number of clicks required by users to complete the tasks, but other performance metrics did not reach statistical significance. The results indicate that design patterns that are believed to improve performance a priori may not yield the results expected.
    International Interface Evaluation of a Corporate Web Site: Assessing the Effectiveness of Communicating with Culturally-Diverse Audiences BIBAFull-Text 1320-1324
      W. Todd Nelson; Anna L. Langhorne; David L. Mahaffey
    In order for international corporations to establish a successful global Web presence, their Web sites must be designed to effectively communicate with culturally-diverse users. Employing a methodology that assesses the extent to which the intended meaning of interface elements (e.g., navigation, graphical elements, and site functionality) are understood by culturally-diverse users, international usability testing of a translated US corporate Web site was conducted in Brazil, France, Spain, and Germany. Participants included professionals from telecommunications, marketing research, and financial services sectors. Results indicated that the site's interface was language- and context-dependent and that it varied across cultures. Primary navigation categories were generally well understood across all cultures; however, the effectiveness of secondary, tertiary, and image-based navigation varied across cultures. Basic search functionality was effective, but advanced search features were less meaningful and culturally-dependent. In addition to presenting research outcomes, the effectiveness of this methodology for international interface evaluations is discussed.

    MACROERGONOMICS: Macroergonomics [Lecture]

    Investigating Total Exposure to MSD Risks: The Roles of Occupational and Nonoccupational Factors. BIBAFull-Text 1325-1329
      Alan Hedge; Mary Rudakewych; Lisa Weitz
    The role of nonoccupational risk exposures on reports of musculoskeletal disorders (MSDs) among full-time computer workers was investigated for 403 State office employees. The non-occupational risk exposures involving repetitive hand motions that were assessed included home computer use, domestic activities (gardening, home maintenance), hobbies (e.g. knitting) and sports (e.g. volleyball). Reports of MSDs were significantly elevated by both occupational factors (duration of keyboard use without a rest break, typing speed, typing skill) and nonoccupational factors (home computer use, gardening, crocheting and needlepoint). Reports of MSDs were not significantly affected by other occupational factors (hours of keyboard and/or mouse use, wearing corrective lens, number of times getting out of the chair) or nonoccupational factors (knitting, golf, tennis, racquetball, volleyball). The results indicate that MSD symptom reports may be the result of total exposure to certain risk factors both in and outside of the workplace.
    Telecommuting: An Overview of Emerging Macroergonomics Issues BIBAFull-Text 1330-1334
      Michelle M. Robertson; Wayne S. Maynard; Yueng-hsiang E. Huang; Jamie R. McDevitt
    Advances in information technology are allowing selective employees to work "anywhere" and at "anytime." The work location for some employees is changing from the traditional corporate office to a virtual work location, such as the home, hotel, airport, shared and satellite office, client office and the car. This trend toward "alternative work styles" and the distributed workforce is likely to continue. As these work styles and virtual workplaces continue to emerge, understanding and designing effective work systems using a macroergonomics perspective is essential to achieve the benefits of distributed work and telecommuting. In this paper, we will provide an overview of the major macroergonomics issues associated with telecommuting. First, we present the literature databases used for this paper, a macroergonomics perspective and model. Next, examples of telecommuting programs, including the organizational structure, implementation process and evaluation strategy are given. A review of the existing empirical research concerning telecommuting and its implications are also discussed. Further, a macroergonomics process for managing the health and safety of telecommuters is described. In summary, a discussion of future telecommuting research and program development using a macroergonomics, work system design approach, is given.
    A Macroergonomic Approach to Distributed Team Performance BIBAFull-Text 1335-1339
      Haydee M. Cuevas; Stephen M. Fiore; Eduardo Salas; Clint A. Bowers
    With the structure of teams in organizations increasing in complexity to include both co-located and distributed team members, explicit linkages between theory and practice are critically needed to mitigate the negative effects that computer-mediated interaction may have on distributed team performance. Following a macroergonomic approach, this paper focuses on describing how theories from organizational psychology can address some of the challenges faced by this small, but growing, subset of teams. Specifically, theories in motivation, group dynamics, and decision making can be applied to offer practical guidelines to foster the development of positive team attitudes (e.g., cohesion, trust) and behaviors (e.g., goal-setting, self-regulation), and successful decision making performance in distributed teams.
    Team Implementation of New Technology BIBAFull-Text 1340-1344
      Dennis R. Jones; Michael J. Smith
    New technology is dramatically changing the workplace by allowing companies to increase efficiency, productivity, quality, safety, and overall profitability. An effective new technology implementation is required for companies to compete successfully in the global marketplace. Time and money wasted on unsuccessful and improper new technology implementation is counterproductive to the overall goal of improving the competitiveness and profitability of the company. Teams and teamwork have been recommended as a way to improve efficiency, productivity, quality, safety, profitability, and employee satisfaction. With the utilization of total quality management (TQM) and quality improvement (QI), each of which rely on teamwork, new technology implementations have been more successful. New technology challenges the current state of traditional implementation methods and techniques. To effectively utilize these new technologies it is best to consider all of the factors involved in the implementation process; most importantly the human elements involved. It is recommended to utilize a cooperative team oriented approach to new technology implementation, which relies heavily on soliciting employee input and participation throughout the entire process. By doing this; it is hoped that the new technology can be implemented in the most effective way possible. A case study is presented to illustrate this.
    Mission Control Knowledge Synchronization: Operations to Reference Performance Cycles BIBAFull-Text 1345-1349
      Sandra K. Garrett; Barrett S. Caldwell
    Capturing and utilizing previously generated knowledge is crucial to an organization's development and responsiveness in a dynamic environment. Even so, the creation of a reference source from operational knowledge is affected by situational contexts, events, and organizational constraints. The organizational operations to reference cycle within NASA's Mission Control Center can be examined by the approval process of Flight Rule Change Requests (FRCRs). The FRCR process is intended to document knowledge capture and synchronization tasks associated with space flight missions. External pacing exists due to the operational demands of the launch schedule; procedures are not written or modified without direct relation to operational experience or mission requirements. Preliminary analysis illustrates that, although the FRCR approval process has a cyclic nature with a natural frequency of about one month, launches act as critical forcing functions since procedural knowledge and controller expertise must be synchronized before each mission.
    Macroergonomics Methods: An Overview BIBAFull-Text 1350
      Hal W. Hendrick
    This symposium briefly overviews a number of the classical methods as they have been adapted for application to macroergonomics and a series of methods that have been developed specifically for macroergonomics research and application, based on sociotechnical systems theory and research.
    Participatory Ergonomics and Macroergonomic Organizational Questionnaire Surveys BIBAFull-Text 1351-1354
      Pascale Carayon; Peter Hoonakker; Maria C. Haims
    In this paper we describe a participatory ergonomics framework and we show how macroergonomic organizational questionnaire surveys can be used within this framework to support and sustain worker participation in the identification of ergonomic problems and solutions and the implementation of change. An example is presented of how the participatory ergonomics conceptual framework is implemented in a work organization intervention study.
    Macroergonomic Methods: Interviews and Focus Groups BIBAFull-Text 1355-1359
      Leah C. Newman
    Both the interviewing and focus group processes have been around and in use as tools for gathering information for decades. For someone who is interested in learning more about people and their experiences, what better way to accomplish this than by speaking directly with an individual or group of individuals? Individual as well as group interviews are windows to an understanding of the behaviors of those being interviewed. Focus groups, specifically, are viewed as a window into the human condition and human interaction. Although, the individual interview is one of the most widely used methods for collecting qualitative data, focus groups have recently gained more popularity among qualitative researchers as a method of choice.
    Field Study, Field Experiment, and Macroergonomic Analysis of Structure (MAS) Methods BIBAFull-Text 1360-1364
      Hal W. Hendrick
    The field study and field experiment methods, as adopted for macroergonomics applications, and the macroergonomic analysis of structure (MAS) method are described.
    Macroergonomic Analysis and Design (MEAD) of Work System Processes BIBAFull-Text 1365-1369
      Brian M. Kleiner
    The MacroErgonomic Analysis and Design (MEAD) methodology can guide institutional data collection and analysis to determine the risks and causal factors leading to experiments that will help with new design and intervention strategies. To illustrate, the example of reducing slips and falls in health care facilities will be applied. This is an area of collaboration currently between the Macroergonomics Laboratory and the Locomotion Research Laboratory.
    A Macroergonomics Tool for Assessing Work System Processes: Systems Analysis Tool (SAT) BIBAFull-Text 1370-1373
      Michelle M. Robertson
    A macroergonomics tool for assessing work system processes, the Systems Analysis Tool (SAT) is described. The seven-step methodology is discussed involving defining the problem and, developing and evaluating strategic systematic solutions. An evaluation scorecard which includes an Economic Advantage analysis is used to determine the cost/benefits of each proposed alternative or program solution based on direct and indirect costs and compensation. A decision criteria table is constructed providing a basis for a trade-off comparison of micro-ergonomic and macroergonomic alternative solutions. The benefit of the SAT is the integration of micro- and macroergonomic approaches for solving organizational problems. Work system changes implemented by companies that incorporate a macroergonomic, systems approach demonstrate positive results in minimizing negative health effects based on financial and indirect costs and improved employee and business unit effectiveness.
    Macroergonomics and Diversity: Education, Healthcare and the Workforce BIBAFull-Text 1374
      Leah C. Newman
    In the 21st century, we find societies and communities still plagued by poor education, inadequate healthcare, as well as a lack of job opportunities. Macroergonomics provides a systems approach to solving complex problems. Furthermore, macroergonomics methods can be used to apply interventions to education, healthcare and workforce systems problems in an effort to increase the effectiveness of societal activities, improve the quality of life, enhance human dignity and develop human capabilities.
    Women of color and the selection of IT academic programs BIBAFull-Text 1375-1378
      C. A. Brooks
    Reasons for the selection of IT fields by women of color were investigated. The factors of interest were high school & college IT courses (defined as math, sciences and computer sciences), GPAs and perceived student-teacher access. The lack of IT field selection was significantly driven by the intensity of math & science requirements. Some of the recommendations to encourage girls' and women's interests in IT fields are mentioned.
    Quality of Working Life among Women and Minorities in the Information Technology Workforce: A Pilot Study BIBAFull-Text 1379-1383
      Pascale Carayon; Maria C. Haims; Maria J. Brunette; Peter Hoonakker
    In this paper we present preliminary results of a pilot study aimed at assessing a questionnaire survey on quality of working life and diversity in the Information Technology Workforce.
    Enhancing Patient Safety and Quality of Care Using a Macroergonomics Systems Approach BIBAFull-Text 1384
      Maria C. Haims
    There is a clear recognition that human factors and systems approaches to patient safety, quality of care and medical error analysis research are needed (e.g., Leape 1997). Most human factors research on patient safety has focused on studying and explaining the complexities of human error and how to reduce its occurrences or consequences (e.g., Reason, 1990; Cook and Woods, 1994). Researchers have concluded that systems factors (also termed latent factors) are the primary causes of errors, and that they must be addressed in order to reduce errors and improve quality of care (e.g., Leape et al., 1995). Noticeably missing from the patient safety literature, however, are studies that empirically examine systems design, quality management, and organization and job design in relation to patient safety, medical error reduction and quality of care. These issues, which are essential elements of the health care system, can collectively be described as macroergonomics.
    A Macroergonomic Case Study Assessing Electronic Medical Record Implementation in a Small Clinic BIBAFull-Text 1385-1388
      Ann Schoofs Hundt; Pascale Carayon; Paul D. Smith; Vipat Kuruchittham
    In this paper we describe preliminary results of a case study assessing macroergonomic aspects of the implementation of an electronic medical record (EMR) in a small family practice clinic.
    Infection Control/Health Care Epidemiology and Human Factors Engineering A New Pairing for Patient Safety BIBAFull-Text 1389-1393
      Carla J. Alvarado
    This paper covers the history of infection control and the role human factors engineering, and macroergonomics in particular, has played and will continue to play in the reduction of hospital-acquired or nosocomial infections -- a key aspect for enhancing patient safety and quality of care. Semmelweis is considered the father of modern hospital infection control and epidemiology programs; and he used human factors engineering and a systems approach to solve infection control problems by considering societal, organizational, environmental, task, tools and person factors in his investigations. Today, the IOM stresses the importance of organizational and process designs and a "culture of safety" for the reduction of medical errors. Examples of current problems and areas for future infection control and human factors research are presented, including design issues, change management and safety culture. All levels of the work system -- from the microenvironment level issues such as noise and light to the macro environment level issues such as organizational culture and societal factors -- must be taken into account for controlling nosocomial infections and enhancing patient safety.
    A Framework and Methodology for Achieving Region-Wide Patient Safety Improvements BIBAFull-Text 1394-1398
      Marla Haims; Denise Rousseau; Donna Keyser; Ed Harrison; Carl Sirio
    Adverse patient events, including nosocomial (hospital-acquired) infection rates and medication errors, are among the nation's most pervasive patient safety problems. The Pittsburgh Regional Healthcare Initiative (PRHI), a regional coalition for healthcare quality improvement, has identified the elimination of medication errors and nosocomial infections as a primary goal. PRHI has facilitated the implementation and use of two different reporting systems in all 30 of its member hospitals designed to facilitate work toward this goal: 1) the Centers for Disease Control (CDC) National Nosocomial Infection Surveillance System (NNIS); and 2) the US Pharmacopeia (USP) MedMARx, a medication error reporting system. The aims of this study are to understand 1) how well the reporting systems and their standards of use succeed in generating usable information; 2) how well feedback review systems, related to the reporting, function; and 3) the problem-solving systems through which knowledge is translated into organizational and inter-organizational learning. The methodological approach reflects a systems view, includes several levels of analysis, and utilizes triangulation of both qualitative and quantitative data. Data collection components include hospital profiles, site visit interviews, structured diaries, surveys, intervention case studies and report design feedback forms, along with data collected from the reporting systems themselves.
    Job and Work Environment Predictors of Turnover Intention in Long-Term Care Facilities BIBAFull-Text 1399-1403
      Ben-Tzion Karsh; Bridget Booske; Francois Sainfort
    The purpose of this study was to examine whether job characteristics, the work environment, participation in quality improvement (QI) activities, and facility quality improvement environment predicted turnover intention in nursing homes. 6584 nursing home employees from seventy-six nursing homes in a midwestern state participated. A self-administered survey was used to collect the data. The results suggest that specific work organization factors, such as workload and work scheduling, can be manipulated to affect turnover intentions. The implications for retaining nursing home employees are discussed.

    MACROERGONOMICS: Macroergonomics Poster

    Safety Culture: A Concept in Chaos BIBAFull-Text 1404-1408
      Hui Zhang; Douglas A. Wiegmann; Terry L. von Thaden
    A growing number of studies have been conducted to define and assess safety culture in a variety of complex, high-risk, industries. The purpose of the present study was to review these efforts in order to gain a better understanding of the "safety culture" concept, along with the highly related concept of "safety climate." Results suggest that there exists considerable disagreement among researchers as to how safety culture should be defined and whether or not safety culture is inherently different from the concept of safety climate. These differences, however, are not generally due to the uniqueness of the industry or work domain being studied, since many researchers have focused on common domains (e.g., nuclear power). A synthesis of these various perspectives was conducted and hybrid definitions of both safety culture and climate are provided. Perhaps a common nomenclature and set of definitions will enable researchers to better share information and strategies for improving safety culture.

    MEDICAL SYSTEMS AND REHABILITATION: Medical Systems/Cognitive Engineering and Decision Making Joint Lecture Session [Lecture]

    Clinical Evidence at the Point of Care in Acute Medicine: A Handheld Usability Case Study BIBAFull-Text 1409-1413
      Harumi Takeshita; Dianne Davis; Sharon E. Straus
    The need to design medical information device interfaces for clinical use has been well documented in medical journals. In this study we apply well known usability techniques such as user requirement elicitation and prototype design and evaluation to design an evidence-based medical information retrieval system intended for a wireless environment. Our immediate goal is to make the daily practice of evidence-based medicine (EBM) for frontline clinicians easier by providing relevant, timely information at the point of care (using a wireless PDA device), delivered in a format that is usable and liked by the target group. Our objective is to use this evidence-based information delivery tool as an educational device and to encourage clinicians to consult, as appropriate, the latest best evidence available to support their clinical decision in hopes of improving clinical outcomes. The development of a handheld user interface for clinicians is described, along with results obtained from usability testing with a sample set of scenarios.
    Video Clips as a Data Source for Safety Performance BIBAFull-Text 1414-1417
      Colin Mackenzie; Yan Xiao; Peter Hu; F. Jacob Seagull; Camille Hammond; Grant Bochicchio; William Chiu; James O'Connor; Lynn Gerber-Smith; Richard Dutton
    Improved safety is an important goal, but there is difficulty in gathering data and identifying practices that lessen the margin of patient safety in real dynamic complex medical workplaces. Video clips as data are a rich source to examine safety performance. Video clips have utility for participants to review their activities and for analysts to extract quantitative data. Focusing video data collection around brief, risky but beneficial tasks, to illustrate patterns of use that occur in Trauma Centers during patients' resuscitation, can simplify participation consent, confidentiality and data analysis problems. However such video clip acquisition (5-15 minute duration) does not appear to compromise the quality of the content, that can facilitate identification of team performance, communication, ergonomic, and systems factors affecting patient safety. Comparisons of task performance under two levels of task urgency was particularly revealing of areas where patient safety performance can be improved and allowed identification of preventive strategies to minimize the effects of safety infractions.
    Repeating Human Performance Themes in Five Health Care Adverse Events BIBAFull-Text 1418-1422
      Emily S. Patterson; Marta L. Render; Patricia R. Ebright
    Public dread following well-publicized accidents energized the desire to learn from adverse events in health care. This paper summarizes an attempt to partner medical and human factors expertise to identify repeating human performance themes across adverse events. An interdisciplinary team interviewed 30 health care personnel from multiple facilities about five complex medical incidents. Ninety human performance themes were examined for each incident. Of these, ten human performance themes were identified to be salient in at least three of the incidents. Although none of these themes directly point to solutions, they increase our understanding of recurring themes across medical cases and can point to similar themes, and how they have been addressed, in other high-consequence, complex, socio-technical domains, such as aviation.
    Parallel User Interface Design of a Clinical Decision-Support Application for Desktop and Pocket PC Platforms BIBAFull-Text 1423-1427
      Robert Tannen
    In order to increase physician acceptance and use, it is necessary for clinical information systems to better support workflow and connectivity. Towards that end, it is advantageous to develop clinical applications that support a range of platforms and mobile devices. However, differences in design/development approaches, technical limitations, and user interactivity across devices result in inconsistent features and user experiences, limiting functionality, usability, and transfer of training. In the current project, a browser-based physician decision-support and order entry prototype was developed for the Windows desktop and Pocket PC in parallel. Corresponding functionality was implemented on both platforms via an iterative, user-centered design approach that utilized components of the desktop version to create the PocketPC screens. Subsequent physician feedback demonstrated high transfer of training from the desktop version to the PocketPC. The findings from this work can be applied to other multi-platform user interface projects.
    Transactive Responsibility Systems and High Reliability Teams: A Tentative Formulation BIBAFull-Text 1428-1432
      Yan Xiao; Jacqueline Moss; Colin F. Mackenzie; F. Jacob Seagull; Samer Faraj
    Understanding how teams perform successfully in high-risk settings can provide us with insights into the processes by which safety is created. Building upon previous field and laboratory studies, we propose a tentative formulation of a concept, transactive responsibility system, to account for the intricate, complex responsibility system emerged in team interaction. With a transactive responsibility system, a team can deal with the challenges of conflicting goals of training and performing and rapidly changing work environments found in many settings. A set of measurement proposals is made to illustrate the potential practical use of the concept. Potential impact on training is speculated.
    Seizing the Moment: Translating Human Factors Research into Patient Safety Interventions Panel BIBAFull-Text 1433-1437
      Thomas Sheridan; Emilie Roth; James Battles; Meghan Dierks; John Gosbee; Marta Render; Luke Sato
    The word is out. Doctors, nurses, and health care administrators have heard of human factors. They don't quite understand it, but they are willing to listen if they can see convincing evidence that it can help. To be effective instruments of change the human factors community needs to understand better what motivates physicians and nurses and hospitals to change, and how the health care system works. They need to get closer to the market, learn how to communicate with hospitals and medical practitioners, discover the opportunities for human factors services, and learn how to deal with the health care community to change the culture of blame to one of systems understanding and improvement. It is to that end that this panel was organized. The panel brought together managers, research funders, policy makers and medical educators who are actively engaged in trying to improve patient safety in hospitals to discuss needs, opportunities, and challenges to performing human factors research addressing health care concerns and translating the results of the research into practical interventions.

    MEDICAL SYSTEMS AND REHABILITATION: Human Factors Issues at the Point of Care

    Creating Patient Safety with Organizational Learning: A Case-Based Learning Intervention at a Public and Private Hospital BIBAFull-Text 1438-1442
      Amanda Eisenlohr; Marta L. Render; Emily S. Patterson
    A critical component of a high reliability organization (HRO) is believed to be a safety culture. Historically, healthcare placed the onus on individuals for perfection in performance of complex work. A six-month, case-based learning intervention at a public and private hospital, SafetyMinutes, attempted to shift the focus from the individual to systems. The intervention is organized in rotating modules of a medical and non-medical incident that exemplify a safety concept, displayed via posters in a staff meeting space, followed by a moderated discussion. Moderators asked how the stories resembled or differed from the nurses' experiences and guided participants away from ingrained "blame" responses in order to look more deeply at systemic and organizational factors. We assessed program effectiveness by ethnographic analysis of written transcripts of the moderated sessions and discuss lessons learned.
    A Team Performance Data Collection and Analysis System BIBAFull-Text 1443-1447
      Stephanie Guerlain; Thomas Shin; Hui Guo; Reid Adams; J. Forrest Calland
    At present there exists no commercially available product capable of capturing and broadcasting multimedia audiovisual data from teams performing high-risk work. We have developed such a recording and analysis system for the purpose of studying team behavior, which we currently use to observe and record up to 8 people working as a colocated team in a hospital operating room. The system has four data collection computers, each recording one video stream and up to 2 audio feeds. A separate software package is used to synchronize and view the audio/video streams together on a fifth computer. This software has several annotation and scoring features which can be used either for data analysis or for team debriefing purposes. Although currently being used for patient safety research in the operating room, this system could also be adapted to collect and analyze team behavior in other domains, even for participants who are distributed.
    Medication Dispensing Errors in Community Pharmacies: A Nationwide Study BIBAFull-Text 1448-1451
      Elizabeth A. Flynn; Nathan T. Dorris; Grady T. Holman; Brian J. Carnahan; Kenneth N. Barker
    The available literature concerning medication dispensing errors provides relatively few studies that focus on community-based pharmacies. This paper presents the results of a nationwide, observation-based study of dispensing errors. Although community-based pharmacies were the primary focus, a small number of health-system pharmacies were also included. Investigators collected information concerning the frequency and type of errors and near errors as well as data regarding a number of task and environmental factors previously correlated with dispensing errors. A total of 5,784 prescriptions were inspected, revealing 91 errors (1.57%) and 74 near errors (1.28%). Errors were categorized as either content (41.76%) or labeling (58.24%) errors. Results are consistent with findings in the available literature. In particular, lighting levels, type of inspection system used (e.g., bar code product verification), number of available employees, and the arrangement of drug stock were significantly associated with both types of errors.
    Reported Likelihood of Reading Over-the-Counter (OTC) Medication Labeling and Contacting a Physician BIBAFull-Text 1452-1456
      Deane B. Cheatham; Michael S. Wogalter
    The present research examined the extent to which consumers reported reading information on over-the-counter (OTC) packaging and labels. Two studies consisting of a total of 652 participants were conducted. Study 1 participants completed a survey in which they reported their OTC medication behaviors in terms of saving the packaging from the medication and the likelihood that they would contact a physician with OTC medication questions. In Study 2, participants completed a survey in which they reported the likelihood of reading information on the medication packaging and label both before and after using the product the first time. Results indicated that participants frequently discard the box after using medication and rarely call a physician with questions regarding OTC medications. Findings also indicated that information is more likely to be read prior to using medication than afterwards. Age, sex, and student status differences in reading behaviors were also found. Implications for the delivery of OTC medication information are discussed.
    An analysis of work activity in the operating room: Applying psychological theory to lower the likelihood of human error BIBAFull-Text 1457-1461
      Jonathan Levy; Daniel Gopher; Yoel Donchin
    We report on our observations in the operating room, where we examined the work activity in hopes of understanding why human errors can occur even with simple tasks (e.g., loading a syringe with the wrong solution). We employed a human factors analysis guided by our understanding of human cognition (memory, attention, action planning, etc.) with the goal of improving safety. By applying psychological theory (human cognition) to this real-world environment, we suggest where human error is prone to occur due to factors such as non-optimal procedures and design layout. We speculate that such weaknesses can contribute to adverse events and offer low-cost solutions aimed at minimizing the likelihood of such errors occurring.
    Human Factors Research in Patient Safety: A Candid Assessment Panel BIBAFull-Text 1462-1466
      Kerm Henriksen; Marilyn Sue Bogner; Pascale Carayon; Richard I. Cook; Matthew B. Weinger; Yan Xiao
    Five panelists, playing active research roles in the Agency for Healthcare Research and Quality's patient safety research initiative, present their views on challenges to human factors research for enhancing patient safety. Bogner advocates a systems structure for linking the findings of various research projects so that the missing pieces of the patient safety puzzle can serve as fruitful targets for subsequent research. Carayon adopts a macroergonomic framework for designing interventions to clinical work systems while Cook focuses on the complexity that underlies configurable clinical devices. With respect to anesthesia and critical care, Weinger cites the successful use of task analysis, workload assessment, and video analysis, yet notes challenges regarding concerns about patient privacy, disruption of patient care, and cultural barriers. Xiao cites impressive HF/E work on team coordination and performance shaping factors and sees the need for greater use of video and information technology to improve institutional learning and coordination of patient care.

    MEDICAL SYSTEMS AND REHABILITATION: Ergonomic and Training Issues in Medical Systems Development [Lecture]

    Investigation of the Relationship Between Workers' Perceptions and Compliance with Standard Safety Precautions in a Rural Hospital BIBAFull-Text 1467-1471
      Paul Hable; Alvaro D. Taveira; Ben-Tzion Karsh
    The practice of standard safety precautions in health care facilities is essential for the protection of health care workers from exposure to blood borne pathogens. Understanding the relationships between worker perceptions and behaviors can be central to the success of safety programs in health care facilities. A survey questionnaire was distributed to 174 health care workers who perform injections, venous access or arterial access procedures in a 110-bed facility located in a rural Midwest community. One hundred thirty-one were returned (response rate 75%). A stepwise logistic regression procedure was conducted having job category, gender, job tenure, and previous experience in a metropolitan location as covariates. Findings indicated that three of 15 examined risk factors predicted less than perfect compliance with standard safety precautions. Individuals reporting that they tear off glove fingers, that compliance is difficult, and stating that gloves make finding veins difficult all had significant odds of imperfect compliance.
    Dynamic Simulator for Training Clinical Breast Examination BIBAFull-Text 1472-1476
      Gregory J. Gerling; Geb W. Thomas; Alicia M. Weissman; Edwin L. Dove
    Clinical breast examinations (CBE) play a role in the detection of breast cancers. However, most physicians receive inadequate training in tactile search of breast tissue to detect small (< 2 cm), hard tumors. The dynamic, variable-lump, silicone breast simulator was designed to improve physicians' CBE performance and increase tumor detection. Water inflates balloons embedded in formed silicone to simulate the presence of tumors and allow independent adjustment of tumor hardness. The advantage, compared to static models with five, non-movable tumors, is that training scenarios can be reconfigured and repeated until each trainee learns the subtle tactile cues associated with tumors. In a study of 48 medical students, training with the dynamic simulator increased the number of tumors found (F(42)=7.85, p=0.0077), reduced the number of false positives (F(42)=5.20, p=0.0277), and improved transfer of training. This advancement can allow CBE to become more reliable, consistent, and effective.
    A Comparison of the Opinions of Nurses and Emergency Medical Workers Regarding Medical Device Usability BIBAFull-Text 1477-1481
      Laurie Reed; Jennifer Fisher
    In this study critical care nurses and emergency medical workers (including firefighters, emergency medical technicians (EMTs), and paramedics) were surveyed regarding their opinions of medical device usability. The goal of the study was to determine how the two populations fared in terms of general product understanding, proficiency, usability, and functionality. Furthermore, the study identified similarities and differences between the two populations, and explored areas of medical technology design upon which manufacturers can improve. Results showed that a major concern of both populations was training; nurses and emergency medical workers felt that workloads do not allow time for sufficient mastery of the devices. The respondents also felt that medical devices could be more consistent and less complex. Both groups indicated that it is most important to design products that are easy to learn, easy to use upon first use, and efficient to use longterm.
    Improving Assistive Technologies for the Visually Impaired: Minimizing the Side Effects of Magnification Products BIBAFull-Text 1482-1485
      Raegan M. Hoeft; Wendi L. Buff; Elizabeth Cook; Kay M. Stanney; Stacy Wilson
    This study focused on determining and minimizing the effects of motion sickness caused by feelings of vection during the use of magnification assistive technology (AT) products by the visually impaired. A prototype was developed that minimized hypothesized causes of vection in current magnification products. Data were collected from respondents to determine their current use, satisfaction and sickness levels when using magnification AT products. Participants then interacted with the prototype and similar data were collected. Results indicated that the prototype significantly reduced feelings of sickness and vection as compared to conventional AT magnification devices. Further research is warranted on other aspects of such devices that may contribute to adverse side effects.
    Dose-Response Relationship between Reach Repetition and Indicators of Inflammation and Movement Dysfunction in a Rat Model of Work-Related Musculoskeletal Disorder BIBAFull-Text 1486-1490
      Ann E. Barr; Mamta Amin; Mary F. Barbe
    The purpose of this study was to compare the effects of a high or low repetition reaching and grasping task on serum levels of interleukin-1α (IL-1α) and IL-1β and on reach performance in a rat model of work-related musculoskeletal disorder (MSD). Forty-seven rats reached repetitively for 2 hours/day, 3 days/week for 6-8 weeks at a high or low rate. Reach rate and abnormal movement patterns were recorded. Serum was collected at 6 and 8 weeks for ELISA assay of IL-1α and IL-1β. High repetition animals experienced a 2-fold decline in reach rate, strong emergence of a raking movement, and increased IL-lα. IL-lα decreased in the low repetition group. IL-lβ decreased in both groups. This model provides evidence that inflammation increases with repetition. At the higher reach rate, persistent IL-lα serum levels indicate chronic inflammation that is attenuated at the lower reach rate. These findings support the use of risk reduction in MSD prevention.

    MEDICAL SYSTEMS AND REHABILITATION: Medical Systems and Rehabilitation Posters

    Usability of Emergency Medical Devices: Assessment and Design Implications BIBAFull-Text 1491-1495
      Jennifer Fisher; Beth Loring
    The goal of this study was to assess the usability of portable electronic emergency medical equipment. The study consisted of field interviews conducted with emergency medical workers, including emergency medical technicians (EMTs), paramedics, and firefighters. We sampled a varied population, including workers from urban and suburban areas as well as private and public organizations. Equipment manufacturers can use the results of this study to enhance the usability, efficiency, and acceptability of future emergency medical devices.
    Beliefs and Potential Use of Prescription Drug Information Sources BIBAFull-Text 1496-1500
      Kevin E. Hicks; Michael S. Wogalter
    In recent years consumers are taking more interest in their health care, including having interest in the prescription drugs they take. This research examined people's beliefs and perceptions about using nine sources of prescription drug information. The sources investigated were: (a) physician, (b) pharmacist, (c) family or friend, (d) manufacturer's web site, (e) second-party web sites, (f) medical reference book, (g) manufacturer's consumer phone number, (h) print ads, and (i) television ads. Two hundred thirteen persons were asked to make ratings of these sources according to (1) the likelihood that they would use each source, (2) perceived ease of use to obtain information from each source, and (3) how complete the information would be in providing prescription drug information. The results indicate that the pharmacist and physician sources were in general given significantly higher ratings across all of three dimensions than all the other sources. The two next highly rated sources were family or friend and manufacturer's web site. Television and print ads were rated the lowest among all of the sources. Implications of these results are discussed with emphasis on the Internet as a growing source of prescription drug information.
    Combat Medicine: A Model for Civilian Mass Casualty Managment BIBAFull-Text 1501-1505
      John P. Holmquist; John S. Barnett
    Casualty management is vital in combat. Prior to World War I, the wounded soldier's outlook for survival was dismal. However, technological advances of the twentieth-century introduced combat medics, triage, and improved medicines to the front lines, as well as, paramedics, 9-1-1 response, and state and local emergency centers on the home front, reducing pain and saving lives. Emerging technology promises to bring further life-saving techniques to the future battlefield and civilian disasters. With the advent of digital networks and sophisticated information technology, the ability to assist the wounded and evacuate casualties from the combat zone and city emergency areas promises tremendous improvements in casualty management and subsequent patient survival. This paper provides a brief review of the evolution of battlefield medicine and extrapolates how combining applied human factors with emergent digital technology could enhance battlefield and disaster casualty management.
    Monitor-Position in Laparoscopic Surgery BIBAFull-Text 1506-1510
      U. Matern; K. Kehl; C. Giebmeyer; M. Faist
    One of the key problems in laparoscopy is the correct positioning of the monitor. In this study we tested task performance and muscle-strain of subjects in relation to monitor-position during laparoscopic surgery. 18 subjects simulated laparoscopic suturing. This was repeated in three monitor positions (15 minutes each) frontal at eye level (A), frontal in height of the operating field (B) and 45° to the right side at eye level (C). No head movements were allowed during a single session. In a fourth measurement the subjects were allowed to move the head and to look at any monitor. After the test they were asked for their preferred monitor position. During all tests the electromyographic (EMG) activity of six main neck muscles was recorded and the number of pearls was counted. The EMG activity was significantly (p<0.05) lower for position A compared to position B or C. No significant difference was found between the positions B and C. The number of threaded pearls as an indicator for task performance was highest for position B. The difference was statistically significant compared to position C but not between positions A and C or A and B. Asked for the preferred monitor position 9 subjects chose two monitors in the frontal positions A and B. No subject preferred the monitor at the side (C).
       Regarding EMG data the monitor positioned frontal at eye level is preferable. Reflecting personal preferences of subjects and task performance it should be of advantage to place two monitors for the surgeon: one in position A for lowest neck strain, and the other one in position B for difficult tasks with optimal task performance. The monitor position at the side is not advisable.
    Emergency Physician to Admitting Physician Handovers: An Exploratory Study BIBAFull-Text 1511-1515
      Amy L. Matthews; Craig M. Harvey; Richard J. Schuster; Francis T. Durso
    Current emphasis on the number of deaths due to medical errors has pushed the patient safety issue to the forefront at many medical institutions. The Institute of Medicine's recommendation for improved coordination and collaboration between physicians, as well as the paucity of related literature, has led the authors to explore the nature of the handover between emergency department and admitting physicians.
       Research was conducted at two Ohio hospitals to document the phases and issues found in emergency department (ED) handovers. The phases for ED handovers were similar to those found in shift changes in other types of industries (e.g., paper mill, air traffic control) with minor variations in the order of the phases. Three areas were identified where potential errors could occur including the spoken communication between physicians, selection of diagnostic tests based on the specific admitting physician, and the use of surrogates by the admitting physician. Physicians identified the level of trust in ED resident physicians, incomplete handovers between ED physicians at their shift change, differences in exams and treatment plans based on admitting physician, and notification of possible admission prior to receiving results for exams as potential problem areas.
       The findings of this research illustrate the need for future research into physician communication. These studies have tremendous opportunity to enable the Institute of Medicine's goal of improving communication between physicians for better patient care and outcomes.
    Combining Experts and Video Clips: Ergonomic Analysis for Safer Medical-Instrument Trays BIBAFull-Text 1516-1520
      F. Jacob Seagull; Colin Mackenzie; Marilyn Sue Bogner; Anju Sidhu; Ross Davis; Yan Xiao
    Identifying systems problems is essential in improving patient safety. The field of human factors has established many methodologies for identifying and resolving systems problems. In this paper, we use the case of instrument trays for chest-tube placement to illustrate a human factors methodology in identifying systems problems. A questionnaire was developed to solicit problems associated with chest-tube trays. Reported problems included accidental injuries to operators, such as needle sticks. Short video clips from 49 chest-tube placements were shown to subject matter experts, who also filled in a questionnaire about their opinions on chest-tube trays. Three types of problems were identified with chest-tube trays that may lead to injuries to the operator and/or harm to the patient: the position, constellation, and content of the chest-tube tray. Using expert reviews of video clips helped identify systems problems associated with instrument trays. We believe that videos can complement the current design practices of expert consensus.
    The Effects of Ergonomic Desk with Regard to Motor Accuracy in the Writing Performance of the Students with Cerebral Palsy BIBAFull-Text 1521-1525
      I-hsuan Shen; Sue-may Kang; Ching-yi Wu
    This study was conducted to examine the effects of ergonomic desk design for improving motor accuracy in the writing performance of cerebral palsy students. Thirty-two cerebral palsy students were tested in four workstations. Work surface design involved a regular work surface and a cut-out work surface, and desk angle design included a horizontal desk top and a 20° inclined desktop. The height of the desk and chair were adjustable. We compared the writing performance of each subject by administering the Motor Accuracy Test. The writing performance was obtained by accuracy score and adjusted score. Results showed that accuracy score didn't reach the significant level (p=0.0593); however, adjusted score was significantly (p<0.05) better at the cutout table than at the regular table. And students with athetoid benefited from the cutout surface significantly. These results indicated that a cutout work surface elicited significantly better tracing performance than a regular work surface did.
    Trends in Workplace Changes: Follow-Up of Job Analyses BIBAFull-Text 1526-1530
      Kristin Streilein; Sheryl Ulin; Thomas Armstrong
    Ergonomic job analysis is considered to be a primary step in preventing work disability related to musculoskeletal problems. There has been little work examining what ergonomic changes are actually occurring after an ergonomic job analysis. This paper looks at what types of workplace changes are being implemented and what if any trends exist in these changes. It was found that in the manufacturing setting, workers were more likely to change jobs and workplace changes occurred with line changes rather than as an accommodation for a particular employee. In the office setting, ad hoc individualized changes to workstations were used in an effort to accommodate workers in their current jobs.

    PERCEPTION AND PERFORMANCE: Vigilance and Workload [Lecture]

    Vigilance, Workload, and Boredom: Two Competing Models BIBAFull-Text 1531-1535
      Caroline R. Alikonis; Joel S. Warm; Gerald Matthews; William N. Dember; Edward M. Hitchcock; James J. Kellaris
    Two models that seek to explain the high workload associated with vigilance tasks are the direct-cost and indirect-cost views. The former attributes the elevated workload to the high information-processing demand of the task; the latter attributes it to efforts to combat the boredom associated with monotonous vigilance tasks. A recent study by Hitchcock et al. (1999) provided support for the direct-cost view by showing that it is possible to lower the workload of vigilance through reductions in the information-processing load while leaving task-induced boredom unaffected. This study provides converging evidence for the direct-cost view: allowing observers to listen to a stress-reducing musical selection, Heart Zones, during a vigil lowered boredom while leaving the perceived workload of the task unaffected. The beneficial effect of the musical selection was limited to boredom; it had no impact upon post-vigil feelings of loss of task engagement and distress.
    Workload and Stress of Configural Displays in Vigilance Tasks BIBAFull-Text 1536-1540
      James L. Szalma
    The workload and stress associated with configural displays in two vigilance tasks were investigated. Two kinds of configural displays were employed: A bar graph display and an object display. A non-configural bar graph display served as a control group. Relative to the non-configural display, both configural displays improved performance in a task requiring integration of information, but were not significantly different from the control group in a task requiring focused attention to display elements. The object display reduced workload in both tasks, but the bar graph configural display did not. Results showed a complex pattern of association/dissociation of workload with performance. Self reports of stress revealed that the tasks were stressful but that configural displays did not reduce the stress of either task.
    Target Acquisition With UAVs: Vigilance Displays and Advanced Cueing Interfaces BIBAFull-Text 1541-1545
      Daniel V. Gunn; W. Todd Nelson; Robert S. Bolia; Joel S. Warm; Donald A. Schumsky; Kevin J. Corcoran
    Future Uninhabited Aerial Vehicles (UAVs) will require operators to switch quickly and efficiently from supervisory to manual control. Utilizing a vigilance task in which threat detections (critical signals) led observers to perform a subsequent manual target acquisition task, the present investigation revealed that the type of vigilance display might have important design implications for future UAV systems. A sensory display format resulted in more threat detections, fewer false alarms, and faster target acquisition times and imposed a lighter workload than a cognitive display format. Thus, the former may be the best display arrangement for future UAV controllers. Additionally, advanced visual, spatial audio, and haptic cueing interfaces enhanced acquisition performance over no cueing in the target acquisition phase of the task, and did so to a similar degree. This finding suggests that advanced cueing interfaces may also prove useful in future UAV systems and that these interfaces are functionally interchangeable.
    Further Tests of an Abbreviated Vigilance Task: Effects of Signal Salience and Jet Aircraft Noise on Performance and Stress BIBAFull-Text 1546-1550
      William S. Helton; Joel S. Warm; Gerald Matthews; Kevin J. Corcoran; William N. Dember
    The effects of signal salience and jet-aircraft noise on performance and self-reports of stress were examined in an abbreviated vigilance task (12 min) that duplicates many of the findings with longer duration vigilance tasks (Temple et al., 2000). As is the case with longer vigils, signal detection in the abbreviated task was poorer for low salience than for high salience signals and stress scores, as indexed by the Dundee Stress State Questionnaire (Matthews, Joiner, Gilliland, Campbell, & Falconer, 1999), were generally greater when observers were required to detect low as compared to high salience signals. Unlike longer vigils, however, signal detection in the abbreviated task was superior in the presence of noise than in quiet, and noise generally attenuated self-reports of stress. The beneficial effect of jet-aircraft noise for the abbreviated task differentiates it from longer vigilance tasks and suggests that noise may have short-term positive value in vigilance.

    PERCEPTION AND PERFORMANCE: Motion and 3D [Lecture]

    Kinesthetic Compensation for Misalignment of Teleoperator Controls through Cross-Modal Transfer of Movement Coordinates BIBAFull-Text 1551-1555
      Stephen R. Ellis; Bernard D. Adelstein; Robert B. Welch
    When a teleoperation system's remote image sensor is oriented so as to misalign the display coordinates in which the user must operate, control difficulties arise. Users then must learn to compensate for a rotational sensorimotor rearrangement. A new compensation technique is proposed in which the hand not used for control provides a kinesthetic cue to the rotation. In essence, the cueing hand provides a kinesthetic reference for the movement of the controlling hand. Users then make their control movements relative to their kinesthetic sense of the cueing hand's orientation. Experiments show that this technique can reduce control disturbances for some misalignments by up to 64%.
    The Horizontal-Vertical Velocity Illusion: Implications for the Design of Dynamic Displays BIBAFull-Text 1556-1559
      Nathan R. Bailey; Mark W. Scerbo
    It has long been known that physically equivalent vertical and horizontal stimuli are often perceived as different. The present study examines this phenomenon in the context of motion perception. Participants were asked to judge the speed of stimuli moving in vertical and horizontal directions using the method of constant stimuli. The findings are consistent with previous research in that vertically moving stimuli appear to move relatively faster than horizontal stimuli traveling at the same speed. Further, the axis of focus, i.e., horizontal or vertical, used as the standard for comparison of the two relative velocities, appears to mediate the perceived velocity of the vertically ascending and vertically descending stimuli. These findings may have important implications for the design and implementation of displays that use a combination of both horizontal and vertical indicators.
    Use and Misuse of Linear Perspective in the Perceptual Reconstruction of 3-D Perspective View Displays BIBAFull-Text 1560-1564
      Harvey S. Smallman; Mark St. John; Michael B. Cowen
    Despite the increasing prevalence of three-dimensional (3-D) perspective views of scenes, there remain a number of concerns about their utility, particularly for precise relative position tasks. Here, we empirically measure and then mathematically model the perceptual biases found in participants' perceptual reconstruction of perspective views. Participants reconstructed the length of 10 test posts scattered across a 3-D scene to match the physical length of a reference post. The test posts were all oriented in the X, Y or Z cardinal directions of 3-D space. Four viewing angles from 90 degrees ("2-D") down to 22.5 degrees ("3-D") were used. Matches systematically underestimated the compression of distances into the scene (Y) and systematically overestimated the compression of height (Z). A simple computational model is developed to account for the results that posits that linear perspective (that only operates in X) is inappropriately used to scale matching lengths in all three dimensions of space. The model suggests a novel account of the systematic underestimation of egocentric distances in the real world.
    Judgments of 3D Bars in Depth BIBAFull-Text 1565-1569
      J. G. Hollands; Heather A. Parker; Andrew Morton
    Twenty participants judged the relative size of two bars portrayed at different locations in a 3D bar graph. Bars were co-located, placed side by side (near adjacent), or the small bar occluded the large (near or far occluded). Error was greater for the far occluded condition and there was greater variability in bias scores. To account for observed error, we proposed a model that distinguishes between cyclical bias commonly observed in proportion judgments and bias resulting from improper size-distance scaling. The model was fit to data, and the results indicated that the absolute value of size-distance scaling parameter γ was greater in the far occluded condition. Inclusion of γ increased R2 for far and near occluded conditions only. Bar location did not affect cyclical bias. Thus, judgments of the relative sizes of bars in 3D bar graphs showed increased error when the bars were separated, due to inaccurate size-distance scaling.
    Effects of 3D Auditory Display on Dual Task Performance in a Simulated Multiscreen Watchstation Environment BIBAFull-Text 1570-1573
      Derek Brock; Janet L. Stroup; James A. Ballas
    It is anticipated that watchstation operators in future U. S. Navy command and control environments will work in multitask settings that raise substantial performance and attention management challenges for user interfaces. To evaluate the capacity of an auditory display to contribute to the resolution of these concerns, we constructed a mockup of the Navy's current advanced multi-modal watchstation design and conducted a dual-task experiment that manipulated the visual distance between the task displays and the use of spatialized sound to direct attention (auditory deixis). Subjects in the repeated measures design were asked to carry out a continuous tracking task and a tactical decision task at the same time. Deictic sound had significant, positive effects on subjects' performance on the tactical task -- response times were improved and there were fewer head movements. Furthermore, these benefits were achieved with no loss in tactical decision accuracy and no degradation in performance on the tracking task.

    PERCEPTION AND PERFORMANCE: Displays and Controls I [Lecture]

    Sonification Design for Real-Time Processes: Issues and a Demonstration. BIBAFull-Text 1574-1578
      Janet Anderson; Penelope Sanderson
    While interest is growing in the possible advantages of sonifiying physiological information in the operating room, principles to guide the design of sonifications have not been fully developed. An unresolved question concerns the number of auditory streams that can be monitored and the number of auditory dimensions carrying information within a stream that can be monitored. This question has implications for the effective operation of selective and divided attention. This experiment explored the perceptual limits of attending to six acoustic parameters of one sound stream. A range of discriminable differences was developed for each of six acoustic parameters. Performance on a discrimination task for all six acoustic parameters was significantly different from chance when only one acoustic parameter changed. Performance levels significantly different from chance were obtained for five of the six acoustic parameters when one other distractor parameter also changed. However, performance dropped to below chance for all parameters when five distractor parameters also changed. The results are discussed in the context of ongoing research that approaches the design problem from both a perceptual perspective and a cognitive, strategic perspective.
    Perception of Sonified Daily Weather Records BIBAFull-Text 1579-1583
      John H. Flowers; Douglas C. Grafel
    Human participants performed a perceptual task in which they sorted auditory (musical) displays of one-month long daily weather summaries (temperature, rainfall, and snowfall) based on perceived similarity of weather patterns. Displays for fifteen winter months and fifteen summer months were sorted by separate groups of participants. Each group sorted two sets of displays that varied in presentation speed. Multidimensional scaling analyses indicated that these displays were effective in conveying weather features important for climate comparisons for both winter and summer months, and that the faster (7.1 sec) displays were more effective than the slower (14.2 sec) displays. These results show that sonification can be an effective tool for exploring multivariate time series data, but that optimization of such displays may require consideration of the temporal constraints of auditory sensory memory and working memory.
    Collective Mistrust of Alarms BIBAFull-Text 1584-1588
      James P. Bliss; Laticia Bowens; Rebecca Krefting; Ashley Byler; Anastasia Gibson
    Recently, alarm systems have become more sensitive and ubiquitous. Unfortunately, sensitive alarm systems may produce greater numbers of false alarms, lowering an operator's level of trust and degrading task performance. In the past, researchers have considered only situations where individuals react to alarms. Because of the frequency and variability of teamed alarm reaction scenarios, we investigated the reactions of independent and dependent teams to marginally reliable alarms. Based on prior literature, we expected dependent teams to show slower but more appropriate alarm reactions and poorer ongoing task performances. One hundred four general psychology students (52 two-person teams) independently or dependently performed a psychomotor task while reacting to alarms that were 30%, 50%, or 70% reliable. Participants responded more frequently to alarms of higher reliability, and less appropriately to those of medium reliability. Generally, dependent teams made more appropriate alarm reactions. Our results suggest that designers and trainers should promote team interdependence when operators are faced with marginally reliable signals.
    Varying Color Intensity to Represent Time Decay in Visual Icons BIBAFull-Text 1589-1593
      Patrick K. McGinty; Shannon R. Worthan; Michael D. Matthews
    The U.S. Army is developing a number of digital command and control systems that convey complicated information through the use of visual icons. The purpose of the current research was to test a method to identify time lapses in the display of such information. Eighteen U.S. Military Academy cadets enrolled in a general psychology course volunteered to participant in the experiment. Using a between groups design, the participants were assigned to one of three groups. Each group was tested with three, four, or five color intensities of icons and the time and accuracy of responses were recorded. The results indicated that the number of color intensities used to code elapsed time in a visual icon affected identification time, with five color intensities resulting in significantly longer detection times than when three color intensities were used. There was no significant difference among the three groups is accuracy of responses. Implications for the display of time-sensitive information on command and control systems are discussed.
    Effects of a Virtual Air Speed Error Indicator on Guidance Accuracy and Eye Movement Control During Simulated Flight BIBAFull-Text 1594-1598
      William A. Schaudt; Kristin J. Caufield; Brian P. Dyre
    We examined whether flight-control performance might be improved by presenting airspeed information to peripheral areas of the visual field using virtual head-up displays (HUDs), and whether participants process these displays using peripheral, rather than central, vision. We found that, compared to a standard HUD speed indicator, a peripherally located virtual speed indicator produced superior altitude control and equivalent or better speed control. Participants' gaze dwell times were more concentrated on flight-path and altitude control information as compared to speed information for the virtual HUD speed indicator. Gaze patterns showed that participants processed the virtual speed indicator with peripheral vision while they needed to directly fixate the traditional military standard HUD speed indicator in central vision. We believe the virtual display allowed participants to acquire speed information in a manner consistent with naturally-evolved orienting processes and therefore reduced central visual field load, attentional demand, and overall mental workload, freeing resources for better flight-path control.

    PERCEPTION AND PERFORMANCE: Search and Attention [Lecture]

    Effects of Symbol Brightness Cueing on Attention During a Visual Search of a Cockpit Display of Traffic Information BIBAFull-Text 1599-1603
      Walter W. Johnson; Min-Ju Liao; Stacie Granada
    This study investigated visual search performance for target aircraft symbols on a Cockpit Display of Traffic Information (CDTI). Of primary interest was the influence of target brightness (intensity) and highlighting validity (search directions) on the ability to detect a target aircraft among distractor aircraft. Target aircraft were distinguished by an airspace course that conflicted with Ownship (that is, the participant's aircraft). The display could present all (homogenous) bright aircraft, all (homogenous) dim aircraft, or mixed bright and dim aircraft, with the target aircraft being either bright or dim. In the mixed intensity condition, participants may or may not have been instructed whether the target aircraft was bright or dim. Results indicated that highlighting validity facilitated better detection times. However, instead of bright targets being detected faster, dim targets were found to be detected more slowly in the mixed intensity display than in the homogenous display. This relative slowness may be due to a delay in confirming the dim aircraft to be a target when it was among brighter distractor aircraft. This hypothesis will be tested in future research.
    Partitioning Visual Displays: Directing the Path of Visual Search BIBAFull-Text 1604-1608
      Craig Haimson; John R. Anderson
    We reduced time to detect target symbols in mock radar screens by partitioning displays in accordance with task instructions. Targets appeared among distractor symbols either close to or far from the display center, and participants were instructed to find the target closest to the center. Search time increased with both number of distractors and distance of target from center, and the effect of distractors was considerably greater for far than close targets. However, when close and far regions were delineated by a centrally-presented "range ring", the distractor effect was substantially reduced, especially for far targets. We suggest that range rings focus attention on specific regions of the screen and aid in the determining of which regions have already been searched.
    Directing Attention in Open Scenes BIBAFull-Text 1609-1612
      Stephen Hughes; Michael Lewis
    Attention direction is particularly difficult in open scenes such as detailed aerial photographs, wide angle/multiple video feeds, or high-resolution digital imagery. Unlike conventional displays that have single parameters with definable set points, open scenes lack easy criteria for directing attention. The present study investigates the effects of varying levels of highlighting for correctly and incorrectly designated targets. The results suggest that linking the intensity of highlighting to degree of confidence may be an effective display strategy to maximize efforts to draw attention to objects in an open scene.
    The Effects of Visual Cues and Interstimulus Interval on Accuracy in Auditory Localization and Detection. BIBAFull-Text 1613-1617
      Joseph T. Coyne; Mark D. Lee; Pitney Bowes
    Auditory localization is an increasingly important topic as the technology for audio displays is becoming more available. However, few studies examine the effects of multiple simultaneous distracters on auditory detection and localization performance. Previous research has found that detection and localization performance significantly drop as the number of distracters increases; however, it is not clear what causes these errors. In the present study, participants either had to localize an auditory stimulus or detect an auditory stimulus among multiple distracters. Similar to previous research the number of errors significantly increased as the number of active speakers increased. Also consistent with previous research, the detection performance was better than the localization performance. The use of visual cues was found to benefit the localization group but did not significantly affect performance in the detection group. The present study also found that a longer interstimulus interval improved accuracy only in the localization group, and then only when visual cues were present. These findings provide insight into the complex nature of the auditory search task.
    Sound Localization With Hearing Protectors: Performance and Head Motion Analysis in a Visual Search Task BIBAFull-Text 1618-1622
      Brian D. Simpson; Robert S. Bolia; Richard L. McKinley; Douglas S. Brungart
    The effects of hearing protection on sound localization were examined in the context of an auditory-cued visual search task. Participants were required to locate a visual target in a field of 5, 20, or 50 visual distractors randomly distributed throughout ±180° of azimuth and from approximately -70° to +90° in elevation. Four conditions were examined in which an auditory cue, spatially co-located with the visual target, was presented. In these conditions, participants wore (1) earplugs, (2) earmuffs, (3) both earplugs and earmuffs, or (4) no hearing protection. In addition, a control condition was examined in which no auditory cue was provided. Visual search times and head motion data suggest that the degree to which localization cues are disrupted with hearing protection devices varies with the type of device worn. Moreover, when both earplugs and earmuffs are worn, search times approach those found with no auditory cue, suggesting that sound localization cues are nearly completely eliminated in this condition.

    PERCEPTION AND PERFORMANCE: Displays and Controls II [Lecture]

    Effect of History Trail Display on Human Spatial Performance under Normal and Rotated Spatial Mappings BIBAFull-Text 1623-1627
      Weiwei Du; Paul Milgram
    In a rotated visual-motor mapping environment, human spatial performance is seriously affected by misaligned visual and motor reference axes, resulting in elevated spatial errors. In this paper, we propose a history trail display in an augmented reality setting. We investigate the effectiveness of the display in consecutive aiming tasks, under normal visual-motor mapping, as well as mappings with 90°, 135°, and 180° rotations. Spatial movement error and the smoothness of the trajectories were measured and compared between the history trail display and the regular video display. Our results show that, under normal mapping condition, the history trail appears to help reduce the spatial movement error and improve the smoothness of the movement trajectories. With rotated mappings, the benefit of the history trail becomes significant only after a certain degree of adaptation to the rotated mappings has been attained. The history trail appears to enhance the perception of errors, movement direction, and speed information for error-correcting processes during the aiming movements.
    Intrinsic Reference Systems in Map Displays BIBAFull-Text 1628-1632
      Steffen Werner; Melanie Jaeger
    Within the area of navigation displays, the distinction between track-up display and fixed-orientation displays (north-up) has received a lot of attention. Theoretically, this distinction has been linked to different spatial frames of reference. Using alignment effects, recent studies on the role of different reference systems in human spatial memory have identified the important role of environmental and intrinsic reference systems for the cognitive organization of spatial information. In the first experiment of its kind, we tested the effects of alignment of an observer with the visible, local environment and the global, large-scale environment depicted in a You-are-Here type of map display while holding the usually emphasized relation between map orientation and observer orientation constant. Our results show that both alignments have a strong and additive effect on memory performance, suggesting a new and important dimension for the design of spatial information displays such as maps.
    Reading Vertical Text: Rotated vs. Marquee BIBAFull-Text 1633-1635
      Michael D. Byrne
    There are numerous design situations in which it impossible to present English text in its normal horizontal orientation. There are multiple options available when text must be presented vertically: rotating horizontal text 90° to the left or to the right, or in a downward cascade of letters such as on a theater marquee. While it seems intuitive that horizontal text will be recognized faster than vertical text, which presentation format is best for vertical text? An experiment was conducted to investigate, and found that marquee text is indeed read more slowly than rotated text, and that rotated text is read more slowly than standard horizontal text. However, no evidence was found for a difference between left- and right-rotated text. Word frequency effects were larger in all vertical conditions relative to the horizontal control. These results suggest that rotated text is generally to be preferred to marquee-style presentation.
    Visual and Postural Constraints in Coordinated Movements of the Head in Hand Reaching Tasks BIBAFull-Text 1636-1640
      K. Han Kim; Bernard J. Martin
    The purpose of the present study is to investigate movements of the head spatially and temporally coordinated with hand reach movements simulating industrial assembly tasks. The motions recorded from thirty subjects performing reach movements with the right hand toward eccentric targets indicate that 1) hand movement onset lags head movement onset with a duration proportional to target eccentricity; 2) the head does not aim directly at a target, but travels only a fraction of target eccentricity and often deviates away from the target substantially; and 3) head movements are constrained by the strategy of either controlling the head position in space or controlling head rotation about the torso. These results indicate that head movements are constrained by both visual and non-visual factors. While the major function of the head is to displace the visual gaze toward the target, non-visual constraints, which include postural coordination with whole body movements, also significantly affect head movements.
    Representing Complex Data Sets as Virtual Structures BIBAFull-Text 1641-1644
      Adam R. Richardson; Marvin J. Dainoff; Leonard S. Mark; James L. Smart; Niles Davis
    This paper describes a research strategy in which complex data sets are represented as physical objects in a virtual 3-D environment. The advantage of such a representation is that it allows the observer to actively explore the virtual environment so that potential ambiguities found in typical 3-D projections could be resolved by the transformation resulting from the change in viewing perspective. The study reported here constitutes an initial condition in which subjects compared relative size of virtual cubes from two different viewpoints. These results can serve as a basis for construction of cube-like objects representing the underlying conceptual structure of a data set.

    PERCEPTION AND PERFORMANCE: Perception and Performance Posters

    Change Detection on Periphery and Dual-Task Performance BIBAFull-Text 1645-1648
      Mon-Chu Chen; Filipe Fortes; Roberta Klatzky; William Long
    A variation of the Wickens' Task was performed to examine the assumption that people can detect certain stimuli on their periphery without decreasing the performance of the primary task. Participants were instructed to respond to a change in a peripheral stimulus without shifting their gaze from a primary task in the center of their visual field. Our data suggests that both type and magnitude of change have a significant effect on detection rate and reaction time. The data also suggests that the performance of the primary task did not decay after the change of the stimuli occurred. Based on these findings, we argue that people can detect various types of changes without shifting gaze and without degrading task performance. Therefore, an interface particularly designed for peripheral vision is possible, and it will potentially provide benefits to both productivity and safety.
    Judgments about Collisions in Simulations of Scenes with Textured Surfaces and Self-Motion: Do Display Enhancements Affect Performance BIBAFull-Text 1649-1653
      Patricia R. DeLucia; Les E. Meyer; Jason M. Bush
    To move through the environment safely, people must make effective judgments about collisions. It has been asserted that most studies of time-to-collision judgments are limited due to a lack of visual realism (Manser & Hancock, 1996). Studies that compared performance among displays which differed in realism provided mixed results. We measured judgments about whether, and when, two objects would have collided with each other. Results from simulations of scenes with colored, textured surfaces and a moving observer were mostly comparable to earlier results from simulations of black-and-white, line-drawn objects and a stationary observer (DeLucia, 1995; DeLucia & Meyer, 1999). Texture and self-motion affected performance in a restricted set of conditions and did not eliminate errors due to misleading depth cues. Increases in realism, which incur more costs and computational time, may not always be justifiable from a performance standpoint. Results have design implications for simulators and virtual reality systems.
    Effects of Signal Regularity and Salience on Vigilance Performance and Cerebral Hemovelocity BIBAFull-Text 1654-1658
      Todd D. Hollander; Joel S. Warm; Gerald R. Matthews; William N. Dember; Raja Parasuraman; Edward M. Hitchcock; Christina A. Beam; Lloyd D. Tripp
    The signal regularity effect -- enhanced performance efficiency when critical signals for detection appear in a temporally regular as opposed to an irregular manner, has a long history in vigilance research. However, the precise conditions under which this effect can be elicited have not been identified. Toward that end, this study demonstrates that the effect is limited to low salience signals, perhaps because the effort needed to generate veridical temporal expectancies is unnecessary with high salience signals. Additionally, using signal detection theory indices (d' & c) and neuroimaging of cerebral blood flow via transcranial Doppler sonography, this study also shows that the signal regularity effect is rooted in sensing rather than decision-making factors and that it is localized in the right cerebral hemisphere.
    A Simple Tool for Predicting the Readability of a Monitor BIBAFull-Text 1659-1663
      William K. Krebs; Jing Xing; Albert J. Ahumada
    Background: Human factor practitioners are sometimes required to provide an immediate answer to an acquisition question, e.g., what is the readability of this monitor? Unfortunately, readability is not listed on the manufacturer's brochure. This study proposes a simple tool to quickly assess the readability of a monitor without the need of conducting a lengthy readability study. Methods: The text readability of three observers was measured for four colors (red, green, yellow, white), three brightness (.20, .25, .45), at three locations (1.62, 2.38, 3.16 meters) on a 20' color monitor. Results: The minimum error-free readable font size could be solely determined by the text/background luminance contrast. Thus luminance, not color determined readability. From these results, a MATLAB program was developed that prompts for background and text RGB values and returns the minimal error-free readable font size. Conclusions: The tool is a fairly robust and quick predictor to assess the readability of a monitor.
    The Effects of Monocular Cues on a 3-D Target Acquisition Task BIBAFull-Text 1664-1668
      Min-Ju Liao; Walter Johnson
    This study evaluated the effects of linear perspective, droplines, and shadows on 3-D target acquisition performance. A display was presented with and without a linear perspective cue. When linear perspective was presented, it could include droplines, shadows, or both. Participants moved a cursor 'into' a target on the display as quickly and accurately as possible using a 3-D input device. Movement time and path length to acquire each target, as well as its three display dimensions (azimuth, elevation, and range), were measured. Results showed that linear perspective alone did not enhance target acquisition performance. The effects of droplines and shadows were target location dependent -- reducing movement times and path lengths to upper-front and lower-back targets by apparently facilitating range dimension acquisition. Movement trajectory analysis revealed that participants overlapped the target with the cursor and then acquired the target along the depth axis. The upper-back and lower-front targets were acquired with more direct paths than targets in other locations.
    A Computational Model of Attention/Situation Awareness BIBAFull-Text 1669-1673
      Jason S. McCarley; Christopher D. Wickens; Juliana Goh; William J. Horrey
    A computational model of attention and situation awareness (SA) was developed and used to predict pilot errors in the task of taxiing from runway to terminal. The model incorporates a low-level perception/attention module and a higher-level belief-updating module. Attentional scanning is controlled by bottom-up and top-down processes, with the effectiveness of top-down guidance varying as a function of SA. Information sampled by the low-level module is fed forward to the higher-level module for consolidation within a working memory representation of the pilot's situation, with the quality of this representation reflecting the pilot's level of SA. The model was validated by comparing its predictions to the behavior of pilots performing a taxiway simulation. Results indicate that the model successfully predicts the improved performance associated with display augmentations, and provides construct validity regarding the effects of visibility, distraction, and degraded information quality.
    The Effects of Event Rate and Array Size on a Cognitive Vigilance Task with Associated EEG Rhythms and a Derived Engagement Index BIBAFull-Text 1674-1678
      Carl Smith; Peter Mikulka; Fred Freeman; Mark Scerbo
    This study investigated the effects of event rate and stimulus array size during a vigilance task on performance and relative EEG power bandwidths (alpha, beta, theta) and a derived EEG engagement index, El = (beta/(alpha+ theta)). Forty participants, ages 18 to 40, engaged in a visual search task. Participants were required to distinguish a green "K" from an array of stimuli (yellow-green, green, and blue-green factorially combined with K, X, N, R). Each participant searched for the signal in arrays of 2 or 5 stimuli presented at either 12 or 24 events per minute over forty minutes. The design was a 2x2 factorial with four groups. The results indicated poorer performance, higher false alarm rates in the first 10-minute period, and longer response times associated with the larger array size. There were no performance effects for event rate. The El decreased over periods. Relative alpha and beta power in the midline sites (PZ, CZ, and FZ) were greater for the higher event rate, but were unrelated to array size. These EEG findings are discussed in the context of earlier vigilance studies using EEG measures.
    Performance of Spatially and Temporally Distributed Displays as a Function of Continuous versus Discrete Update Schedules BIBAFull-Text 1679-1683
      Sherri A. Rehfeld; Dan L. Sloat; David G. Payne
    Generally, there are two ways to present monitored information: a traditional display that spatially distributes information across a screen or a temporally distributed display, which is the presentation of information serially in the center of a screen. Previous studies comparing these display formats have used methodologies in which changes in numerical information only occurred in view of the participant. This is beneficial for tight experimental control, but is not realistic since information can constantly change. The current study compared a spatially distributed display with a temporally distributed display and manipulated the updates to occur either in view, as in previous research, or continuously, even if out of view. Results showed a system response lag time in addition to participant reaction time for realistic settings and an increase in missed events not shown in previous research. These findings suggest that while a temporally distributed display is currently far from implementation, research shows promise for this technology.
    Legibility of Words Rendered using ClearType BIBAFull-Text 1684-1687
      Thomas R. Aten; Leo Gugerty; Richard A. Tyrrell
    ClearType is a software technique that uses sub-pixel addressing in an effort to increase the readability of digitized text. To evaluate whether ClearType improves the legibility of words relative to aliased text, 24 students performed a lexical decision task that involved brief exposures to 280 words and 280 non-words at different retinal eccentricities. Participants were significantly more accurate at identifying words with ClearType than without ClearType. Accuracy was also higher with non-italicized text and when the text was centered around the fixation point. Response times did not significantly vary across these same variables. Thus ClearType offers a significant improvement in word legibility while not adding to the cost of display hardware.
    Motion in Mimic Displays: Effects on the Detection and Diagnosis of Electrical Power System Failures BIBAFull-Text 1688-1692
      Douglas A. Wiegmann; Gavin R. Essenberg; Thomas J. Overbye; Aaron M. Rich
    New power system displays have been developed to aid operators in the detection and diagnosis of faults. The enhancement of integrated one-line diagrams of power system data with motion and motion cues was examined in this experiment. Participants acknowledged and solved power system failures on a simulated power network across a number of trials of varying complexity. Participants performed these tasks using interactive displays indicating power flow with digits, stationary arrows, or moving arrows. For high complexity scenarios, results indicated a general advantage for the motion display in the diagnostic task (problem resolution) but a slight advantage of the digital display on the fault detection task (problem identification). Performance with the stationary arrow display was generally between the other two groups, being nearly as good as with the digital display in the detection task and nearly as good as with the moving arrow display in the diagnosis task. Further research is necessary to determine the conditions where motion is most beneficial.

    PROFESSIONAL DEVELOPMENT: Articles

    HFE's Place in the Parade: Should We Be Drum Majors or Toot our Own Horns BIBAFull-Text 1693-1696
      Robert A. North; Christopher Miller; Valerie Gawron; Anna Wichansky; Barry Beith; Sherry Chappell; Arnold Lund; Robert North
    A debate among the Human Factors and Ergonomics Society's membership concerns the best method for increasing the disciplines prominence and influence in the design of human-centered systems. At last year's Annual Meeting in Minneapolis, President William Howell gave a perspective on the two schools of thought -- (1) the Unique Discipline model and (2) the Shared Philosophy model. In this panel discussion, several members of the management community that lead groups practicing HFE were asked to share their experiences on their successes and barriers in moving HFE to positions of influence in product design.

    SAFETY: Warnings and Risk Perception [Lecture]

    Masked Thresholds and Predicting the Audibility of Auditory Displays: An Example for Long-Haul Trucks BIBAFull-Text 1697-1701
      John G. Casali; Gary S. Robinson; Suzanne E. Lee
    Noise is an unfortunate by-product of our modern industrial society, with effects ranging from minor annoyance, to major risk of hearing damage, to inability to hear warnings and other signals. This paper presents an extensive observational study of the methodology aimed at predicting the audibility of auditory displays and warnings. While the details of the discussion relate specifically to long-haul truck-cab environments, the procedures are generally applicable to any instance where it is necessary for an individual to hear intentional or incidental sounds. The discussion includes spectral measurements of both the background noise and signals, calculation of masked threshold per ISO 7731:1986(E), and analytical comparison of signal spectra to masked thresholds to determine signal audibility. A specific example calculating the audibility of train horns in the truck cab environment is then presented. Recommendations for improving the audibility of signals in noisy environments are also provided.
    Perceptions of Vehicle Driver Safety by Cellular Phone Owners and Non-Owners BIBAFull-Text 1702
      Eric F. Shaver; Michael S. Wogalter
    Innovations in wireless technology have made cellular telecommunications inexpensive and pervasive. The ability to communicate with others virtually anywhere has benefits in terms of productivity and sociability and in some cases safety. However, cellular phone use while operating a vehicle has been implicated in increasing the likelihood of accidents. Recent research suggests that use of cellular phones while driving may quadruple the risk of a vehicular accident (e.g., Redelmeier & Tibshirani, 1997). In the past, there has been a tendency to focus on the physical handling of the phone as the primary instigator of accidents. However, the risk may be as large or larger from high cognitive involvement and attention distraction. Part of the reason cellular phone owners use their phones while driving may be their assessability and apparent ease of use while driving. It may also be that perceptions differ between cellular phone owners and non-owners on issues pertaining to cell phone use while driving. Cellular phone owners may believe that they are able to use a cellular phone more safely when driving compared to others; a phenomenon akin to that described as optimism bias (Dalziel & Job, 1997; Dejoy, 1987). Also, it may be that cellular phone owners would be more resistant to cellular phone restrictions than non-owners.
    Inference and the Use of Similes and Metaphors in Warnings BIBAFull-Text 1703-1707
      C. Travis Bowles; Arthur D. Fisk; Wendy A. Rogers
    Warning content must be written to assure that the user knows how to apply the information at the appropriate time. Since the warning cannot provide information about all possible circumstances, in some situations individuals must make inferences about safe behavior. This paper contains two experiments that investigated compliance with warning information in situations that do and situations that do not require inferences. The first experiment, with 39 undergraduate students, tested simile use in warnings to improve compliance in inference situations. The second experiment, with 44 undergraduate students, tested metaphors in the place of the similes. In both experiments, participants were presented with products and warnings, followed by situations testing their intention to comply. Normal warnings were compared with similes (Experiment 1) and metaphors (Experiment 2). In each study, the tests required either matching information or drawing inferences. Compliance was significantly lower for situations requiring inference, for both experiments. Use of metaphors and similes to reduce inference requirements is discussed.
    Guidelines for Warnings Design: Do they Matter BIBAFull-Text 1708-1712
      Kenneth R. Laughery; Danielle L. Paige; Brenda R. Laughery; Michael S. Wogalter; Michael J. Kalsher; S. David Leonard
    A study was carried out using four measures of effectiveness to compare product warnings that are consistent with the American National Standards Institute Product Safety Signs and Labels standard (ANSI Z535.4) to warnings that are not consistent with the standard. Inconsistent warnings were based on the format of existing product warnings. Two warnings, consistent and inconsistent, for each of ten different products were evaluated: cooking oil, trampoline, paint, dresser, airbag, seat belt, tire, sports utility vehicle, reclining seat and swimming pool. The four effectiveness criteria were judgments of noticeability, likelihood to read, understandability and likelihood of complying. Participants were 176 students with varied majors from five different universities. Results indicated higher levels of judged effectiveness for the warnings that were consistent with the ANSI standard. The differences were statistically significant for all four effectiveness measures for all ten products. While warnings that are consistent with the ANSI Z535.4 standard do not by themselves necessarily constitute an adequate warning system, these results indicate that the standard does have merit and utility and represents a good starting point in warning design.

    SAFETY: Safety Potpourri [Lecture]

    The Effects of Cut-Off Length on Surface Roughness Parameters and their Correlation with Transition Friction BIBAFull-Text 1713-1717
      Wen-Ruey Chang; Mikko Hirvonen; Raoul Grongvist; William M. Aguilera
    Friction is widely used as an indicator of surface slipperiness in preventing accidents in slips and falls. Surface roughness affects friction, but it is not clear which surface roughness characteristics are better correlated with friction and, therefore, are preferred as potential interventions. The transition friction between quarry tiles and Neolite under three different mixtures of glycerol and water as contaminants was correlated with the surface parameters generated from the quarry tile surfaces. The surface roughness parameters were measured with three different cut-off lengths (0.8, 2.5 and 8 mm). The results showed that transition friction decreased as the glycerol content in the contaminant was increased due to the lubrication effect. The linear correlation coefficients between the surface roughness parameters and the measured friction increased as the cut-off length was increased from 0.8 to 8 mm. However, average of the maximum height above the mean line in each cut-off length (Rpm), arithmetical average of surface heights (Ra), mean height from third highest peak to third lowest valley in each cut-off length (R3z) and the kernel roughness depth (Rk) had the strongest correlation with transition friction across three cut-off lengths used.
    Human Error in Maritime Operations: Analyses of Accident Reports Using the Leximancer Tool BIBAFull-Text 1718-1722
      Michelle R. Grech; Tim Horberry; Andrew Smith
    This paper focuses on the problem of lack of Situation Awareness (SA) by mariners. An analysis of a large number of accident reports was conducted in order to determine the extent to which SA is a relevant issue in merchant shipping operations. For the first time use was made of the Leximancer tool due to its ability to rapidly analyse large amounts of textual information. One major function of this research was to examine the accuracy and usefulness of such a data analysis tool by comparing the results of this computer analysis with that of a 'manual' analysis (performed by two raters).
       Our results underline the importance of SA in decision-making processes in the maritime domain: a large number of investigated maritime accidents were partly due to loss of SA. Also, the results of the Leximancer tool were found to be comparable to the manual analysis, thus suggesting further use of such a system for accident report analysis in other transportation domains.
    The Impact of Shift-Work on Cognitive and Perceptual Performance BIBAFull-Text 1723-1725
      Othman Alkhouri; Steven Hall; John Wise; Marvin Smith
    The increased number of aviation accidents has triggered concerns as to the underlying causes of such accidents. Shiftwork has been discovered to be a primary contributor to many of the accidents that have occurred over the past few years. The purpose of this study was to measure the effect of fatigue on shiftworkers' cognitive and visual/perceptual performance on the first day shift, first night shift, and last night shift in the five-day workweek. The primary instrument used in this study was the Automated Performance Testing System (APTS), which contained eight various cognitive and temporal factors tests. The results indicated that performance at the end of the first night shift was significantly lower than at the end of the first day shift in the workweek, but not significantly lower than performance at the end of the last night shift in the workweek. The implications for this study could serve in better scheduling of a variety of cognitive and visual/perceptual tasks in the workplace.
    Hazardous Products in the Older Adult Home BIBAFull-Text 1726-1729
      Timothy A. Nichols; Christopher B. Mayhorn; Justin D. Whittle; Holly E. Hancock; Wendy A. Rogers; Arthur D. Fisk
    Older adults appear to be particularly susceptible to hazards in the home environment. While some studies have investigated the hazards associated with structural elements in the home environment or specific products such as throw rugs or major appliances, we used a focus group approach to investigate the full range of products with which older adults come in contact and the hazards associated with these products. We conducted six focus groups in the Atlanta area, with 6-8 older adults (age 65-80) in each group. The group discussions were guided by several key topics, including hazardous products in the home and associated hazards. Participants also completed a product usage questionnaire, establishing the representativeness of the sample, as well as providing measures of product hazard perception and product usage frequency. By assessing older adults' awareness and perceptions of hazards through a naturalistic methodology, we provide an initial step in learning how older adults adjust to hazards in the home.
    Demographic Effects of Behavior Modeling in Seat Belt Use: Analysis of 15,000 Observations BIBAFull-Text 1730-1734
      Colin G. Drury; Maria L. Drake
    Automotive seat belt use is known to be highly effective in saving lives, but is still not universally practiced, with wearing rates around 60% to 70%. A series of studies, observational and experimental has established that behavior modeling occur when vehicles have more than one occupant. More times than would be expected by chance, both occupants show the same wearing behavior. However, the demographics of this modeling effect are not clear from the literature. The current study analyzed a large database, over 15,000 observations collected in Indiana in 2001 where the sample size was large enough to provide statistical significance for even small effects. Overall, a high degree of modeling behavior was observed. Modeling was found to be larger for males and larger for the under 21 age group as drivers. Modeling was also maximized when driver and passenger belonged to the same age or gender group. Comparing drivers with and without passengers, we found that the major effect of modeling was negative, i.e. there was a large difference between drivers wearing seat belt while alone (67%) and in the presence of an unbelted passenger (18%). Implications for public policy aimed at increasing seat belt use are presented.

    SAFETY: Safety Posters

    Over-the-Counter Analgesics: A Survey of the Public's Knowledge, Attitudes and Beliefs Regarding Current Labeling Practices BIBAFull-Text 1735-1738
      Michael J. Kalsher; Michael S. Wogalter
    A wide variety of over-the-counter (OTC) medications are currently available to the general public without a prescription. Among the most popular of these are medicines termed analgesics that have pain-relieving effects. Unfortunately, many people are not aware of the significant health risks associated with their use. The main purpose of this study was to determine whether people want to be informed of these risks and whether such knowledge would influence self-reported precautionary behavior. The results showed that 92% of the 330 people surveyed wanted to be informed of the risks of OTC analgesics and nearly 95% percent agreed that this information should appear on the product label or in the materials that accompany these products. When asked about the likely actions they would take if provided with organ-specific risk information, a large majority of the respondents indicated they would take one or more precautionary behaviors to reduce the risks (e.g., take smaller dosages). A majority of respondents admitted having placed themselves at risk by taking more than the recommended dose of an OTC analgesic at one time. These results have implications for improving the quality and effectiveness of risk communications.
    A Comparison of Symbols for Preferred Behaviors BIBAFull-Text 1739-1743
      S. David Leonard
    The number of persons traveling to and working in locations where their native language is not used has increased significantly. Thus, communication via symbols has become important for many reasons, including safety. Previous research has shown that a symbol indicating that something is to be done may significantly increase understanding of symbols indicating behavior to be avoided (Leonard, 2000). The symbol indicating that an activity was permitted or to be done was the enclosure of the symbol for the activity in a pentagon. One of the present studies expanded on this result by examining the ability of individuals to learn the meaning of the symbol from a small number of presentations. The second study compared the usefulness of the pentagon symbol with another approach to presenting to do information. The pentagon was superior in drawing attention to the behavior to be performed, especially when no negative symbol was involved. Taken together the two studies provide further support for the usefulness of the pentagon symbol as an indicator of the acceptability or need to perform an activity.
    Methodological Issues in Testing Comprehension of Safety Symbols BIBAFull-Text 1744-1747
      Mary F. Lesch; Jamie R. McDevitt
    Safety symbols must be tested prior to use to ensure that they are adequately understood, as failures to communicate can result in injury or death. However, factors other than symbol quality influence assessed comprehension level: These include test method, scoring method, as well as availability of context. Open-ended and multiple-choice test methods are compared and contrasted on a number of dimensions including ease of construction, administration, and scoring. While use of an open-ended test procedure is generally recommended, it is proposed that a modified multiple-choice test, in which alternatives are assessed across multiple trials, is an attractive alternative.
    Comparison of On-Line and Physical Presentation of Product Safety Information BIBAFull-Text 1748-1752
      Emelda Santos; Marc L. Resnick
    The Internet has become a popular channel for the purchase of products. In 2001, $53 billion was spent online by U.S. consumers and $128 billion by non-U.S. consumers. However, there are few guidelines for how product safety information should be presented in on-line stores, generally leading to a lack of easily accessible information. This leads to several challenges for consumers. If no safety information is presented, consumers may choose not to purchase the product. Or they may purchase the product only to return it after reading the warnings on the physical product, or use the product and be injured. This study investigated the differences in behavior, perception, and comprehension when consumers purchased a toy for a 3-year old on-line and through the physical channel. Several differences in behavior were identified. Encouragingly, there were no significant differences in compliance, measured by the selection of age-appropriate toys, between the Internet and physical channels. However, perceptions were different. Participants were more likely to notice the warning on the Internet channel and more likely to recall and comprehend its recommendations. The results also supported previous studies that showed that users are more likely to notice, comprehend, and comply with warnings when they are presented saliently. This study extended that result to warnings presented through the Internet channel. Behavioral differences were also found. Participants relied more heavily on written product information to make their purchase choices on the Internet, perhaps because of their inability to make direct observations of the product. This highlights the critical importance of providing effective warnings online.
    Comprehension of Different Types of Prohibitive Safety Symbols with Glance Exposure BIBAFull-Text 1753-1757
      Michael S. Wogalter; LaTondra A. Murray; Barbara L. Glover; Eric F. Shaver
    The comprehension of 16 pictorial safety symbols was examined using a rapid visual exposure technique and 4 types of prohibitive circle-slash variants (over, under, partial, and translucent). Performance was higher for base pictorial images that appeared to depict more concrete, less complex and familiar concepts. Symbols were better understood with the under and translucent slashes. This research has implications for the design of pictorial symbols on roadways and in other environments where exposure to safety information may be brief.

    SPECIAL SESSION: Articles

    InfoChess: A Powerful Test Bed for Studying Information Operations (IO) Decision-Making BIBAFull-Text 1758
      William C. Elm; James W. Gualtieri; Scott S. Potter
    Participants will receive an introduction into the domain of Information Operations (IO) and asymmetric warfare. This interactive session will use InfoChess to provide experiential learning in IO and explore decision-making. By integrating IO in the rich, yet well understood game of chess, the trainee's understanding of the synergistic effects of IO and maneuver warfare is internalized to a degree not shown with traditional instruction. The audience will then be asked to collectively work together, against an asymmetrically adversary. During the course of this session, observations will be collected on the decision-making activities of the participants.

    STUDENT FORUM: Articles

    Maximizing Your Opportunities in a Competitive Job Market BIBAFull-Text 1759-1763
      Karen R. Young; Ronald G. Shapiro; Anthony D. Andre; Arnold M. Lund; Michelle M. Robertson; Ellen J. Bass; Ben-Tzion Karsh; Jia-Hua (Jim) Lin
    Welcome to the ninth annual Human Factors and Ergonomics Society Career Panel. The job market in our industry has changed significantly over the last year and the questions addressed by this year's panel speak to the issues that exist in a difficult job market. This year, the panel answered four questions to help readers prepare for a career in Human Factors and Ergonomics (HF/E), particularly in light of the current economic climate. During the HFES meeting panel session, the panel will focus on questions from the audience.

    STUDENT FORUM: Cutting-Edge Research by HFES Student Members [Lecture]

    Effects on Spatial Skills after Exposure to Low Frequency Noise BIBAFull-Text 1764-1766
      Jessica Ljungberg; Gregory Neely; Ronnie Lundstrom
    A study of spatial skills was conducted with 27 male and 27 female participants. The aim of the study was to examine the post-exposure effect of a complex low frequency noise (21 Hz) on a mental rotation task. It was hypothesised that reaction time and number of errors would increase after 20 minutes exposure to noise, and that persons exposed to more intense noise would exhibit greater impairment. Three groups of participants were exposed to a quite control condition and a noise conditions (either, 77, 81 or 86 dB (A)). After each exposure, subjects completed a mental rotation task where the stimulus consisted of one of three letters presented in five different rotations, showed either normally or mirrored. The participants were asked to respond as quickly and accurately as possible, affirmatively if the letter presented wasn't mirrored and negatively if mirrored. Statistical analysis revealed that the medium intensity level generated post-exposure effects when comparing noise and a quite condition.
    Human-Computer Interaction as Cognitive Science BIBAFull-Text 1767-1771
      Ronald Laurids Boring
    Human-computer interaction and cognitive science share historical interdisciplinary roots in human factors, but the two fields have largely diverged. Many attempts have been made to apply cognitive science to human-computer interaction, but the reverse is curiously not the case. This paper outlines ways in which human-computer interaction can serve as a unifying framework for cognitive science.
    Are there Age-Related Differences in Problem Solving on the World Wide Web BIBAFull-Text 1772-1776
      Aideen J. Stronge; Wendy A. Rogers; Arthur D. Fisk
    The present study investigated the Web-based problem solving strategies of 16 younger and 16 older experienced Web users. Participants searched for answers to 8 search tasks varying in complexity. Three questions were addressed in this study: (1) Are there age-related differences in success?, (2) If differences in success emerge, are these age-related differences quantitative (e.g., number of strategies)?, or (3) Are these age-related differences qualitative (e.g., type of strategies)?. Overall, younger adults were more successful finding the correct answer to the search tasks. However, this was not due to the number of strategies used, but instead was related to the type of strategy used. Older adults were more likely to use a top-down strategy (i.e., system tool) to find an answer to the search tasks. In general, unsuccessful searchers used significantly more top-down strategies than successful searchers. The implications for these findings are discussed.
    Comparing Audio and Tactile Inputs as Driver Attention Control BIBAFull-Text 1777-1781
      Lisbeth Almen
    In this simulator study we compared the effects that two different alerting devices had on driver attention control. The alerting devices were presented to the audio and tactile sense modality respectively. The audio alerting was in form of the driver's own name and the tactile device was in form of vibrations similar to those produced by rumble lines. While driving, the driver was distracted by a secondary task. The alerting device was then used to make the driver change his/her focus of attention back to the main task of driving. No significant difference between the alerting devices was found. A combination of the two alerting devices shows a tendency to provide the most rapid switch of attention back to focus on the main driving task. This paper is part of a study to discriminate an efficient way to alert a distracted driver so that car accidents may be reduced.

    SURFACE TRANSPORTATION: Articles

    The Intersection of Design and Human Factors in Commercial Vehicle Safety BIBAFull-Text 1782-1783
      Aaron Steinfeld; Ellen Ayoob; Timothy L. Brown; Richard Grace; Renae Bowers-Carnahan; Ronald R. Knipling
    The Federal Motor Carriers Safety Administration (FMCSA) has set a goal of reducing truck related fatalities by 50% by 2010. Achieving this goal is a formidable task requiring everyone involved in truck safety to examine his or her role as part of a coordinated effort. To this end we wish to examine the roles played by design professionals and human factors professionals in designing, implementing and evaluating advanced safety systems.

    SURFACE TRANSPORTATION: Lateral Control, Collision Avoidance, and Associated Icon Development [Lecture]

    Ergonomics in the Design of the HMI of an Advanced Driver Support System For Vehicle Lateral Control BIBAFull-Text 1784-1788
      Nicolas L; Lagoutte A; Ojeda L
    This paper describes the ergonomics studies that led to design the HMI of an advanced driver support system for vehicle lateral control. The objectives of studies presented below were, at first, to identify the characteristics of HMI corresponding to an alert for the driver and to collect first users' evaluations, then, in a second time, to assess the global system.
    Analysis of Distribution, Frequency, and Duration of Naturalistic Lane Changes BIBAFull-Text 1789-1793
      Erik C. B. Olsen; Suzanne E. Lee; Walter W. Wierwille; Michael J. Goodman
    This paper describes preliminary results of naturalistic lane change distribution, frequency, and duration data collected unobtrusively from 16 commuters using instrumented vehicles. The study was designed to improve upon previous data collection methods and support crash avoidance system development.
       A total of 8,667 lane changes (including unsuccessful maneuvers) were identified and classified in terms of severity, urgency, maneuver type, and success/magnitude. The total miles driven was 23,949 (38,542 km) with an average of 37.4 miles (60.2 km) per commute and 2.76 miles (4.44 km) per lane change. More than 37% of lane changes were due to a slow vehicle ahead. The mean duration for 7,192 single lane changes was 6.28 seconds with a standard deviation of 2.0.
       Analysis revealed no significant effects for duration. For frequency, significantly more lane changes were completed by drivers on the interstate, perhaps due to traffic density, while sedan drivers made significantly more lane changes than SUV drivers. A significant driver type (vehicle normally driven) by route (interstate or highway) interaction was discovered, perhaps due to driving style. A gender by route interaction was also found.
    The Development and Evaluation of Icons for Side Obstacle Warning Systems BIBAFull-Text 1794-1798
      Tina Brunetti Sayer
    A new class of driver assistance system under development is Side Obstacle Warning (SOW). These systems are designed to alert drivers to the presence of vehicles in adjacent lanes. Two forms of SOW systems being developed are Blind Spot Detection and Lane Change Warning. Both are relatively recent developments, and therefore have few established icons. A production test methodology was employed to develop icons that convey the functionality of the two SOW systems. Thirty drivers were asked to draw icons that conveyed the Blind Spot Detection and Lane Change Warning functions. The illustrations that resulted were categorized according to similarities, from which nine icons were developed for each Blind Spot Detection and Lane Change Warning. Sixty drivers rank ordered those icons in an appropriateness ranking test. The rank orders were analyzed, and the most promising icons for both systems are presented.
    Driver Acceptance of General vs. Specific Icons for In-Vehicle Information BIBAFull-Text 1799-1803
      Akiko Nakata; John L. Campbell; Joel B. Richman
    This study compared driver acceptance of general icons to specific icons for In-Vehicle Information System (IVIS) devices. In the study, general and paired specific icons, along with two unrelated icons, were tested in both the general and specific driving scenarios. Subjects were asked to select: (1) one icon that most accurately described the driving scenario; and (2) one or more icons that would be acceptable for the driving scenario. The most accurate icon type selected by the subjects was strongly associated with the given scenario type, with the exception of collision avoidance. That is, when the driving scenario was described in general terms, subjects typically selected general icons as most accurately representing the scenario; when the driving scenario was described in specific terms, subjects typically selected specific icons as most accurately representing the scenario. In contrast to the icon accuracy, high acceptance levels were obtained for both general and specific icons regardless of the driving scenario description. Therefore, general icons are capable of meeting driver expectations and preferences for a broad range of IVIS messages. Recommendations for icon design are: (1) general icons should be used as long as they do not negatively impact driver acceptance or driver performance; and (2) for safety-related messages, specific icons will provide higher levels of driver acceptance than general icons.
    Using Driver Performance Measures to Estimate Workload BIBAFull-Text 1804-1808
      Joshua B. Hurwitz; David J. Wheatley
    This study evaluated the impact of the modality of distractor tasks and the difficulty of the driving task on driver control over a vehicle. Driving is a task with a close link between visual information processing and driver performance variables such as lane keeping. Consequently, compared to auditory distractors, visual distractors should have a larger negative effect on vehicle control, but mainly when the driving task also adds significant workload for the driver. In this study, drivers drove around either a curvy or a straight track while occasionally performing either an auditory or a visual secondary monitoring task. Performance of the secondary task was associated with deterioration in steering wheel control and lane keeping, but only on the curvy track and mainly when the secondary task required visual monitoring. These results are discussed in terms of their implication for developing workload managers in in-vehicle driver support systems.

    SURFACE TRANSPORTATION: Driver Distraction Issues: Focus on Cell Phones and Telematics [Lecture]

    Accessing Multi-Modal Information on Cell Phones While Sitting and Driving BIBAFull-Text 1809-1813
      Susan R. Fussell; Delia Grenville; Sara Kiesler; Jodi Forlizzi; Anna M. Wichansky
    Multimodal interfaces have been identified as a possible solution for reducing the visual and motor demands of small devices such as cell phones. In a within-subjects factorial experiment, we explored where audio is useful in a cell phone interface that supports database applications. Participants sat at a desk and drove in a car simulator while choosing a hotel from a descriptive long list. We compared participants' performance with and without the option to listen to the information while it was presented in text. Participants rarely preferred or used the audio option while seated. A substantial number preferred and used the audio option while driving, especially when the hotel choice task was more difficult. Those who chose the audio option looked less at the phone, but increased their task time and did not improve their driving performance. We discuss implications of reading and listening for safety and design.
    The Effects of Voice Technology on Test Track Driving Performance: Implications for Driver Distraction BIBAFull-Text 1814-1818
      Thomas A. Ranney; Joanne L. Harbluk; Y. Ian Noy
    Twenty-one subjects completed two sets of (8) laps around a 7.5-mile test track during two 4-hour sessions. They drove an instrumented vehicle while performing a combination of car following, peripheral target detection, and secondary (in-vehicle) tasks of varying complexity. Subjects performed one set of laps with each of two interfaces, voice-based and visual/manual. Secondary tasks comprised three categories including baseline tasks (radio tuning, phone dialing), simple tasks (message retrieval plus voice memo creation), and complex tasks (simple task components plus phone dialing and information retrieval from automated phone systems). Measures of driving performance, target-detection, secondary task performance and eye movements were recorded. Analyses were conducted to determine whether the voice-based interface reduced the relative distraction potential for secondary tasks of varying complexity. Generally, differences between tasks were stronger than differences between interface conditions. Measures of car-following performance, target detection, and secondary task performance revealed differences attributable to task complexity. Differences between the two interfaces were observed on peripheral target detection measures and on several driving performance measures. Overall, the benefits of using the voice-based interface were not large enough to appreciably reduce the distraction potential associated with performing the secondary tasks in the car-following scenario.
    An Experimental Evaluation of Using Automotive HUDs to Reduce Driver Distraction While Answering Cell Phones BIBAFull-Text 1819-1823
      Christopher Nowakowski; Dana Friedman; Paul Green
    To examine strategies for reducing driver distraction while answering the phone, 24 participants answered calls while driving a simulator. Calls were answered using a center-console-mounted phone or one of several phone designs which utilized a HUD to display the caller ID and steering-wheel-mounted buttons to activate the phone. Driving workload was manipulated by varying the curve radius and by varying the timing of the call, either 1 second before or 5 seconds after the start of a curve.
       The HUD-based phones resulted in response times that were 39 percent faster than the conventional center-console phone, and they resulted in up to 62 percent fewer line crossings. Additionally, when using the center-console phone, road curvature had a large influence on response times and driving performance; however, the HUD-based phone were less sensitive to increased road curvature or driving workload.
    The Attentional Costs of Interrupting Task Performance at Various Stages BIBAFull-Text 1824-1828
      Christopher A. Monk; Deborah A. Boehm-Davis; J. Gregory Trafton
    The visual occlusion technique has received considerable attention in recent years as a method for measuring the interruptible aspects of in-vehicle information system (IVIS) task performance. Because the visual occlusion technique lacks a loading task during "occluded" periods, an alternate method was adopted to provide increased sensitivity to the attentional costs of interruptions on IVIS-style task performance. Participants alternated between performing a VCR programming task and a simple tracking task. Results indicate that it does matter at which point the VCR task is interrupted in terms of time to resume the VCR task. Specifically, the resumption time, or lag, was lowest right before beginning a new task stage such as entering the show end-time, or when performing a repetitive scrolling task. The results suggest that it might be appropriate to include measures of resumption lag when testing the interruptability of IVIS-style tasks.

    SURFACE TRANSPORTATION: Heavy Vehicles, Alertness, and Emergency Events [Lecture]

    Effectiveness of Cognitive-Based and Conventional Alerters for Locomotive Engineers BIBAFull-Text 1829-1833
      Andrew R. Dattel; Stephen M. Popkin; John K. Pollard
    This is the first phase of a three-phase study that examined the effectiveness and reliability of alertness monitoring and warning devices for locomotive engineers. Four university students participated in this initial phase. Two experimental sessions were run for each participant, once during dayshift hours (9am to either lpm or 5pm) and once during nightshift hours (10pm until 2am or 6am). They completed a series of vigilance performance tasks throughout their 4-hour or 8-hour experimental session. A conventional electro-mechanical alerter commonly found on board a locomotive was used for one of the two sessions, while a novel simple cognitive-based task was used for the other session. The Psychomotor Vigilance Test (PVT) and percent eye closure (PERCLOS) were used as measures of alertness. As expected, PERCLOS and performance task reaction time (RT) increased throughout the night sessions. Furthermore, it was found that when participants were exposed to the cognitive-based alerter, they had lower PERCLOS values throughout the night sessions and shorter vigilance task RT throughout the day sessions than when they were exposed to the conventional alerter. These results are discussed with respect to adaptive automation and their potential implications.
    Effect of Distraction Complexity on Driving Performance and Emergency Event Response BIBAFull-Text 1834-1838
      Michael P. Manser; Dana M. Even
    Driver distraction is widely accepted as one factor that contributes to automobile crashes. Driver distracters include those objects or events both inside and outside the vehicle that serve to redirect the driver's attention away from the task of driving. Previous research has indicated that various degrees of distraction complexity may influence driver performance differentially. However, these results are mixed and require further examination. The present investigation examines the influence of varying levels of complexity of an in-vehicle distracter on driving performance and on the driver's reaction to an emergency event. Results indicated males exhibited greater standard deviation of lane deviation than females, and both low and high levels of distraction complexity resulted in greater lane deviation than no distraction. The theoretical and practical ramifications of the present research are discussed.
    Alertness Maintaining Tasks While Driving BIBAFull-Text 1839-1843
      Tal Oron-Gilad; Adi Ronen; Yair Cassuto; David Shinar
    The purpose of the current study was to evaluate the effectiveness of different alertness maintaining tasks on driver performance. Twelve professional truck drivers participated in five sessions of simulated driving. The first session consisted of driving without any alertness-maintaining tasks. In the following three sessions, three different alertness maintaining tasks were given during the drive. The fifth session consisted of driving while listening to music.
       The analysis of the driving performance measures shows that overall alertness-maintaining tasks may have a positive effect on driving, by slowing performance deterioration and maintaining a higher level of alertness (measured by standardized HRV). Yet, not all tasks were equally demanding. Of the three tasks evaluated, the choice reaction time task was the least demanding and failed to prevent performance deterioration. A working memory task caused a decrement in longitudinal speed, perhaps indicating that it was too demanding for most drivers to perform while driving, and was subjectively evaluated by the drivers as the most detrimental task to the driving. A trivia game task did not show any advantage in preventing performance deterioration, but was preferred by 50% of the drivers over the other two tasks.
    Light Vehicle-Heavy Vehicle Interactions: A Preliminary Assessment Using Critical Incident Analysis BIBAFull-Text 1844-1847
      Richard J. Hanowski; Robert J. Carroll; Walter W. Wierwille; Rebecca L. Olson
    Two recently completed on-road in situ data collection efforts, one involving local/short haul trucking and the other long-haul trucking, provided a large data set in which to conduct an examination of critical incidents (crashes and near-crashes) that occurred between light vehicles and heavy vehicles. Video and non-video data collected during the two studies were used to characterize critical incidents that were recorded between light vehicle and heavy vehicle drivers. Across both studies, 210 light vehicle-heavy vehicle (LV-HV) critical incidents were recorded. Of these, 78 percent were initiated by the light vehicle driver. Aggressive driving on the part of the light vehicle driver was found to be the primary contributing factor for light vehicle driver initiated incidents. For heavy vehicle driver initiated incidents, the primary contributing factor was poor driving technique. The results suggest that efforts at addressing LV-HV interaction incidents should focus on light vehicle drivers who drive aggressively. Additionally, it is recommended that heavy vehicle drivers might benefit from improved driver training that includes instruction on defensive driving.

    SURFACE TRANSPORTATION: Surface Transportation Posters

    Perceived Urgency, Alerting Effectiveness and Annoyance of Verbal Collision Avoidance System Messages BIBAFull-Text 1848-1852
      Carryl L. Baldwin; Colleen Moore
    Despite extensive examination of display parameters affecting written and nonverbal warnings, few investigators have examined presentation parameters affecting auditorially presented verbal warnings. This investigation is the first systematic examination of display parameters affecting verbal warnings that required listeners to be engaged in a contextually appropriate simultaneous task. Participants responded to verbal collision avoidance system (CAS) messages while engaged in a simultaneous simulated driving task. Perceived urgency, alerting effectiveness and annoyance ratings and behavioral reaction times were examined as a function of the signal word, CAS message, and presentation level (PL). Consistent with predictions from previous research involving written warnings, differences in the perceived urgency were observed as a function of the signal word used. PL also significantly impacted perceived urgency and alerting effectiveness. CAS messages presented at a S/N ratio of at least +4 dB resulted in high ratings of perceived urgency ratings and were responded too relatively quickly without a substantial tradeoff in increased annoyance ratings.
    Effects of Age and Memory Grouping on Simulated Car Driving BIBAFull-Text 1853-1857
      Yan Bao; Miklos Kiss; Marc Wittmann
    The effects of an onboard visual memory task on simulated car driving were investigated in 20 young and 20 elderly drivers. Three experimental tasks (memory, driving, and dual task) were conducted in this study. Grouping of the presented memory words was manipulated by color, size, shape, and location. Results showed that grouping only improves memory for young people, but not for elderly in the memory-alone condition. No memory improvement by the grouping arrangement was found in the driving situation. However, reaction time to red light and number of driving errors showed that grouping did play an important role for elderly, but not for young subjects. The concurrent memory task significantly increased elderly subjects' reaction times. Color grouping, however, led to relatively fast reaction times and fewer driving errors. Possible reasons for the age-dependent grouping effect during driving and the implications of this effect for the development of onboard instruments are discussed.
    Designing Better Traveler Information Systems: Cognitive and Task-Related Factors BIBAFull-Text 1858-1862
      Jason D'Orazio; Bruce N. Walker
    Advanced Traveler Information Systems (ATIS) attempt to enhance the navigational performance of drivers. Such assistance is greatly wanted and needed by drivers. In order to create systems that help, and not hinder, individuals, designers of ATIS should consider many aspects of human factors. One important issue of ATIS is the appropriate use and design of displays, particularly auditory displays. The use of landmarks in auditory displays may also augment navigation performance, safety, and cognitive maps. Moreover, an ATIS should be designed so that the user can perform tasks of navigation planning more naturally. Finally, the goals of an ATIS should be aligned as closely as possible to the goals of the user, in order to increase user acceptance. Consideration of the above issues will result in enhanced performance, safety, and usability of ATIS. Pilot questionnaire data has been collected that supports some of the ideas suggested in the paper.
    Occlusion Paradigm as a Tool to Assess Visual Distraction from In-Vehicle Telematics BIBAFull-Text 1863-1867
      Tracy L. Frank; Y. Ian Noy; Christopher Klachan
    Driver distraction associated with the use of on-board ITS technologies has become an issue of considerable public concern. The ease with which a task can be partitioned, referred to as task chunkability, can likely be a tool to assess the distraction potential of a secondary in-vehicle task to a driver. The present study explored the role of task chunking on distraction. Twenty-four participants, between the ages of 21 and 34, completed two separate experimental sessions. In one session they performed three in-vehicle tasks (a radio-tuning task and two simulated ITS device visual search tasks) under occlusion and while unoccluded. A task chunkability index, a ratio of the mean total shutter open time to the mean unoccluded total task time, was computed for each task. In another session, participants completed the same in-vehicle tasks while driving in a simulator at an approximate speed of 80 km/h, without occlusion. Measures of driving performance (standard deviation of lane position, the number and duration of lane exceedances, and the time to line crossing) under dual task conditions were related to corresponding chunkability indices to determine the association between task chunkability and driving performance. Results indicated that tasks differed significantly in terms of chunkability, however no differences were observed between tasks for the driving performance measures collected. A modified NASA TLX rating scale was also used to assess subjective workload for each task when performed alone and while driving. Significant differences were found between tasks in terms of mental demand, effort, frustration, and safety for both task assessment conditions. Results and implications for future research are discussed.
    The Effects of Telematics on Driver Distraction BIBAFull-Text 1868-1870
      Patrick Siebert; Mustapha Mouloua; Kendra Burns; Jennifer Marino; Lora Scagliola; Lelah Winters; Peter Hancock; Dan Agliata
    This study used both cellular phones and analogue radio to measure driver distraction and workload in a low fidelity driving simulator. Thirty-four participants performed a simulated driving task while using either a cell phone or a radio in conjunction with a secondary task assessing their spare attentional capacity. The results showed that more lane deviations were made during the cell phone and radio tuning use than both of the pre-allocation and Post-allocation phases. The secondary task errors were also higher during both the cell phone and radio tuning allocation phase than the pre-allocation and post-allocation phases. These findings indicate the greater workload load levels associated with the use of telemetric devices. These findings have major implications for driver safety and telemetric systems design.
    Voice Information System Adapted to Driver's Mental Workload BIBAFull-Text 1871-1875
      Yuji Uchiyama; Shin-ichi Kojima; Takero Hongo; Ryuta Terashima; Toshihiro Wakita
    There is a risk that voice messages from in-vehicle information systems may cause a driver to be distracted while driving. To avoid such a risk the message systems need to be adapted to drivers' mental workload. Such adaptive systems deliver voice messages when drivers' mental workload is low and postpone the messages when the driver workload is high. It is important for the system to estimate the current driver workload from car sensors such as car speed, steering wheel angle, accelerator pedal position and so on. In order to find some relations between the driver's mental workload and the data from car sensors, a dual task experiment was conducted on a public road. In the experiment, participants performed a memory task while driving an experimental car. At the same time, the data from the car sensors were recorded. The correlation coefficients between the memory task performance and the data from car sensors showed that release of the accelerator pedal was the most significant indicator of workload. Based on these results a workload estimator was developed, which has been applied to a voice information delivery test system. The potential of a voice information system that adapts to the driver's mental workload was evaluated.

    SYSTEM DEVELOPMENT: Articles

    Perspectives on Validating Complex Human-Machine System Performance BIBAFull-Text 1876-1877
      John M. O'Hara
    The performance of complex systems, such as power plants and commercial aircraft, is based on the integration of human, software, and hardware elements. They are designed to operate safely under normal and disturbance conditions. Ideally one would validate that safety and productivity goals can be achieved prior to actual operation. While some types of systems can be tested in actual operational environments, validation is especially difficult when safety or economic considerations preclude testing the types of disturbance conditions that the integrated system is designed to handle. Thus the conceptual and methodological challenges to validating such systems are significant and new approaches are emerging. The papers in this symposium will describe approaches taken to validation using examples from commercial nuclear power, civil aviation, military, and medical systems.
    Using a Benchmark-Referenced Approach for Validating a Power Plant Control Room: Results of the Baseline Study BIBAFull-Text 1878-1882
      Andrew W. Lang; Emilie M. Roth; Kent Bladh; Roger Hine
    When performing a validation study of a new system, a question arises as to what constitutes acceptable performance. One approach to setting acceptance criteria is to compare performance obtained with the new system to performance with an existing system that serves as a 'benchmark'. This paper describes an integrated system validation for a modernized power plant control room that takes the benchmark-referenced approach. In preparation for the planned integrated system validation, a baseline study of crew performance with the existing control room technology was performed using a high fidelity simulator. This paper reports the results of the baseline study and discusses their implications for validation studies of complex systems more generally. Most notably, the results establish an empirical link between process measures of performance (e.g., target detection, diagnosis, workload, teamwork, and situation awareness) and operationally significant outcome measures of performance, which reinforces the value of including process measures in validation studies.
    Human Factors Certification in Civil Aircraft BIBAFull-Text 1883-1885
      John A. Wise
    The legal version of validation is often called certification. This paper will look at some of the current human factors issues facing the civil aviation industry in a very safe system. Issues to be addressed include the real goals of certification, methods of compliance, automation, and needed changes.
    Human Performance Assessment of a Prototype Multimodal Naval Command Center BIBAFull-Text 1886-1889
      Lawrence J. Hettinger; Bart J. Brickman; James McKinney
    A user-centered design philosophy attaches primary importance to human-machine system performance as the key criterion in assessing the operational utility of complex systems. When the system under consideration is uniquely novel and emphasizes the use of relatively immature technologies, system validation must occur at a number of points in the design process. Particularly in these situations, human-system performance testing must inform engineering development throughout the entire design cycle, and not just at its conclusion. In this paper we describe an empirical effort designed to validate novel technical approaches to the design of a naval command center intended to support high levels of tactical performance in a severely reduced personnel environment. Using a human-in-the-loop simulation, we assessed the initial validity of our design concepts by measuring individual and team performance in realistic simulated tasks. By analyzing metrics associated with operational system performance, operator workload and situation awareness, we were able to identify functional aspects of the design, as well as those that needed further user-centered development.
    Methods of Assessing Medical Devices BIBAFull-Text 1890-1894
      Devorah E. Klein; Matthew J. Jordan
    While designing and validating any complex system has challenges, the medical domain has specific requirements which must be considered for a system or device to be successful. The environments, communities of use, and interactions are varied, unpredictable, uncontrolled, and ever-changing. Given the environments, communities of use, and interactions involved with medical devices, successful early and late validation of the device must be informed by the context of use itself. Building "frameworks" which represent the context of use for the device can focus validation goals, methods, and criteria and ensure that validation is directed and appropriate. In this paper we present a process and associated methods for defining the frameworks in which medical devices can be successfully assessed. The phases of the process include Phase 1: Definition in which a framework of understanding is built which represents the environment of use, community of users, and the interactions between systems and users for the medical device in development. In Phase 2: Validation the framework which defines the environment of use, community of users, and the interactions between systems and users is used to develop a validation approach and criteria. The developing device is then validated against the framework itself.
    Improving the Consideration of Human Factors in System Design BIBAFull-Text 1895-1899
      Daniel Wallace; Melissa Dugger; J. Robert Bost; Trish Hamburger; E. Johan Hendrikse; Brian Peacock
    The goal of this panel is to bring together experienced human factors professionals and systems engineers to discuss how the two groups can work together to develop optimal designs that include appropriate consideration of the human users and maintainers. The experience of the panelists covers a variety of fields, including the transportation and offshore oil industries, and government projects for the U.S. Navy and NASA. Based on their experiences, the panelists will provide recommendations for human factors professionals to improve their credibility and integration with the rest of the system design team.

    SYSTEM DEVELOPMENT: Development and Application of Human Performance Models [Lecture]

    Shipboard Communications: Quantifying Operator Capabilities And Limitations BIBAFull-Text 1900-1904
      Debra E. Bardine; Daniel F. Wallace; Udo Goff; Christine Schlichting
    As the United States Navy moves towards a reduction in manning aboard future ships, the number and complexity of tasks the warfighter must perform remains high. One responsibility of the warfighter that is very taxing on his/her audio channel is the handling of voice communications. To determine the "breaking point" in handling these voice communications, researchers used a fully developed scenario to test the capabilities and limitations of typical Navy watchstanders when subjected to a varying number of active communications circuits. Metrics such as accuracy and latency of response were used to measure human performance. In addition, a between-subject experiment was used to determine whether or not a simulated speech-to-text tool would help to improve warfighter performance on a communications task, while not degrading performance on a primary, tactical task. The experiment was performed in the Integrated Command Environment (ICE) lab at NAVSEA Dahlgren, a testbed for future command and control concepts and a vehicle to solicit valuable feedback from members of the fleet.
    Manpower, Skill and Fatigue Analysis of Future Unmanned Aerial Vehicle (Uav) Environments BIBAFull-Text 1905-1909
      Brett Walters; Michael J. Barnes
    Recent military operations conducted by the U.S. have brought to light several human factors challenges in regard to the control of unmanned aerial vehicles (UAVs). The purpose of this research was to examine the crew environment and soldier performance issues related to future UAV systems. Multiple studies were conducted using a variety of human engineering tools to address UAV crew issues related to: 1) the utility of having rated aviators as crewmembers, 2) supplementing current crews with imagery and intelligence specialists, 3) the use of automation to improve systems efficiency, and 4) the effects of crew size, rotation schedule, and fatigue on crewmember performance. No evidence was found to support a requirement for rated aviators in future Army missions. However, the use of cognitively oriented embedded training simulators was suggested to aid novices in developing the cognitive skills exhibited by experts. The effectiveness of adding imagery specialists to crews is discussed, as well as specific recommendations related to automation and crew size derived from simulation modeling.
    Human Performance Modeling and Decision Analysis in a Concept Crew Workstation BIBAFull-Text 1910-1914
      Thaddeus M. Wojcik
    As part of the effort to evaluate the performance of soldiers operating in the Vetronics Testbed Technology (VTT), a human performance model of operator processes and tasks was developed. The purpose of this effort was to gather insight into operator workload constraints, points of operator overload due to task demands, and key decision-making points and strategies employed by the operators. Operator performance was modeled when the operators were confronted with the task of controlling multiple experimental unmanned ground vehicles (XUV) in addition to performing standard Command and Control (C2) operations. The model was built using the Improved Performance Research Integration Tool (IMPRINT). Development began with a task decomposition of the current VTT system and operator control unit (OCU) and was decomposed to the button-push level of operator interaction with the unit. Next, several operational scenarios were developed to drive the simulated operator actions in the OCU and obtain measures of performance. Finally, a decision-making architecture was implemented in the model to examine points where intelligent agents and system automation could potentially aid in reducing operator cognitive demands.
    The Use of Voice and Head-Tracking for Hands-Free Human-Computer Interaction BIBAFull-Text 1915-1919
      David E. Kancler; Megan E. Gorman; Allen R. Revels
    This Practitioner Paper discusses the second in a series of studies examining the Voice Head Integrated Control (VHIC) suite, which combines use of voice commands and a head-tracking device as an alternative to the mouse and keyboard. This VHIC system is currently being investigated as a hands-free interface for accessing digitized aircraft technical manuals. The present study was conducted to validate the voice command vocabulary and provide an initial evaluation of the VHIC hardware. Aircraft maintainers from the 445th C-141 Air Force Reserve Unit served as subjects. The current study made use of the fully functioning VHIC system, complete with head-tracking and voice recognition capabilities. User strategies followed on-screen interface characteristics and the user's experience level with computers. Several error categories were tracked and subjective feedback was collected. A series of recommendations are presented which address the strategic application of the VHIC system in an aircraft maintenance environment.
    Measurement of Trust in Humans in Hybrid Inspection for Different Levels of Error Randomness BIBAFull-Text 1920-1924
      Neville Z. Ginwalla; Sittichai Kaewkuekool; Shannon R. Bowling; Anand K. Gramopadhye; Brian J. Melloy
    The focus of this research is on the effect of human trust in a hybrid inspection system with different levels of error randomness. The experimental designs were developed to conduct inspection tasks with four levels of error randomness, and subjects were requested to rate their trust at different levels in the system. Each randomness level comprised of stages, and human trust variation for each stage was observed. These levels were administered through the use of a hybrid inspection simulator. Analysis of the results revealed that human trust in the hybrid inspection system is sensitive to error randomness.

    SYSTEM DEVELOPMENT: System Development Posters

    Driver Performance Model: I. Conceptual Framework BIBAFull-Text 1925-1929
      J. M. Heimerl
    A comprehensive model that combines the necessary aspects of vehicle characteristics, manual control theory, and human sensory and cognitive capabilities (and limitations) is needed to efficiently and effectively guide experiments, and to predict or assess overall driver performance. Such a model would enable Army program managers to rank competing workload configurations and scenarios in proposed vehicles, and to focus resources on the most promising. Ultimately such a model would replace or significantly reduce reliance on the current costly process: multiple hardware iterations of "designtest-fix." Currently no such comprehensive model exists. This paper discusses a conceptual framework designed to encompass the relationships, conditions and constraints related to direct, indirect and teleoperated modes of driving, and so provides a guide or "road-map" for the construction and creation of a comprehensive driver performance model.
    Quantifying Usability: The Industry Usability Reporting Project BIBAFull-Text 1930-1934
      Jean Scholtz; Anna Wichansky; Keith Butler; Emile Morse; Sharon Laskowski
    The Industry Usability Reporting (IUSR) Project seeks to help potential corporate consumers of software obtain information about the usability of supplier products, to measure the benefit of more usable software, and to increase communication about usability needs between consumers and suppliers. Human factors and software engineers have developed a Common Industry Format (ANSI/NCITS 354-2001) for sharing usability information. Four pilot studies were conducted by industry which verify its usefulness in procurement and assess the costs and benefits of including usability test results in the software purchase process. Use of the Common Industry Format can increase communications across corporate boundaries and help improve the usability of software for consumers. The standard may also be applicable to setting usability requirements, and measuring usability of websites, hardware, and universal access.
    An Automatized Method for Human-Operator Error Analysis BIBAFull-Text 1935-1938
      Alexander M. Yemelyanov
    A method of describing and analyzing of causes for human-operator error is proposed. This method is based, on causal analysis, theory of frames and modal logic, and essentially different from commonly used statistical means. Unlike routine methods this one facilitates an analysis operator's characteristics and the situation in which the error occurred. The method makes it possible for every error to reveal its intrinsic sources, which can be used for making recommendations concerning their elimination. On the basis of the suggested method, a computer-aided system SAFE was developed which was implemented in aviation to analyze errors of pilots / crew members and air traffic controllers. The proposed methodology and the associated software may be implemented for the analysis of operator errors in any control system.

    TEST AND EVALUATION: Test and Evaluation: Research, Tools, and Techniques [Lecture]

    Effective Ivis Icon Comprehension Research: Context and Response Scaling Methods BIBAFull-Text 1939-1943
      Joel B. Richman; John L. Campbell; Marvin C. McCallum
    A refined approach used to determine the comprehension level of in-vehicle information system (IVIS) icons is introduced. This approach provides three primary improvements over classical evaluation procedures (e.g., ISO, 2001). First, this approach recommends the inclusion of context to ensure realistic comprehension scores. Second, the scaling method employed provides concrete, well-defined measurement criteria based on major and minor elements included in the icon message. Third, this approach allows the comprehension testing team to provide better diagnostic information back to the icon designers because it allows for analysis of what element(s) of the icon the subjects seemed to understand and what element(s) may have led to errors in comprehension. We recommend using this approach to provide high quality comprehension information for IVIS icon evaluations.
    Quantification of Adverb Intensifiers for use in Ratings of Acceptability, Adequacy, and Relative Goodness BIBAFull-Text 1944-1948
      Stephen J. Krsacok; William F. Moroney
    Survey designers often assume the existence of an underlying linear continuum with equal intervals between anchors when they create a scale. However, this is not necessarily the case when labels, such as "somewhat acceptable," "completely acceptable", etc. are assigned to these intervals. This study examines numeric ratings assigned by college students to adverb intensifiers.
       Numeric ratings (from -5 to + 5) were collected from college males (n=54), college females (n=54) for positive and negative adverb-intensifiers of acceptability (n=50), adequacy (n=50), and relative goodness (n=41). Minimal differences were noted in mean ratings, variability, and order of the ratings assigned by males and females.
       Three different scale development strategies were utilized to develop 54 adverb intensifier scales with intervals of 5, 6, 7, 8, 9, and 11 descriptors for acceptability, adequacy, and relative goodness. Survey designers are invited to use these scales or the raw data to develop their own scales. Those who do so will have the advantage of using data based on a current college population.
    Performance Testing and Subjective Evaluation: Giving Equal Importance to Both BIBAFull-Text 1949-1953
      Laurie L. Quill; David E. Kancler; Allen R. Revels; Carlton D. Donahoo; Megan E. Gorman; Matthew W. Goddard
    The key to finding real issues with, and benefits of a product or system is to collect and merge findings from both empirical performance testing and subjective evaluation methods. As practitioners, Human Factors professionals are frequently challenged with identifying cost effective solutions that also meet enduser needs for usability. If the system is not usable from the end-user's perspective, performance enhancements cannot be achieved. Likewise, if the system is very usable but does not provide any process improvement, then it is not likely to be purchased. Reconciling and communicating differences in findings between empirical and subjective data is challenging. This paper provides a systematic method for providing value for all product or system users, including individuals with such disparate needs as management and end-users. The paper incorporates recognized usability testing methods for addressing detailed usability concerns, includes a method of systematic testing called the LSF Process, and introduces a means of communicating subjective feedback through cluster graphs.
    A New Test of Self-Paced Work Sensitive to the Effects of Prolonged Work and Sleep Deprivation BIBAFull-Text 1954-1958
      William J. Tharion; Scott J. Montain; Cara D. Leone; John W.