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Proceedings of the Human Factors and Ergonomics Society 49th Annual Meeting 2005-09-26

Fullname:Proceedings of the Human Factors and Ergonomics Society 49th Annual Meeting
Location:Orlando, Florida
Dates:2005-Sep-26 to 2005-Sep-30
Standard No:ISBN: 0-945289-26-X; hcibib: HFES05; TA 166 H794
Links:Online Proceedings | Conference Home Page (defunct) | Online Order Form
  1. HFES 2005-09-26 Volume 49
    1. AEROSPACE SYSTEMS: Practical Looks at Extreme Aviation: Spaceflight and Unoccupied Aerial Vehicles
    2. AEROSPACE SYSTEMS: Avoiding Conflicts from the Ground and Air
    3. AEROSPACE SYSTEMS: NeoWickenson Aviation
    4. AEROSPACE SYSTEMS: Displays
    5. AEROSPACE SYSTEMS: Practical Looks at Perception and Cognition in Aviation
    6. AEROSPACE SYSTEMS: Challenges to Aviation Safety: Language, Weather, and Fatigue
    8. AGING: Older Adults and Computer Technology
    9. AGING: Exploring Age Differences in Kinematics, Perception, and Cognition
    10. AGING: Posters
    11. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Task Analysis for Design and Explanation
    12. COGNITIVE ENGINEERING AND DECISION MAKING: Contemporary Issues in Cognitive Engineering
    13. COGNITIVE ENGINEERING AND DECISION MAKING: Military Team Communications, SA, and Cognitive Modeling
    14. COGNITIVE ENGINEERING AND DECISION MAKING: Decision Aiding in Military and Intelligence Systems
    15. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Systems Engineering and Work Analysis
    16. COGNITIVE ENGINEERING AND DECISION MAKING: Information Processing, and Information and Feedback Displays
    17. COGNITIVE ENGINEERING AND DECISION MAKING: Good Design Ideas Gone Bad: Lessons Learned When System Designs Do Not Work as Planned
    18. COGNITIVE ENGINEERING AND DECISION MAKING: Transportation Systems and Human Performance
    19. COGNITIVE ENGINEERING AND DECISION MAKING: Advances in Human-Robot Interaction
    20. COGNITIVE ENGINEERING AND DECISION MAKING: Ecological Interface Design, and Decision Biases and Styles
    21. COGNITIVE ENGINEERING AND DECISION MAKING: Human-Robot Interaction: From Fieldwork to Simulation to Design
    22. COGNITIVE ENGINEERING AND DECISION MAKING: Interruptions, Distractions, and Attention Management: A Multifaceted Problem for Human Factors
    23. COGNITIVE ENGINEERING AND DECISION MAKING: Trust in Automation and Information Presentation
    24. COGNITIVE ENGINEERING AND DECISION MAKING: Emergency, Crisis Management, and Knowledge Elicitation
    27. COMMUNICATIONS: Speech Communications with Humans and Computers
    28. COMMUNICATIONS: Posters
    29. COMPUTER SYSTEMS: Keyboards and Text Entry
    30. COMPUTER SYSTEMS: Input Methods and Display Design
    31. COMPUTER SYSTEMS: Innovative Usability Methods
    32. COMPUTER SYSTEMS: Posters
    33. DEMONSTRATIONS: Demonstrations of Novel Interfaces
    34. DEMONSTRATIONS: Demonstrating Design for the Virtual and Real World
    35. EDUCATION: Teaching Team Behavior to Human Factors/Ergonomics Students, Part II: Specifics for Forming and Developing Teams, and Using Peer Ratings
    36. EDUCATION: Education Potpourri
    37. EDUCATION: Posters
    38. ENVIRONMENTAL DESIGN: Environmental Design Features: Inside & Outside the Workspace
    39. ENVIRONMENTAL DESIGN: Environmental Workspace Issues and Organizational Culture: In Offices, Retail, and Manufacturing Settings
    41. FORENSICS PROFESSIONAL: Practice and Research in Forensic Human Factors
    43. GENERAL SESSION: General Sessions Potpourri
    44. GENERAL SESSION: Levels of Automation in the Brave New World: Adaptive Automation, Virtual Presence, and Swarms, Oh My!
    45. GENERAL SESSION: Homeland Security
    46. GENERAL SESSION: Beyond Requirements: Improving Software Tools for Intelligence Analysts
    47. GENERAL SESSION: Posters
    48. HEALTH CARE: Reducing Health Care Errors
    49. HEALTH CARE: Design Issues in Health Care Systems
    50. HEALTH CARE: Decision Making and Mental Workload in Health Care Systems
    51. HEALTH CARE: Usability Issues in Medical Systems
    52. HEALTH CARE: Medical Systems and Training
    53. HEALTH CARE: Medical Devices and Safety
    54. HEALTH CARE: Posters
    55. HUMAN PERFORMANCE: Kickoff Address: Human Performance Modeling -- A Historical Perspective
    56. HUMAN PERFORMANCE: Human Performance Models of Pilot Behavior
    57. HUMAN PERFORMANCE: From Models to Methods to Models: Tools and Techniques for Using, Developing, and Analyzing Cognitive Human Performance Models
    58. HUMAN PERFORMANCE: Current R&D in Human Performance Modeling
    59. HUMAN PERFORMANCE: Novel Applications of Simulation Technology in the U.S. Army
    60. HUMAN PERFORMANCE: Lessons Learned and the Future of Human Performance Modeling
    61. HUMAN PERFORMANCE: Posters
    62. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Are We Ready to Consider Individual Differences in Human Capabilities in Our Workplace Design?
    63. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Human Performance
    65. INDUSTRIAL ERGONOMICS: Injury Pathways
    66. INDUSTRIAL ERGONOMICS: Slips, Trips, and Falls
    67. INDUSTRIAL ERGONOMICS: Low Back Biomechanics
    68. INDUSTRIAL ERGONOMICS: The History and Future of Ergonomics in Controlling Low Back Disorders
    69. INDUSTRIAL ERGONOMICS: Intervention Effectiveness
    70. INDUSTRIAL ERGONOMICS: Assessment Tools
    71. INDUSTRIAL ERGONOMICS: Ergonomics Potpourri
    73. INTERNET: Internet
    74. INTERNET: Posters
    75. MACROERGONOMICS: Macroergonomics in Health Care
    76. MACROERGONOMICS: Participatory Ergonomics and Multicultural Factors in Decision and Computer Work Systems
    77. MACROERGONOMICS: Trends in Macroergonomics
    78. MACROERGONOMICS: Posters
    79. PERCEPTION AND PERFORMANCE: Attention/Vigilance/Alarms
    81. PERCEPTION AND PERFORMANCE: Overarching Principles of Display Design
    82. PERCEPTION AND PERFORMANCE: Spatial Displays
    83. PERCEPTION AND PERFORMANCE: Audio Displays & Sonification
    84. PERCEPTION AND PERFORMANCE: Issues in Object Identification and Motion in Complex Displays
    86. PRODUCT DESIGN: Product Design Aesthetics and Methods
    87. PRODUCT DESIGN: The Role of Hedonomics in the Future of Industry, Service, and Product Design
    88. PRODUCT DESIGN: Product Design
    89. PRODUCT DESIGN: Design Potpourri
    90. PRODUCT DESIGN: Posters
    91. SAFETY: Arnold Small Lecture in Safety
    92. SAFETY: Safety Potpourri
    93. SAFETY: Warnings and Decision Making
    94. SAFETY: Posters
    95. STUDENT FORUM: Training and Cognitive Engineering
    96. STUDENT FORUM: Achieving Success in the Hf/E Field: Expert Advice on How to Become a Future Expert!
    97. STUDENT FORUM: Human-Computer Interaction
    98. STUDENT FORUM: Virtual Environments
    99. SURFACE TRANSPORTATION: Intersections, Teens, and Teens in Intersections
    100. SURFACE TRANSPORTATION: Internal and External Factors: Driver Impairment and Nighttime Driving
    101. SURFACE TRANSPORTATION: About Driver Awareness Systems: "I'm a Good Driver; It's Everyone Else"
    102. SURFACE TRANSPORTATION: Practice and Method: A Conglomeration
    104. SYSTEM DEVELOPMENT: Expanding Dod Human Systems Integration Demands -- Can We Deliver What is Needed?
    105. SYSTEM DEVELOPMENT: Human Factors for NASA's Space Exploration Vision -- The View from Inside
    106. SYSTEM DEVELOPMENT: Modeling the User in Large Systems
    107. SYSTEM DEVELOPMENT: Integration through Education: Teaching Human Factors in the Workforce
    109. TEST AND EVALUATION: Issues in Usability Testing
    110. TEST AND EVALUATION: Empirical Issues in Test and Evaluation
    111. TEST AND EVALUATION: Poster
    112. TRAINING: Methods for Assessing and Debriefing Team and Multiteam Performance in Distributed Simulation-Based Training
    113. TRAINING: Training Process and Performance in Teams and Human-Agent Teams
    114. TRAINING: Cognition and Training: Advancing Training Technology to Support Cognitive Processes
    115. TRAINING: Conceptual and Technological Innovations in Training
    116. TRAINING: Posters
    117. VIRTUAL ENVIRONMENTS: Human Interactions in Virtual Environments
    118. VIRTUAL ENVIRONMENTS: Assessing and Enhancing Team Training Technologies: From the Lab to the Field

HFES 2005-09-26 Volume 49

AEROSPACE SYSTEMS: Practical Looks at Extreme Aviation: Spaceflight and Unoccupied Aerial Vehicles

Human Factors Assessment of International Space Station (ISS) Medical Equipment Packs BIBAFull-Text 1-4
  Danielle Paige Smith; Vicky E. Byrne; Mihriban Whitmore
A human factors assessment was performed on several International Space Station (ISS) medical packs to evaluate the organization of items and provide recommendations for redesign. The overall goal was to recommend solutions that will improve the efficiency of identifying and locating items in the medical packs, thereby, potentially increasing the survival rate of crewmembers in the event of a medical emergency. Currently, each ISS crew remains on-orbit for six-month intervals. As there is not a standing requirement for a physician crewmember, the maintenance of crew health is dependant on individual crewmembers delivering care via telemedicine and their own limited training. In addition, medical procedures must be carried out within the limitations imposed by the unique physical environment of the space station. Given these challenges, the procedures and equipment designed to aid the crewmember in delivering that care should follow human-centered design principles in order to be as easy and simple to use as possible. The evaluation revealed six main categories of issues: Labeling, Location/Collocation of items, Clear Presentation of Information, Error Prevention, Stowage, and Equipment Design. Recommendations for each category are provided, and should be considered for efficiency and effectiveness in any medical environment.
Habitability in Space BIBAFull-Text 5-9
  Cynthia M. Rando; Susan D. Baggerman; Laura E. Duvall; Lockheed Martin
Over the last 40 years NASA has made great strides in creating habitable environments that support long-term space exploration. Most recently, the Skylab, Mir, and International Space Station exploration endeavors have provided NASA with a wealth of lessons learned to be carried forth to the new national vision for space exploration: "to the moon, Mars and beyond." This paper will focus on the challenges and successes associated with creating a safe, functional, and productive environment for the human being living in space for an extended length of time. Specifically, the authors will be focusing on the issues surrounding habitation in space including: crew sleeping quarters, food preparation and dining facilities, exercise countermeasures, personal hygiene and waste collection, crew leisure time, and internal vehicle configuration. The lessons learned will be used to make recommendations for future long term space exploration.
Evaluation of the Space Shuttle Cockpit Avionics Upgrade (CAU) Displays BIBAFull-Text 10-14
  Jeffrey W. McCandless; Robert S. McCann; Kelsey W. Berumen; Stephen S. Gauvain; Victoria J. Palmer; William D. Stahl; Andrew S. Hamilton
In 1999, NASA Johnson Space Center (JSC) initiated a Cockpit Avionics Upgrade (CAU) project to increase shuttle mission safety by improving the crew's situation awareness, reducing their workload, and improving their performance. The primary focus of the project was a complete redesign of the current cockpit displays. To determine the effectiveness of the redesigns, a human-centered evaluation was conducted in the Shuttle Mission Simulator (SMS) at NASA JSC in 2003 and 2004. Measures of crew situation awareness, workload, and nominal and off-nominal task handling performance were made in a series of simulations of off-nominal flight situations during the dynamic flight phases of ascent and entry. The redesigned display formats yielded dramatic increases in situation awareness, reductions in workload, and improvements in performance.
The Playbook Approach to Adaptive Automation BIBAFull-Text 15-19
  Christopher Miller; Harry Funk; Peggy Wu; John Meisner; Marc Chapman
SIFT has pioneered a human-automation integration architecture, called Playbook, based on a shared model of the tasks in the domain. This shared task model provides a means of human-automation communication about plans, goals, methods and resource usage -- a process akin to referencing plays in a sports team's playbook. The Playbook enables human operators to interact with subordinate systems with the same flexibility as with well-trained human subordinates, thus allowing for adaptive automation. We describe this approach and its application in an ongoing project called Playbook-enhanced Variable Autonomy Control System (P-VACS).
The Human Challenges of Command and Control with Multiple Unmanned Aerial Vehicles BIBAFull-Text 20-24
  Bruce P. Hunn
The unmanned aerial vehicle represents a significant challenge to its operators since they are literally out of touch with the system they control. Operating from remote sites miles from the vehicle they control, they are isolated by space and time from a direct connection to the machine they operate. While the pilot of a manned aircraft can always receive some type of direct feedback from the machine they operate, even if they lose all their control and display systems, they can still perceive many qualities of that machine's system state merely from their senses. However, in contrast, the unmanned system is based solely on an electronic link connecting the operator to their vehicle. This paper will review the historical trends in remote vehicle operation and discuss state-of-the-art in remote control systems as they apply to single or multiple unmanned aerial vehicles.

AEROSPACE SYSTEMS: Avoiding Conflicts from the Ground and Air

Deconstructing Complexity in Air Traffic Control BIBAFull-Text 25-29
  M. L. Cummings; Chris Tsonis
While previous research has addressed air traffic controller workload as a function of cognitive complexity due to environmental and to a lesser degree, organizational factors, significantly less attention has been paid to the role of displays and complexity in the ATC environment. One drawback to new display technology is that in dynamic human supervisory control domains, it is not always clear whether a decision support interface actually alleviates or contributes to the problem of complexity. In an attempt to quantify the influence of environmental and display complexity factors on cognitive complexity, an experiment was conducted to determine if these two components could be effectively measured. Results revealed that the environmental factor of increasing aircraft number affected subject performance only slightly more than the display complexity factor of increased color categories. These findings are important because the use of color in displays is meant to reduce environmental complexity, not add to it.
Evaluating Controller Use of Advanced Weather Products by Evaluating User Interaction Patterns BIBAFull-Text 30-34
  Ferne Friedman-Berg; Ulf Ahlstrom
We evaluated how Terminal Radar Approach Control (TRACON) controllers interacted with advanced weather products when displayed on primary tactical radar displays or on auxiliary flat-panel displays. When we provide the controllers with access to appropriate weather tools, we potentially decrease workload and improve performance by increasing weather situational awareness (WSA). We assessed the benefit of providing weather information using Gantt charts to graphically depict user interaction patterns and by conducting an analysis of the frequency and duration of interactions with the weather tools. From these analyses, we identified two patterns of interacting with tools corresponding to heavy and light users. We correlated tool use with our measure of controller efficiency and found an increase in traffic throughput with increasing tool use. We also determined that the controllers were more likely to interact tactically with tools when placed on the Terminal Controller Workstation (TCW), turning them on when needed and turning them off when not needed. This method provides us with insight into how the controllers use the information on their displays to help provide them with tools to increase safety and efficiency.
Evaluating Visualization Modes for Closely Spaced Parallel Approaches BIBAFull-Text 35-39
  Ronald Azuma; Jason Fox; Chris Furmanski
Raytheon's TACEC (Terminal Area Capacity Enhancement Concept) proposes to increase airspace capacity by using closely-spaced formations of arriving and departing aircraft to greatly increase airport capacities. However, a blunder in a tightly-spaced formation could cause a collision with another aircraft or its wake vortices. Therefore, humans need tools and visualization aids to detect and respond to blunders. This paper is the first in a series of experiments to evaluate the ability of different visualization modes to enable detection of lateral blunders. We tested four viewpoints, one warning aid, and three blunder speeds in a within-subjects design. This study had twelve participants. The main result was that changing the viewpoint made a large difference; the cockpit view was by far the worst. Blunder detection varied by speed and was difficult in the presence of noise. Future experiments should use more realistic simulators and pilots as participants.
Display Dimensionality and Conflict Geometry Effects on Maneuver Preferences for Resolving In-Flight Conflicts BIBAFull-Text 40-44
  Lisa C. Thomas; Christopher D. Wickens
With the presence of a cockpit display of traffic information (CDTI) that provides graphical airspace information, pilots can use a variety of conflict resolution maneuvers in response to how they perceive the conflict. Inconsistent preference findings from previous research on conflict resolution using CDTIs may be due to inherent ambiguities in 3-D displays and/or a limited range of conflict geometries. This paper describes a study that investigates conflict resolution maneuver preferences using three displays with different frames of reference and a wide range of conflict geometries. Results indicate that 3-D displays with interactive viewpoints reduced spatial ambiguities. The interactive 3-D displays produced a preference for vertical maneuvers over lateral similar to a 2-D coplanar display; however this preference was reversed under increased workload conditions for both 3-D displays. Pilots in all three display conditions showed a preference to maneuver vertically away from intruders, though this was eliminated (or reversed) as workload increased. The 2-D coplanar display induced a preference to laterally turn away from approaching intruders, which overwhelmed a trained "turn right" preference.

AEROSPACE SYSTEMS: NeoWickenson Aviation

Mixed Fleet Flying Between Two Commercial Aircraft Types: An Empirical Evaluation of the Role of Negative Transfer BIBAFull-Text 45-48
  Beth Lyall; Christopher D. Wickens
We examined the potential vulnerabilities of pilots flying a mixed fleet of two different aircraft types. A "worst case" scenario was evaluated in which a pilot, flying one type exclusively, would need to fly the different type, after 6 months without any recurrency training on the latter. These circumstances invite negative transfer of habits in the "old" aircraft, to performance in the "new" aircraft". Documents of both aircraft were evaluated to establish those aspects of design and procedures differences that invite such negative transfer; a list of 36 such "vulnerabilities" were identified. Then 40 active commercial airline pilots from a US carrier participated in an evaluation of such negative transfer between two different types within the fleet. The sample was divided into 2 groups each of which normally flew one of the types and not the other. After training on the "new" type, each pilot returned to either 3 or 6 months of flying exclusively with their "old" type, and then returned for simulator evaluations on the "new" type that were targeted to reveal the 36 vulnerabilities. Even with power-sensitive statistical analyses, only slight evidence for negative transfer was found. Those areas where such transfer did emerge were targeted for recommendations of either procedural harmonization or minor design changes.
Adaptive Information Fusion for Situation Awareness in the Cockpit BIBAFull-Text 49-53
  Samuel M. Waldron; Geoffrey B. Duggan; John Patrick; Simon Banbury; Andrew Howes
Evidence is provided pointing to potential caveats associated with the use of information fusion techniques in the cockpit. Six pilots each with a minimum of ten years flight experience completed a series of missions using a simulated future jet cockpit. Each trial required a pilot to guide their aircraft towards a fixed location. The pilot was required to estimate the position of this location both during and five minutes after the flight. Different types of fusion were manipulated with regard to the information presented on a touchscreen display -- Fused, Fused Drill-Down, and UnFused. Data suggested that information fusion alone can have negative consequences for both task performance and subsequent recollection of information. It is argued that reductions in system transparency and transfer-appropriate processing may account for these findings.
Effects of the Space Shuttle Cockpit Avionics Upgrade on Crewmember Performance and Situation Awareness BIBAFull-Text 54-58
  Miwa Hayashi; Valerie Huemer; Fritz Renema; Steve Elkins; Jeffrey W. McCandless; Robert S. McCann
The Space Shuttle Cockpit Avionics Upgrade (CAU) is a proposed cockpit display upgrade designed to address human-factors usability issues of the current suite of cockpit displays, Multifunction Electronic Display System (MEDS). Unlike MEDS, CAU consolidates information in a task-oriented manner, rather than a data-source-oriented manner. CAU also makes greater use of color coding and graphical depictions in systems status presentations. An ascent-phase operation simulation study showed that CAU formats significantly improved the participants' abort-related situation awareness. Participants also performed certain malfunction management procedures more accurately when CAU was used. The Space Shuttles are now scheduled to be retired by 2010 without incorporating CAU; however, the results of the present study suggest that the human-centered design concepts are effective and can be extended to the cockpit interface design of NASA's next generation Crew Exploration Vehicle.
Use of a Functional Aviation Display Under Varying Workload Conditions BIBAFull-Text 59-63
  Carl F. Smith; Steve Fadden; Deborah A. Boehm-Davis
Twenty pilots performed flight maneuvers on a flight simulator over three levels of workload with either a conventional or alternative display that incorporates functional information. Pilots' performance with the functional display (OZ) showed greater control of power and position, as well as improved performance on a secondary task. The role of increased workload with functional displays and the potential of functional information in future aviation displays are discussed.
Evaluating control activity as a measure of workload in flight test BIBAFull-Text 64-67
  S. Jennings; G. Craig; Stephan Carignan; Kris Ellis; D. Thorndycraft
This paper describes an investigation of a workload measurement technique based on pilot control movements. The Dynamic Interface Modeling and Simulation System Product Metric (DIMSS PM) assumes that pilot control activity can be used to evaluate pilot workload. Three qualified test pilots flew the fly-by-wire NRC Bell 205 helicopter in a short test program that compared the DIMSS PM with subjective workload ratings and handling qualities ratings. The pilots performed a variation of an ADS-33E bob-up with varying levels of simulated turbulence and modified cyclic control characteristics. Good agreement was found for most in-flight test conditions between DIMSS Workload Metric scores and subjective workload ratings from the Bedford Workload Scale and Cooper-Harper handling qualities ratings. While, the DIMSS Workload Metric did not accurately reflect workload increases due to variations in the cyclic stick characteristics, the metric shows promise as an objective measurement tool of pilot workload in well-defined tests.


Flightpath Tracking, Change Detection and Visual Scanning in an Integrated Hazard Display BIBAFull-Text 68-72
  Amy L. Alexander; Christopher D. Wickens
Twenty-four certified flight instructors were required to fly a series of curved, step-down approaches while detecting changes to surrounding traffic aircraft and weather cell icons on two integrated hazard display (IHD) formats (2D coplanar and split-screen) under varying workload levels. Generally, it appears that the 2D coplanar IHD was better in supporting flightpath tracking and change detection performance when compared to a split-screen display. Pilots exhibited superior flightpath tracking (in the vertical dimension, and under low workload) when using the 2D coplanar IHD, although this effect was mitigated by increasing workload such that tracking deteriorated faster with the 2D coplanar than the split-screen display. The spawned 3D cost of diminished size with distance from ownship played a role in change detection response time -- pilots were slower (particularly in detecting traffic aircraft changes) with the split-screen compared to the 2D coplanar IHD. These effects will be discussed within the context of visual scanning measures.
The Contaminating Influence of Display Size on Flight Control, Risk Assessment, and Route Selection BIBAFull-Text 73-77
  Emily K. Muthard
The present experiment was designed to examine the effect of display size on distance estimates used for flight control and in assessing risk for route selection. Sixteen pilots were asked to select and fly along a route using integrated hazard and primary flight displays. Display size was manipulated by altering the physical size of a two-dimensional display and through axis compression in a three-dimensional display. Display minification resulted in poorer flight control. When the display was enlarged, pilots were found to overestimate the distance from the flight path to impending hazards and subsequently choose riskier routes. Pilots also exhibited greater confidence in their route choices with the large display, even though their choices were more dangerous. Results suggest that display size must be considered when designing displays for spatial tasks.
Using Terrain-Depicting Primary Flight Displays for Performing Instrument-Referenced Tasks: Can We Empirically Test for Equivalent Level of Safety BIBAFull-Text 78-82
  Dennis B. Beringer; Jerry D. Ball
A study was conducted to determine if primary flight displays (PFDs) depicting terrain could be used with a level of safety equivalent to electronic attitude-direction indicators (EADIs) without terrain. Five groups of 8 pilots each flew scenarios in a flight simulator using one of three PFDs with or without guidance cues. Performances of instrument-referenced maneuvers using the EADI were measured, followed by trials with an experimental format. Performance measures included initial response time, total recovery time, and control reversals. Traditional parametric analyses found no significant performance differences between groups. Analyses using confidence intervals to assess equivalence of distributions showed group performances were essentially the same. Pilot preferences were examined and are reported. It was concluded that the specific terrain representations did not reduce the level of safety for these specific maneuvers. This technique is recommended for applicants wishing to demonstrate a level of safety equivalent to existing systems.
Characterizing Scan Patterns in a Spacecraft Cockpit Simulator: Expert Versus Novice Performance BIBAFull-Text 83-87
  Valerie A. Huemer; Miwa Hayashi; Fritz Renema; Steve Elkins; Jeffrey W. McCandless; Robert S. McCann
Operating a spacecraft is a complex and demanding task that requires years of training and constant monitoring of both navigation and systems parameters. By examining differences in scanning between "expert" and "novice" operators, we can develop cognitive models of scanning behavior or enhance training. In the Intelligent Spacecraft Interface Systems (ISIS) laboratory, we measure eye movements and record performance parameters in a part-task space shuttle cockpit simulator. We trained airline transport pilots (as our "novice" group) on fundamentals of flying an ascent ("launch-to-orbit") in the space shuttle. We tested three levels of malfunctions occurring during a trial -- none (nominal), one malfunction, or three malfunctions -- on both pilots and astronauts (our "expert" group). Astronauts had fewer errors and faster reaction times. Eye movement analyses showed that both astronauts and pilots similarly modified their scan strategies depending on the flight segment and how many malfunctions occurred during a trial.
Sensor Control Effectiveness and Display Design in an Imaging System for Airborne Search and Rescue BIBAFull-Text 88-92
  Jocelyn Keillor; Tyler Hause; Nada Pavlovic; Michael Perlin
Traditionally, search and rescue (SAR) technicians have conducted search by directly viewing the terrain below the aircraft. Defence R&D Canada is developing a multi-sensor imaging system for SAR that would replace direct inspection under low visibility conditions. The operators may orient the sensors in any direction, which combined with a narrow field-of-view may induce disorientation. In addition to detecting and discriminating objects within the sensor's field-of-view, an operator is responsible for moving the sensor in such a way as to ensure that this detection and discrimination may be carried out with similar effectiveness across the entire area that needs to be searched. The present study reports the development of a metric of coverage effectiveness, and its application to two simulation experiments. The results demonstrate a trade-off between the availability of a moving-map display necessary to preserve operator orientation, and the effectiveness of an operator's sensor coverage over a specific region. That is, sensor control effectiveness was compromised by the addition of a moving-map to the display, likely due to operators' inability to simultaneously inspect the map and move the sensor appropriately. The coverage effectiveness metric reported here would be a useful tool in the development and evaluation of "smart" automation of this sensor sweep function.

AEROSPACE SYSTEMS: Practical Looks at Perception and Cognition in Aviation

Color Usability on Air Traffic Control Displays BIBAFull-Text 93-97
  Ulf Ahlstrom; Larry Arend
Modernization of Air Traffic Control (ATC) display systems includes increased use of color to code information. While colors can enhance display designs, human factors issues like legibility and salience manipulation are still problematic. Here, we address some of the potential usability issues with integrating traffic and advanced weather information on controller displays. We argue that color palettes that are not specifically designed for layered data and a large number of objects can create legibility and salience problems. We discuss the use of luminance contrast to manipulate salience and present some empirical data showing that air traffic controllers display large individual differences in their preferred brightness settings. We argue that user adjustments of luminance contrast for salience manipulation must be severely constrained in future ATC displays. We present a prototype color palette that uses color-coding to prioritize display information while maintaining good legibility.
Validation of an Objective Behaviorally-Based Usability Method for Real-Time Assessments BIBAFull-Text 98-102
  Kimberly R. Raddatz; Peter D. Elgin; John Uhlarik
Rapid increases in computer and data-link technology have resulted in revolutionary but complex displays that comprise integrated cockpits. Consequently, usability techniques must evolve to ensure that advances in information quantity do not compromise information quality, thereby compromising safety. The UserCHAT is a usability method designed to maximize efficient diagnosis of usability problems identified from a behaviorally-based perspective while minimizing time and resource limitations associated with typical assessments. The present study sought to validate the UserCHAT as a suitable methodology that provides accurate real-time identification of usability problems by evaluators with little usability training. Expert and Intermediate evaluators accurately recorded over 80% of first inefficient actions performed by users on benchmark tasks using a relatively complex MFD while Novices with minimal training with UserCHAT captured over 65%. These results suggest that the UserCHAT does not require extensive evaluator training to effectively record user performance and thereby identify usability problems.
Enhancing Airport Surface Markings to Support Pilot Awareness About Runway Location BIBAFull-Text 103-107
  Peter M. Moertl; Steven L. Estes; Cheryl R. Andrews; Oscar B. Olmos
Enhancements to airport surface markings were developed to facilitate pilot awareness of the runway location and to increase the conspicuity of the holding position markings, see Olmos, Andrews, and Estes (2003). The marking enhancements were evaluated in a simulation and two field studies. In a simulation study, general aviation (GA) pilots as well as transport category pilots performed taxi operations using a cockpit simulator. The simulated airport surface included enhanced surface markings and the distance at which pilots detected the runway environment was measured under various conditions. The results indicate that marking enhancements were associated with an earlier detection of the runway in some but not in all conditions. Specifically, transport category pilots detected simple taxiway-runway intersections with enhanced markings earlier than with current markings. No such perceptual advantage was found for GA pilots or at complex intersections. Most pilots, however, subjectively preferred the marking enhancements over the current marking standard. These positive evaluations of enhanced markings were confirmed by two field demonstrations where two sets of enhanced markings were implemented at two US airports. Pilots perceived the benefits of the marking enhancements to depend on pilot experience, familiarity with the airport, aircraft type, and knowledge about the marking enhancements. For certain airport situations, the enhanced markings in the hold-short environment of runways can be expected to aid pilot awareness about the runway location.
Arriving from Delphi at O'Hare: Predictive Cognitive Engineering in the O'Hare Modernization Project and Beyond BIBAFull-Text 108-112
  Steven Estes
This paper describes a cognitive modeling effort for the O'Hare Modernization Project (OMP). Beginning with a statement of the problem, it describes how cognitive modeling was used to measure the mental workload and work time of controllers running various positions at O'Hare International Airport, both under the current airport configurations and a future set of configurations (proposed in the OMP). The O'Hare case is used as an exemplar of the type of data that can be acquired with relatively simple cognitive models.
Interface Heuristics and Style Guide Design: An Air Battle Management Case Study BIBAFull-Text 113-117
  W. Todd Nelson; Robert S. Bolia
This paper describes the development of a human-machine interface style guide designed to promote a common look and feel among operator interfaces employed by air battle managers in the United States Air Force, and to reduce training requirements for operators moving between platforms. An analysis of the content of extensive operator interviews from all relevant platforms preceded the production of a compact style guide based on a few simple heuristics and populated with wire frame illustrations devised to act as examples of interfaces that were either compatible or incompatible with each rule. This novel methodology will be discussed as applied to the air battle management work domain, and in the context of its ability to produce usable style guides.

AEROSPACE SYSTEMS: Challenges to Aviation Safety: Language, Weather, and Fatigue

Investigating Pilot Performance Using Mixed-Modality Simulated Data Link BIBAFull-Text 118-122
  Jeff A. Lancaster; John G. Casali
Research exploring new technology integration into general aviation (GA) cockpits is lacking, especially that which focuses on the capabilities and limitations of the single pilot. Sixteen visual flight rules (VFR) rated pilots were evaluated for data link communication performance using a flight simulator equipped with a mixed-modality simulated data link within one of two flight conditions. Modalities included textual, synthesized speech, digitized speech, and synthesized speech/textual combination. Flight conditions included VFR (unlimited ceiling, visibility) or marginal VFR (MVFR) flight conditions (clouds 2800 feet, three-mile visibility). Evaluation focused on the time required accessing, understanding, and executing data link commands. Measures to evaluate workload, situation awareness, and subjective preference were also obtained. Results indicated performance, mental workload, and situation awareness differences across data link modalities and between flight conditions. Implications for operational safety in future systems that incorporate data link for use by a single pilot are discussed.
Language Error in Aviation Maintenance: Data from Asia BIBAFull-Text 123-127
  C. G. Drury; J. Ma
English is the language of aviation, including aviation maintenance. As more maintenance work is outsourced to non-English-speaking countries, language error may be a problem. A study of 254 maintenance personnel at nine sites in Chinese-speaking countries measured the reported incidences of seven scenarios and tested intervention effectiveness. Four of the scenarios had reported incidence of 4-5 per year, and the expected causal factors were reported. A test of interventions to work documentation revealed that participants tended to maintain a constant level of accuracy and speed to produce this level. A Chinese translation of the document was the only significant intervention, giving about a 10% speed advantage.
The Effect of Financial Incentive on General Aviation VFR-Into-IMC BIBAFull-Text 128-130
  William Knecht
Two flight simulator studies explored the effects of financial incentive on general aviation pilots' willingness to proceed under visual flight rules flight into adverse weather. Study 1 assessed 60 pilots' takeoff behavior into varying degrees of adverse weather seen immediately at taxiway level. Thirty pilots received straight salary, while 30 received salary plus a bonus contingent on takeoff. Trend emerged in regression analysis for effect of incentive. Study 2 examined 45 pilots' in-flight continuation into weather degrading to zero visibility. Fifteen pilots received straight salary, 15 received salary plus a partial bonus, 15 received salary plus a full bonus. Bonuses were contingent on reaching the assigned destination. Although all pilots diverted before reaching the destination, financial incentive was a powerful stimulant to continuation into IMC (p = .001). The difference between studies involves an information contrast effect. That is, when conditions deteriorate slowly, a bad situation can develop unnoticed.
Influence of Graphical Metars on Pilots' Weather Judgment BIBAFull-Text 131-135
  Joseph T. Coyne; Kara A. Latorella; Carryl L. Baldwin
VFR flight into IMC conditions accounts for over 10% of general aviation fatalities each year. Recent research suggests that pilots may not properly assess weather conditions. New graphical weather information systems (GWISs) may positively or negatively influence pilot weather-related judgments. Since GWIS information is not always current it may not be veridical. In the current investigation twenty-four GA pilots made visibility and ceiling estimates of simulated weather conditions either with or without a GWIS display. Pilots generally overestimated weather conditions and their judgments were influenced by the GWIS. The results revealed an interaction between ceiling and visibility that suggests a new model for understanding VFR flight into IMC. The current results suggest an important area for future research into understanding pilots' decisions to continue into deteriorating weather conditions. Results are discussed in terms of advancing aviation decision making models for understanding VFR into IMC flight, and the design of GWIS symbology to foster accurate assessments.
Estimating Pilot Fatigue in Commercial Flight Operations BIBAFull-Text 136-139
  Jon French; Katherine Garrick
In order to assess airline pilot duty fatigue levels associated with normal operations, subjective fatigue, sleep cycles were unobtrusively monitored and compared to the estimates of a fatigue prediction algorithm (FADE). A group of 9 commercial airline pilots completed log sheets on which sleep, flight data and periodic estimates of fatigue levels were recorded over a 10-day period. The subjective fatigue scores indicated a significant increase during the 2000-0400 hours time block. The lowest reported fatigue scores occurred during the 0800-1200 hours. Hours of sleep predicted pilot fatigue levels better than circadian time, hours of flight, time zones crossed or hours of non-flying work. A fatigue-estimating algorithm (FADE) used logged sleep data and was well correlated with the subjective reports of fatigue. Use of fatigue algorithms may be useful to select the timing and crew rest considerations of commercial airline routes before they become part of normal operations.


Weather Deviation Decisions by Air Transport Crews During Simulated Flight BIBAFull-Text 140-144
  James P. Bliss; Corey K. Fallon; Ernesto A. Bustamante; William R. Bailey
As the variety and capabilities of cockpit weather displays have increased, weather deviation decisions have become more complex. Important issues include conflicting or outdated weather information, and teamed reactivity of crews to weather displays. We investigated the influence of onboard and NEXRAD agreement, range to the simulated potential weather event, and the pilot flying on collective weather deviation decisions. Twelve pilot-copilot teams flew a simulated route while reacting to weather events presented in two graphical formats on a separate visual display. Results showed that pilots often chose to deviate from weather rather than confront it. When onboard and NEXRAD displays did not agree, flight crews reacted by trusting the onboard system more but using the NEXRAD system as a backup. These results suggest that future weather displays should exploit existing benefits of NEXRAD presentation for situation awareness while retaining the display structure and logic inherent in the onboard system.
Tactile and Aural Alerts in High Auditory Load UAV Control Environments BIBAFull-Text 145-149
  Gloria L. Calhoun; Heath A. Ruff; Mark H. Draper; Brian J. Guilfoos
Tactile displays may alleviate visual workload in complex UAV control stations, cueing operators to high priority events via the haptic channel. Previous results suggest that tactile alerts (vibration on wrists) can substitute for aural alerts, as a redundant cue to visual alerts in relatively short test sessions. The present experiment investigated whether tactile alerts are advantageous in high auditory loads during longer periods of vigilance. Participants responded to events alerted via aural or tactile redundant cues, while performing multiple tasks in a simulated UAV control station. Results did not show an advantage of tactile over aural alerts in high auditory loads over 30-minute periods. Despite the lack of performance advantage of tactile alerts over aural alerts, research participants favored the tactile alerts, rating them as more salient and faster in attracting their attention.
Evaluation of Pilot Performance and Workload During Black Tube Approach to Land BIBAFull-Text 150-153
  Christopher J. Hamblin
As glass cockpits become more ubiquitous in commercial and general aviation aircraft, it is important that aircraft manufacturers consider which standby instruments should be available to the pilot if the display units (DU) should fail. This study measures pilot performance and workload while performing black tube approaches with two different standby instrument configurations. Subjective and objective measures show that: 1) Pilot's overall performance declined when using standby instruments regardless of the standby instruments provided. 2) Workload ratings were significantly lower during black tube approaches when a standby HSI was available. 3) Lateral deviations were significantly lower during black tube approaches when a standby HSI was available. These results suggest that information provided by a standby HSI is critical to pilots for performing approaches to land during black-tube operations. The HSI provides a birds-eye perspective which is critical to maintaining the pilot's situational awareness during instrument maneuvers.

AGING: Older Adults and Computer Technology

Older Adults and Attitudes Towards Computers: Have They Changed with Recent Advances in Technology BIBAFull-Text 154-157
  Sankaran N. Nair; Chin Chin Lee; Sara J. Czaja
Although the use of computers is expanding in the overall population, for older adults there still remains a "digital divide". Development of strategies to help insure that older people have equal opportunities to access computer technology depends on understanding why they have lower adoption rates. This paper examines changes in attitudes towards computers over time among a sample of 745 adults ranging in age from 18-75 yrs. Attitudes towards computers were assessed using the Attitudes Towards Computers Questionnaire across two time periods: 1994-1997 and 2000-2004. Over time, participants rated computers as less dehumanizing and reported an increased belief that computers were equally important to both genders. There were also age groups differences in ratings of comfort, efficacy, and control. The older adults reported less comfort, competence with computers. Over time, perceptions of having control over computers increased over time for the younger people but not for the middle-aged and older people. Understanding individual differences in attitudes towards computers is important to the design of intervention strategies such as training programs.
Identifying the Needs of Elderly for Technological Innovations in the Smart Home BIBAFull-Text 158-162
  Martin G. Helander; Kow Yong Ming
The study used Projective Testing techniques to identify the needs of elderly users of various features in a smart home, including: telemedicine, customized computer, teleconferencing, teleshopping, event reminder, robot helper and smart pets. Drawings of home scenarios and a male user were shown to 18 elderly users of service apartments. Altogether 192 different needs were identified. These were sorted by HF experts into broad categories. Nine categories of needs emerged relating to: Health, Communication, Security, Mobility, Mental Activities, Physical Activities, Prestige, Independence and Dependence. These were compared to needs structures documented in the literature including: Transcendent, Optimization, Anti-ageing, Dependency Avoidance and Nurturance Seeking. These needs structures are expressed at a higher level of abstraction then our nine categories. In addition the nine needs categories identified in this study can be used as a point of departure for the design of a smart home.
Older Adults and Internet Health Information Seeking BIBAFull-Text 163-166
  Tamer El-Attar; Jarvis Gray; Sankaran N. Nair; Raymond Ownby; Sara J. Czaja
The internet has created new possibilities for individuals to assume a more pronounced role in their own healthcare. This paper reports results from a study that examined the perceptions of older people of usability and trust in Internet health information. Information was also gathered on their ability to search for health information. Participants included 64 adults aged 60-82 years who were asked to answer health-related queries using websites that varied in usability. They were also asked to provide ratings of usability and of their trust in Internet health information. The results indicated that performance was lower for the "low usability" websites. Participants also rated these websites as having poorer layout, being harder to navigate, less useful and less understandable. The majority of the sample indicated that they would use the internet to find health information. These findings underscore the importance of considering usability issues when designing e-health applications.
Aging and Input Devices: Voice Recognition Performance is Slower Yet More Acceptable Than a Lightpen BIBAFull-Text 167-171
  Tiffany Jastrzembski; Neil Charness; Patricia Holley; Jeffrey Feddon
Microcomputers are ubiquitous to modern society, yet older adults consistently perform more poorly than younger counterparts using standard input devices (e.g. a mouse). Prior research has revealed that direct positioning devices (e.g. light pen), minimize age differences and enable quick transfer to the non-preferred hand. This study investigates whether speech recognition may also reduce age-related declines and enhance performance of older adults in target selection tasks. Twenty-four participants ages 20-26 (M = 21.7), twenty-four participants ages 44-55 (M = 48.9), and twenty-four participants ages 65-78 (M = 70.4) were asked to select a specified target using either a light pen or speech recognition software (IBM's Via Voice). Results revealed no age effects for type of device, but response times for target acquisition were approximately 2178 ms longer for speech recognition than the direct positioning device, and preference ratings were higher using speech as input versus the lightpen. Implications are discussed.
Examining Keyboard Shape and Arrangement Effects for Younger and Older Adults BIBAFull-Text 172-176
  Marita A. O'Brien; Wendy A. Rogers; Arthur D. Fisk
This research investigated the effects of keyboard shapes and letter arrangements for text entry with a rotary input device. In Study 1, we examined movement of a cursor across four different keyboard shapes. Shape and age had significant effects, and the interaction of the two variables was also significant. Compatibility and movement simplicity were key features of the better shapes. In Study 2, we examined visual search across three different letter arrangements on the same four shapes among the same participants. Age and arrangement were significant, but shape was not. Only the shape by arrangement interaction was significant, so the benefit of arrangement familiarity may be limited to specific virtual keyboard shapes.

AGING: Exploring Age Differences in Kinematics, Perception, and Cognition

Differences in Trunk Kinematics and Ground Reaction Forces Between Older and Younger Adults During Lifting BIBAFull-Text 177-181
  Gwanseob Shin; Mack L. Nance; Gary A. Mirka
Trunk kinematics, ground reaction forces, and the motion of the center of pressure (COP) of older and younger subjects were compared in lifting to study age-related differences between the two age groups. Ten older (55 63 years old) and ten younger (19 29 years old) adults performed lifting tasks under six different conditions; three destination heights and two asymmetry angles of origin. Subjects' trunk kinematics, ground reaction forces and COP motions were measured by the Lumbar Motion Monitor (LMM) and a force plate. Older subjects showed significantly less trunk kinematics, peak ground reaction forces, and COP motions than younger subjects, indicating older subjects chose more stable lifting strategy and it might compensate for the decreased ability of postural control over age. Less ground reaction forces and motion of COP suggested that risks of falls and slips of older subjects were less than younger subjects.
Age Differences in the Useful Field of View during Real-World Driving BIBAFull-Text 182-185
  Frank Schieber; Jess Gilland
Age differences in the useful field of view (UFOV) were assessed during real-world driving using a newly developed car-following protocol. Nineteen young (mean age = 23) and 19 older (mean age = 73) drivers were examined. Peripheral target detection performance declined significantly with age and target eccentricity. However, consistent with several recent studies, no age by target eccentricity interaction was observed. These findings contribute to the validation of the UFOV construct and provide a foundation for better understanding age-related changes in visual attention in the real-world driving domain.
Designing External Aids That Support Older Pilot Performance BIBAFull-Text 186-189
  Daniel Morrow; Dervon Chang; Christopher Wickens; Esa Rantanen; Liza Raquel
Communication taxes pilots' cognitive resources. External aids such as note-taking help pilots manage these demands. Morrow et al. (2003) found that note-taking eliminated age differences among pilots on a readback task compared to a no-aid condition. However, we investigated communication-only rather than multi-task environments typical of piloting. The present study compared note-taking (kneepad) with an electronic notepad positioned next to the instrument panel in a flight simulator (epad). The epad may be easier to coordinate with concurrent tasks because it is more integrated with flight instruments. Six older and six younger pilots used these aids to respond to ATC messages in a flight simulator. Readback accuracy was higher when pilots used either aid compared to a no-aid condition. The pattern of results suggested a smaller age difference in the aid than in the no-aid conditions. The results replicate the earlier finding of note-taking benefits and extend them to the novel epad.
Age-Related Differences in Learning Incidental Environmental Information BIBAFull-Text 190-194
  Kelly E. Caine; Timothy A. Nichols; Arthur D. Fisk; Wendy A. Rogers
Incidental environmental information is consistent, potentially beneficial, information that is not necessary for successful task performance (i.e., is seemingly unrelated to the task). In the present study, older and younger participants searched for target letters among distractor letters both of which were laid upon color environments, such that certain color environments predictively correlated with target letter location at varying degrees of consistency. Neither group could express verbal knowledge of the pattern of the environmental information although younger but not older adults showed improved performance in conditions where incidental information cued target location. The findings suggest that younger adults can benefit from incidental environmental information even when they cannot express that it is present in a task but that older adults may need additional cues to benefit from the information.
Relational and Metaphorical Approaches to Information Visualization: Effects of Age and Graphical Facility BIBAFull-Text 195-199
  Mark D. Lee; Lena Mamykina; Chandra Harrison
Diabetes requires continual monitoring of diet, glucose level, and other personal data so that a balance may be achieved between a desired lifestyle and one that is healthy and sustainable. While ubiquitous computing technologies can capture data necessary to make judgments, individuals need to be able to easily comprehend the data to draw conclusions. To help individuals with diabetes with this task, we designed two types of visualizations, a relational visualization using traditional graph-based techniques for presenting data, and a metaphorical visualization that conveys data using familiar, domain-specific imagery in an aesthetically pleasing composition. This paper presents a comparative analysis of these visualizations which indicated that older individuals with lower general graph-interpretation skills perform superior data analysis when using a visualization based on a familiar metaphor. These findings suggest that metaphorical visualizations constitute a viable alternative when designing informational displays for the elderly.

AGING: Posters

Age Differences in Search Time for Two Over-the-Counter (OTC) Drug Label Formats BIBAFull-Text 200-203
  Christina C. Mendat; Aaron M. Watson; Christopher B. Mayhorn; Michael S. Wogalter
This study compared older and younger adults' knowledge acquisition and search times for information on older and newer over-the-counter (OTC) drug label formats. The results showed that younger adults were faster than older adults. The younger group performed significantly faster with the newer formatted labels than the older formatted labels, whereas the older adults yielded no difference between the two formats. Potential directions for future research are discussed.
An Empirical Study of the Ergonomic Design of Pill Bottle Caps for the Elderly BIBAFull-Text 204-208
  Jennifer M. Ross
A central requirement of designing pharmaceutical is designing for the elderly and those with poor manual dexterity (e.g., arthritis); however, in an effort to reduce the number of accidental poisonings in children each year it is vital to make pharmaceutical containers child resistant. This study entails an empirical examination of several commonly used child resistant containers (CRCs) across younger (≤35) and older adults (≥50). Results indicated that both younger and older adults could use the containers. However, results did differ on task completion times and rates of perceived exertion for bottle cap design, which was dependent upon both bottle size and CRC design. Design recommendations were made, to employ larger bottles with CRC designs that emphasize mental over physical dexterity (i.e., align-arrow cap design) and smaller more easily managed bottles with CRC designs that emphasize physical dexterity (i.e., push and twist cap design).
Package Opening: An Evaluation of Opening Tools for the Elderly Population BIBAFull-Text 209-213
  Chaitanya Saha; Randa L. Shehab
Opening packages is becoming more difficult with manufacturers making packaging harder to tamper with. Consumers must apply greater force or use tools to aid them in opening. With aging, the amount of force that can be applied reduces considerably which makes it important to view the packaging problem from the perspective of the older population. The objective of the current study was to determine the effectiveness of opening tools in opening different kinds of packages. The study revealed that the tools are mostly ineffective and do not improve performance beyond the use of the hands alone. In addition, the more complex the tool, the less effective the tool was as an aid to open packaging.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Task Analysis for Design and Explanation

The Impact of Meta-Information on Decision-Making in Intelligence Operations BIBAFull-Text 214-218
  Jonathan Pfautz; Adam Fouse; Ted Fichtl; Ann Bisantz; Emilie Roth; Samuel Madden
Decision-making in complex, dynamic, high-risk environments is clearly challenging. Part of this challenge is due to the presence of qualifiers of information, or meta-information (e.g., staleness, uncertainty, source), that alter a person's information processing, situational awareness, and decision-making. We investigated the influence of meta-information on decision-making in a Military Intelligence Operations (IO) environment using Cognitive Task Analysis (CTA) techniques. We performed a CTA on IO tasks surrounding the use of smart sensor webs, a relatively new technology that can be used for a variety of IO purposes. Our analysis addressed information management tasks and tactical decision-making tasks using sensor webs. We discovered that a variety of types of meta-information significantly impacted decision-making, and that the influence of meta-information was both context-and task-sensitive. In this paper, we present the results of the CTA and discuss the implications for the development of decision-aiding systems, including the design of constituent displays, interfaces, and automated systems.
Applying a Dynamic Model of Situated Cognition to the Investigation of Mishaps BIBAFull-Text 219-223
  Nita Lewis Miller; Lawrence G. Shattuck
Complex systems will, inevitably, experience failures. The cause of these failures or mishaps may be labeled 'operator error,' but often they are actually caused by the confluence of technological, situational, individual, and organizational factors. Several models and theories of human error have been proposed over the years and are reviewed in this paper. The authors propose another model, the Dynamic Model of Situated Cognition (DMSC), to explain how complex systems fail. Miller and Shattuck (2004) developed the DMSC in an effort to link technological aspects of a system to the perceptual and cognitive aspects of that system. They illustrated the model by applying it to the USS Stark incident and to a military command and control simulation (Shattuck and Miller, 2004). The model also appears to have utility as a retrospective explanatory tool to identify when and where things went wrong. In this paper, the authors describe the DMSC as it relates to the analysis of error in complex systems and apply it to the February 2001 mishap in which the U.S. Navy submarine USS Greeneville collided with the Japanese motor vessel Ehime Maru off the coast of Oahu, Hawaii.
Using a Reconstruction-Exploration Approach to Empower Cognitive Analysis Methods: Possibilities and Challenges BIBAFull-Text 224-228
  Par-Anders Albinsson; William Wong; Sofie Pilemalm; Magnus Morin
One problem in analyzing large-scale, distributed tactical operations is to get an overview of the operation to guide the interpretation of data collected. Cognitive analysis methods, such as the critical decision method, do generally not focus on reconstructing detailed models of the work sessions, but rather on summarizing particular incidents based on retrospective interview data and self-reports. The existing reconstruction-exploration approach involves the construction and presentation of time-synchronized, event-driven multimedia models of the course of events from distributed operations. It does not, however, provide systematic analysis methods. This paper discusses the possibilities and challenges of integrating the critical decision method and the reconstruction-exploration approach to arrive at a complementary solution.
Achieving Cyber Defense Situational Awareness: A Cognitive Task Analysis of Information Assurance Analysts BIBAFull-Text 229-233
  Anita D'Amico; Kirsten Whitley; Daniel Tesone; Brianne O'Brien; Emilie Roth
A Cognitive Task Analysis (CTA) was performed to investigate the workflow, decision processes, and cognitive demands of information assurance (IA) analysts responsible for defending against attacks on critical computer networks. We interviewed and observed 41 IA analysts responsible for various aspects of cyber defense in seven organizations within the US Department of Defense (DOD) and industry. Results are presented as workflows of the analytical process and as attribute tables including analyst goals, decisions, required knowledge, and obstacles to successful performance. We discuss how IA analysts progress through three stages of situational awareness and how visual representations are likely to facilitate cyber defense situational awareness.
Identifying Decision Complexity Factors in Ambulance Command and Control BIBAFull-Text 234-238
  J. Hayes; A. Moore; G. Benwell; B. L. W. Wong
To understand the decision making processes of fourteen ambulance command and control (C2) operators, interviews employing the critical decision method were conducted in two ambulance C2 centres. An emergent themes analysis of the interview transcripts resulted in the identification of the strategies used by the operators when making dispatch decisions. To complement this work, factors that were considered to contribute to the complexity of the decision making task were identified and then rated by the operators to determine the extent of this contribution. As a result the researchers obtained quantitative data regarding the factors that were considered to contribute the greatest to the complexity of the dispatch task from the view point of the operators. The benefits of this approach include the identification of cognitive 'choke points' in the dispatch process that can be addressed during interface design.

COGNITIVE ENGINEERING AND DECISION MAKING: Contemporary Issues in Cognitive Engineering

Integration of Cognitive Requirements into System Design BIBAFull-Text 239-243
  Gavan Lintern
The products of cognitive analysis are rarely used effectively in the design of complex, first-of-a-kind systems. This project is motivated by the assumption that those products do not explicitly reveal their design the implications. On the other hand, the analyses undertaken by Systems Engineers do not capture the essential properties of cognitive requirements. The work described here is aimed at developing a computer-supported system that can support dialog between Cognitive Engineers and Systems Engineers as they seek to resolve design issues surrounding cognitive requirements. This project is in its first phase. The preliminary work has demonstrated how a Brahms model might be used to develop a prototype of a socio-technical system based on cognitive specifications developed from a Work Domain Analysis.
Envisioning Evolvable Work-Centered Support Systems: Empowering Users to Adapt Their Systems to Changing World Demands BIBAFull-Text 244-248
  Ronald Scott; Emilie Roth; Stephen Deutsch; Samuel Kuper; Vincent Schmidt; Mona Stilson; Jeffrey Wampler
Work-Centered Support Systems (WCSS) provide visualizations that reveal domain constraints and affordances based on software agent technology to support cognitive and collaborative work. Here we argue for a need to incorporate facilities that enable users to adapt these systems to the changing requirements of work -- evolvable work-centered support systems. We recently developed a WCSS for weather forecasting and monitoring in an airlift organization that is currently used in their operations center. As part of the development process we conducted field observations both prior and subsequent to system introduction. A striking finding was the constant changes that operations personnel faced (changes in goals and priorities; changes in scale of operations; changes in team roles and structure; changes in information sources and systems). We describe the changes in workplace demands that we observed and the modifications we needed to make to the WCSS in response. Our findings are presented as a case study to illustrate the challenges confronted in designing a WCSS to support a constantly changing environment. For today's fielded systems, making changes that are responsive to users changing requirements in a timely manner is seldom possible.
Theoretical Concepts for Work Domain Analysis, the First Phase of Cognitive Work Analysis BIBAFull-Text 249-253
  Neelam Naikar
Cognitive work analysis (CWA) is gaining recognition as a promising approach for the analysis, design, and evaluation of complex, sociotechnical systems. However, the successful and widespread application of work domain analysis (WDA), the first phase of CWA, is limited by the lack of a coherent theoretical approach. This paper addresses a number of theoretical issues relating to WDA, including differences in the approaches of Rasmussen, Pejtersen & Goodstein (1994) and Vicente (1999), and it illustrates these theoretical issues with a work domain of a home -- a 'system' that will be highly familiar to everyone. This research will help to: make WDA more accessible to researchers and practitioners who were not involved in the development of WDA or who cannot be apprenticed to experts in WDA; reduce the amount of time and effort it takes to perform WDA even for experts in the area; and facilitate the application of WDA to large-scale, industry projects.
Cognitive System Engineering -- Based Design: Alchemy or Engineering BIBAFull-Text 254-258
  James W. Gualtieri; Samantha Szymczak; William C. Elm
Cognitive Systems Engineering (CSE) techniques are widely used for the description and analysis of the sources of cognitive complexity and explicating the basis of expertise within a work domain. However, the results of the CSE techniques often focus on work analysis and are only weakly coupled to the design of decision support systems that are built based on those analyses. In fact, some within the CSE community have suggested that such a design epiphany occurs as if by magic. If CSE is to be treated as an engineering discipline, it cannot rely on magic to create systems. The approach described in this paper assumes that an explicit relationship between system design and supported cognitive work is fundamental to the design's effectiveness. The goal is a pragmatic, effective engineering process that explicitly designs systems according to relationships between cognitive work requirements and decision support concepts.
From Information Content to Auditory Display with Ecological Interface Design: Prospects and Challenges BIBAFull-Text 259-263
  Penelope M. Sanderson; Marcus O. Watson
We examine how Ecological Interface Design (EID) might better bridge the gap from analysis to design by taking different modalities into account. Whereas almost all previous research using EID has focused on visual displays, attempts to extend the use of EID to non-visual modalities have revealed hidden assumptions that need to be made explicit and questioned. In this paper we explore the potential for EID to support a systematic process for the design for auditory displays, illustrating our argument with the design of auditory displays to support anaesthesia monitoring. We propose a set of steps that analysts might take to move more deliberatively and effectively from analysis to design with EID.

COGNITIVE ENGINEERING AND DECISION MAKING: Military Team Communications, SA, and Cognitive Modeling

Paintball 2: A Study of Remote-Controlled Vibro-Tactile Stimulation for the Simulation of Leader Presence BIBAFull-Text 264-268
  Kip Smith; Martin Liberg
At the HFES meeting in Denver we discussed experiments that documented a consistent decrement in performance associated with remote command and control (Pangburn, Freund, Pangburn, & Smith, 2003). The venues for these experiments were paintball assault lanes. Our participants were slower to obey verbal orders given by a remote leader than by a leader who was physically present. We have subsequently shown that the delay is due to the lack of leader presence and not to reliance upon mediated communication (Smith, 2004). Here we discuss an experiment that tests the hypothesis that gentle remote-controlled vibro-tactile stimulation by a remote leader can compensate for the observed decrement. The data encourage us to suggest that it would be prudent to evaluate further the effectiveness of remote-controlled vibro-tactile stimulation prior to finalizing plans for remote command and control of the dismounted infantry.
Cognitive Model of Team Collaboration: Macro-Cognitive Focus BIBAFull-Text 269-273
  Norman Warner; Michael Letsky; Michael Cowen
The purpose of this paper is to describe a cognitive model of team collaboration emphasizing the human decision-making processes used during team collaboration. The descriptive model includes the domain characteristics, collaboration stages, meta- and macro cognitive processes and the mechanisms for achieving the stages and cognitive processes. Two experiments were designed to provide empirical data on the validity of the collaboration stages and cognitive processes of the model. Both face-to-face and asynchronous, distributed teams demonstrated behavior that supports the existence of the collaboration stages along with seven cognitive processes.
Coordinated Awareness of Situation by Teams (CAST): Measuring Team Situation Awareness of a Communication Glitch BIBAFull-Text 274-277
  Jamie C. Gorman; Nancy J. Cooke; Harry K. Pederson; Olena O. Connor; Janie A. DeJoode
A coordination-based measure of team situation awareness is presented and contrasted with knowledge-based measurement. The measure is applied to team awareness of a communication channel failure (glitch) during a simulated unmanned air vehicle reconnaissance experiment. Experimental results are reported, including the findings that not all team members should be identically aware of the glitch and that appropriate levels of coordination are an important precursor of team situation awareness. The results are discussed in terms of the application of coordination metrics to support the understanding of team situation awareness. The use of team coordination as a low-dimension variable of team functionality is scalable over a variety of team sizes and expertise distributions.
An examination of situation awareness and confidence within a distributed multinational coalition BIBAFull-Text 278-282
  Frederick M. J. Lichacz
A simulated conflict resolution scenario was conducted to assess the effectiveness of a new military force structure called Effects Based Operations (EBO). This paper reports on the ability of an instantiation of an EBO approach to facilitate team SA, and the calibration of confidence and SA among members of a multinational coalition during this simulation.
Change Blindness: Detecting Icon Position Change in Military Information Displays BIBAFull-Text 283-286
  Amy Rodriguez; Jennifer Jantzi; Daniel R. Smith
Designers of military systems, such as Force XXI Battle Command Brigade and Below (FBCB2), are concerned that "change blindness" may cause users to miss information updates. In the current study, participants monitored an FBCB2 display and reported the changes they detected. Results indicate that participants were not more likely to detect icon position changes (moves), when they were large, 17.5 mm moves (control moves), opposed to when they were gradual moves (a series of 10 smaller, 1.75 mm moves). But, when moves were correctly detected, response times were faster for control moves than they were for gradual moves. These findings may help clarify how attributes of a change (here, gradual vs. control moves) influence change blindness in military information displays.

COGNITIVE ENGINEERING AND DECISION MAKING: Decision Aiding in Military and Intelligence Systems

An Assessment of Weasel: A Decision Support System to Assist in Military Planning BIBAFull-Text 287-291
  Adam D. Larson; Caroline C. Hayes
This work describes an experiment analyzing the use of a decision support system, Weasel, and its impact on military decision makers' performance. Decision support systems (DSSs) are computer tools that assist people in making better decisions without necessarily making those decisions for them. Weasel is a DSS designed to assist military planning staff in generating enemy courses of action (ECOAs) for ground forces. Because of the increased complexity and tempo of modern operations, there is great interest in development and use of decision support systems in critical decision making tasks. Critical decision making tasks are those that may have safety, financial, or political consequences. Thus, it is important to clearly understand both the positive and negative impacts that a DSS can have on human decision making before adopting such a tool. Positive impacts can include: broader exploration of the solution space, increased solution quality, and reduced problem solving time. Negative impacts can include increased training and data entry time, over-reliance (i.e. inappropriate trust on a DSS is a major concern in safety critical domains (Parasuraman, 1997)) on the computer tool and increased work-load, to name a few.
Performance of Individuals and Groups in Sensemaking of Information from Computer Decision Aiding Systems BIBAFull-Text 292-296
  Celestine A. Ntuen
This study presents preliminary results of a comparison of the manner in which individuals and a group of decision makers make sense of computer-aided information. Experiments were conducted to analyze the differences between individuals and a group of sense makers with respect to their perceptions of decision aiding information using Weick's sensemaking dimensions. The group of decision makers tended to grasp situations in more detail, use consensus in validating computer-aided information, adapt to new information more readily, and pay more attention to automation reliability. On the other hand, the individuals tended to assimilate decision-aided information into practice and to use cues from automation, and pay attention to the practical use of automated information.
Finding Decision Support Requirements for Effective Intelligence Analysis Tools BIBAFull-Text 297-301
  William Elm; Scott Potter; James Tittle; David Woods; Justin Grossman; Emily Patterson
Within ARDA's GI2Vis program, we developed a unique framework for the definition of decision support requirements for intelligence analysis tools. This framework, based on a first-of-a-kind integration of a model of inferential analysis and principles for designing effective human-computer teams from Cognitive Systems Engineering, has defined the essential support functions to be provided to the intelligence analyst(s). This model has proven to be extremely useful in assessing the support provided by a large set of visualization tools. This assessment has identified clusters of support functions that are addressed by many tools as well as key missing support functions. In this way, the Support Function Model has been used to identify gaps in the support function coverage of existing tools. This can serve as a valuable focusing mechanism for future design and development efforts. In addition, we believe this would be a useful mechanism to enhance cross-discussions among research teams involved in Cognitive Task Analysis efforts within the Intelligence Community. Having others integrate their analytic results with this framework would provide the mechanism for expansion of this model to become a more robust tool and have an even greater impact on the Intelligence Community.
Event Template Hierarchies as Means for Human-Automation Collaboration in Security Surveillance BIBAFull-Text 302-306
  David Woods; Stephanie McNee; James W. Davis; Alexander Morison; Patrick Maughan; Klaus Christoffersen
Advances in remote sensing systems provide human monitors access to more data. The current challenge is to help extract relevant patterns and direct the attention of human monitors and human problem holders to the changing security picture with respect to acute situations (a normal market scene turns into an ethnic confrontation) or longer term trends (seeing new patterns of 'typical' behavior to avoid false alarms). Security surveillance monitoring can be advanced through new event recognition capability of autonomous monitors and by effectively coupling these sensor/algorithm systems to human monitors and problem holders. To meet these challenges in security surveillance, we have developed an event-sensitive architecture where machine agents provide event-based information to human monitors and problem holders and are re-directable given contextual information. The key innovation is a context-based hierarchical event template structure which can be used to integrate data over a distributed sensor system.
Adaptive Change in the Type of Automation Support Reduces the Cost of Imperfect Decision Aids in a Simulated Battlefield Engagement Task BIBAFull-Text 307-311
  Kathleen McGarry; Ericka Rovira; Raja Parasuraman
Automation that is meant to aid the human operator may actually be detrimental to performance, particularly if faulty decision recommendations are provided (decision automation), as opposed to prioritized or integrated information advisories that are incorrect (information automation). Because automation can be imperfect, operator over-reliance on decision automation can degrade performance. The present study examined whether temporary adaptive changes in the type and level of automation -- between decision and information automation, or between decision automation and manual performance -- could mitigate the cost of automation imperfection in a combat engagement selection task. Twelve participants were provided with two types of automation (decision and information) and also performed the task manually. In three conditions, the type of automation was alternated during performance of the task over three blocks of trials. In all three conditions, decision automation was provided in the first and third blocks of the task, with the middle block requiring the use of decision automation, information automation, or manual performance. The accuracy of engagement decisions improved in the third block with decision automation when it was preceded by a temporary adaptive change to information automation. No such improvement occurred when decision automation was used throughout the task or when the adaptive change involved a temporary return to manual performance. This suggests that providing the user with short periods of information automation can help mitigate some of the costs of imperfect decision automation by keeping the operator in the decision-making loop.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Systems Engineering and Work Analysis

A Methodology for Work Domain Analysis, the First Phase of Cognitive Work Analysis BIBAFull-Text 312-316
  Neelam Naikar
Cognitive work analysis (CWA) is gaining recognition as a promising approach for the analysis, design, and evaluation of complex, sociotechnical systems. The successful and widespread application of CWA, however, is limited by the lack of a well-defined methodology. This paper proposes a methodology for performing work domain analysis (WDA), the first phase of CWA, and it illustrates this methodology with a work domain of a home -- a 'system' that will be highly familiar to everyone. This research will help to: make WDA more accessible to researchers and practitioners who were not involved in the development of WDA or who cannot be apprenticed to experts in WDA; reduce the amount of time and effort it takes to perform WDA even for experts in the area; and facilitate the application of WDA to large-scale, industry projects.
Generic Support Requirements for Cognitive Work: Laws that Govern Cognitive Work in Action BIBAFull-Text 317-321
  David Woods
Research in Cognitive Systems Engineering (CSE) has successfully identified basic requirements that must be met if new technology will be useful to practitioners in context. Synthesizing these basic requirements or support functions is part of a process of debate and consolidation of the foundations of the field after 25 years of productive activity (Klein, 1999; Endsley et al., 2003; Hollnageland Woods, 2005). This work takes the "Laws that Govern Cognitive Work" which synthesize basic findings and patterns (Woods, 2002; Hoffman and Woods, 2005) and provides the next step-a set of basic requirements or support functions for design. General requirements for effective support can be used to jump start individual development projects in any domain. Debating how to achieve these support functions helps translate the insights of cognitive work analyses into tangible new uses of technological possibilities.
Decision-Centered Testing (DCT): Evaluating Joint Human-Computer Cognitive Work BIBAFull-Text 322-326
  Robert Rousseau; James Easter; William Elm; Scott Potter
In order to test the effectiveness of a human operator paired with a decision support system, it is necessary to complement current testing practices addressing software validation, human performance, and usability. Decision Centered Testing (DCT) aims at testing the effectiveness of operators teamed with Decision Support Systems (DSS) in any challenging work domain. DCT is grounded in a Cognitive Systems Engineering (CSE) framework, where the concept of a joint cognitive system (JCS) is central. DCT aims at evaluating the decision-making effectiveness across identified 'error prone' regions in the JCS structure. A description of the DCT Methodology with an illustration taken from an initial application of the methodology is presented. In this application, insights from the DCT methodology enabled the definition of appropriate test metrics and the construction of unique test scenarios to exercise the decision-making effectiveness. From this application, it can be concluded that following the DCT Methodology facilitated the construction of an evaluation framework for assessing JCS net decision-making effectiveness.
Application of a Work-Centered Design Method to Support Counterspace Operations BIBAFull-Text 327-331
  Michael Szczepkowski; Kelly Neville; Ed Popp
A number of challenges hinder the development of systems that support users in the conduct of their work. Challenges include the widespread use and acceptance of design methods that are system-centered rather than work-centered; the time required to develop a work-centered system design; the imprecise nature of translating work domain analysis results into a work-centered design; and unsatisfactory means for coordinating design and design-implementation processes. The Work-centered Infomediary Layer (WIL) design model and method have been developed to address challenges such as these and to facilitate work-centered design in general. In this paper, we describe the application of WIL to the design of a work-centered support system for defensive counterspace (DCS) operators. The design model and method are presented, followed by a description of the resulting system design and ways in which it was shaped and defined through use of the WIL method.
Conveying Work-Centered Design Specifications to the Software Designer: A Retrospective Case Analysis BIBAFull-Text 332-336
  Robert G. Eggleston; Emilie Roth; Randall Whitaker; Ron Scott
It has been noted that there is a gap between the analysis and products produced by cognitive engineers (CEs) and what is needed by software engineers who must implement CE-based requirements in the final product medium. In this paper, we report on a retrospective analysis of intermediate design artifacts that were produced from a CE and work-centered design perspective during the course of developing a successful work-centered support system software application. The analysis involved an examination of design analysis and synthesis artifacts produced by the development team that were made available to the software engineers. It concentrated on how work-centered information and requirements were conveyed and made useful to the software engineering staff. Based on this analysis, we suggest that a work-centered specification package needs to contain at least three classes of information: (1) work-centered descriptions of the work context, work activity, and support requirements, (2) principles and guidance specifying "work centeredness" and (3) detailed specifications of the aiding solution with links back to the support requirements.

COGNITIVE ENGINEERING AND DECISION MAKING: Information Processing, and Information and Feedback Displays

Multimodal Working Memory: The Unfolding Story BIBAFull-Text 337-341
  Shatha N. Samman; Valerie Sims; Kay M. Stanney
Given the prevalence of information overload, it is essential that systems are designed utilizing multiple communication media. Wickens' (1984) Multiple Resource Theory (MRT) suggests that performance efficiency may be realized via multiple sensory, processing, and response modalities. Recently, modality-specific working memory (WM) subsystems have been proposed, which include verbal, visual, spatial, kinesthetic, tactile, and tonal components. However, it has yet to be determined if modality-specific subsystems exhibit separate systems with their own resources, or if all or a subset of these systems shared certain resources in a global WM unit. The purpose of this study was to examine if the modality-specific subsystems were indicative of separate WM resources or shared common resources. Results demonstrated no interference between modality-specific subsystems, suggesting that they pull from separate WM resource pool. These findings support the expansion of the MRT to a multimodal WM processing system and great promise for multimodal design.
Effects of Cognitive Functioning on Strategic System Engineering BIBAFull-Text 342-346
  Michael Goings; Stephen A. Cyr; Steve Hall; Shawn Doherty
Mental workload is an important construct in psychology. Using various methods, researchers have investigated ways to reduce the amount of workload imposed on system operators. Reducing workload through system design might be facilitated by identifying required cognitive resources and designing the system so that tasking does not impose resource conflict which may cause a decrement in performance. Wickens' multiple-resource theory has expanded on the three stages of processing (encoding, central-processing, and responding) to include cognitive resources, such as visual/spatial encoding, spatial/abstract processing, and manual discrete and non-discrete responding resources which are identified in this model. This study represents a first step towards building a research paradigm in which the amount of resource conflict (resulting in performance decrements) is estimated by taxing multiple resources simultaneously.
Effects of Visual and Auditory Cues about Threat Location on Target Acquisition and Attention to Auditory Communications BIBAFull-Text 347-351
  Monica M. Glumm; Kathy L. Kehring; Timothy L. White
This laboratory study examined the effects of visual, spatial language, and 3-D audio cues about target location on target acquisition performance and the recall of information contained in concurrent radio communications. Two baseline conditions were also included in the analysis: no cues (baseline 1) and target presence cues only (baseline 2). In modes in which target location cues were provided, 100% of the targets presented were acquired compared to 94% in baseline 1 and 95% in baseline 2. On average, targets were acquired 1.4 seconds faster in the visual, spatial language, and 3-D audio modes than in the baseline conditions, with times in the visual and 3-D audio modes being 1 second faster than those in spatial language. Overall workload scores were lower in the 3-D audio mode than in all other conditions except the visual mode. Less information (23%) was recalled from auditory communications in baseline 1 than in the other four conditions where attention could be directed to communications between target presentations.
Information Layering, Depth and Transparency Effects on Multi-Layered Displays for Command and Control BIBAFull-Text 352-356
  B. L. William Wong; Ronish Joyekurun; Anna Nees; Paola Amaldi; Rochelle Villanueva
This paper reports on research into development of techniques for information representation in complex dynamic environments, such as those with high information densities, and with high rates of change. These design techniques employ information layering, visual depth and transparency to present informationi in the new Multi-Layered Display (MLD) technology, in anticipation that their combined use can improve information uptake in such environments. The results show that there is no advantage in using the MLD in simple reading and interaction tasks. However, user performance was observed to be significantly better when using layering techniques on the MLD under increased task difficulty conditions that approximate information handling challenges in command and control activities.
Melioration Despite More Information: The Role of Feedback Frequency in Stable Suboptimal Performance BIBAFull-Text 357-361
  Hansjorg Neth; Chris R. Sims; Wayne D. Gray
Situations that present individuals with a conflict between local and global gains often result in a behavioral pattern known as melioration -- a preference for immediate rewards over higher long-term gains. Using a variant of a paradigm by Tunney & Shanks (2002), we explored the potential role of feedback as a means to reduce this bias. We hypothesized that frequent and informative feedback about optimal performance might be the key to enable people to overcome the documented tendency to meliorate when choices are rewarded probabilistically. Much to our surprise, this intuition turned out to be mistaken. Instead of maximizing, 19 out of 22 participants demonstrated a clear bias towards melioration, regardless of feedback condition. From a human factors perspective, our results suggest that even frequent normative feedback may be insufficient to overcome inefficient choice allocation. We discuss implications for the theoretical notion of rationality and provide suggestions for future research that might promote melioration as an explanatory mechanism in applied contexts.

COGNITIVE ENGINEERING AND DECISION MAKING: Good Design Ideas Gone Bad: Lessons Learned When System Designs Do Not Work as Planned

Good Design Ideas Gone Bad: Lessons Learned When System Designs Do Not Work as Planned BIBAFull-Text 362-365
  Patricia L. McDermott; Cheryl Bolstad; Greg Jamieson; Lila Laux; Lawrence Shattuck; Christopher Wickens
If at first you don't succeed, try again. Often the first or second design alternatives are modified or discarded based on preliminary evaluation. However, there is much to be learned from design ideas that did not work as planned. Unfortunately, the lessons learned from these inadequate designs are not always shared within the human factors community. This panel provides a forum to share the lessons learned by panelists who are actually creating and evaluating designs in the field. The panelists represent a balance of perspectives from academia, industry, and government. Attendees should come away from the session with concrete examples of inadequate interface designs, how they were improved, and an understanding of why the design did not work for a particular application. A successful panel will create a forum to share lessons learned and perhaps prevent practitioners from repeating work that has already been done.

COGNITIVE ENGINEERING AND DECISION MAKING: Transportation Systems and Human Performance

A Cognitive Engineering Approach for Facilitating Analysis of Human-Computer Interaction in Complex Work Domains BIBAFull-Text 366-370
  Wei Xu
This paper demonstrates that work domain analysis (WDA), a cognitive engineering approach based on Rasmussen's abstraction hierarchy (AH) framework, is a valuable and alternate analytic tool for analyzing human-computer interaction (HCI) in complex work domains through a case study. In the case study, we use WDA to examine automation awareness, an HCI issue in automated flight decks. The case study shows that WDA provides an effective approach to systematically assess collected human factors data in order to identify the gaps in satisfying the work requirements across interrelated factors. It helps assess the adequacy of domain information provided to workers via training in order to build a fairly accurate and effective mental model, adequacy of domain information presented to workers at the interface, and the adequacy of operation procedures designed for workers to copy with unfamiliar situations. Finally, WDA also helps generate needs for enhancements of existing systems from a work domain perspective.
Pilots Perceptions and Retention of In-Flight Upset Recovery Training: Evidence for Review and Practice BIBAFull-Text 371-375
  Janeen A. Kochan; Eyal G. Breiter; Matthew B. Hilscher; James E. Priest
Loss-of-control in fight was largest category of fatal commercial air carrier accidents between 1994 and 2003 (Boeing Commercial Airplanes Group, 2004). Loss-of-control accidents were also the leading cause of general aviation accidents in the U.S. in 2003 (AOPA Air Safety Foundation, 2004). These accidents have been on the constant increase for all categories of flight, for the past 25 years. In response to this issue, The Flight Research Training Center was established, in cooperation with the Federal Aviation Administration (FAA), to provide specific training for pilots on dealing with upset events that can lead to loss-of-control. This paper presents the initial results of an ongoing, longitudinal study investigating (a) user satisfaction, (b) pilots' subjective perceptions, and (c) the pilots' knowledge and procedure retention level of the elements of an upset recovery training program. Suggested protocols and methods to improve the durability of the knowledge and skills learned in the training program are offered.
Contributing Factors for Mode Awareness of a Vehicle with a Low-Speed Range and a High-Speed Range ACC Systems BIBAFull-Text 376-380
  Makoto Itoh; Toshiyuki Inagaki; Yasuhiro Shiraishi; Takayuki Watanabe; Yasuhiko Takae
This paper tries to clarify contributing factors to achieving driver's mode awareness while he or she is driving a vehicle with a low-speed range and a high-speed range Adaptive Cruise Control (ACC) systems. We investigate the following three probable factors: (1) control logic for a low-speed range ACC when it loses sight of the target vehicle to follow, (2) previous acquaintance with the high-speed range ACC, and (3) control mode utilized more frequently. An experiment has been conducted with a fixed-based driving simulator to investigate effects of these factors on the driver's mode awareness.
Situation Awareness in Driving While Using Adaptive Cruise Control and a Cell Phone BIBAFull-Text 381-385
  Ruiqi Ma; Mohamed A. Sheik-Nainar; David B. Kaber
This research investigated the effects of an adaptive cruise control (ACC) system, and cell phone use in driving, on a direct objective measure of situation awareness (SA). Subjects drove a virtual car in a medium-fidelity driving simulation and performed a following task. Half of the subjects were required to respond to cell phone calls and all subjects completed trials with and without use of the ACC system. SA was measured using a simulation freeze technique and SA queries on the driving situation. Results indicated use of the ACC system to improve driving task SA under normal driving conditions, and cell phone conversations degraded SA. Results also revealed the ACC system to improve safe driving headway distance. Although the deviations in headway distance from an optimum were greater during cell phone conversations, this did not prove to be significant in terms of performance under normal driving conditions.


Advances in Human-Robot Interaction BIBAFull-Text 386
  Susan Archer; Patricia L. McDermott
Robotic assets are increasingly utilized in tasks such as search and rescue operations, military reconnaissance, and space station repairs. It is helpful to view the robot as a team member and determine what communication styles, task configurations, interfaces, and robotic characteristics are necessary for effective human-robot interaction. The underlying theme in the symposium is the investigation of cognitive aspects of human-robot interactions and the implications for interface design, training, or organizational design. Three phases of human-robot interaction will be discussed. The first identifies team dynamics such as the situation awareness requirements. The second determines which supervisory control interfaces lead to optimal human-robot performance. The third helps operators to understand the information provided by robots and to communicate that information to those who need it. Ms. Susan Archer, Director of Operations at Micro Analysis & Design and Consortium Manager of the Army Research Laboratory Advanced Decision Architectures Collaborative Technology Alliance, will summarize themes and discuss future directions of Soldier-robot teaming in Future Combat Systems.
The Impacts of Multiple Robots and Display Views: An Urban Search and Rescue Simulation BIBAFull-Text 387-391
  Roger A. Chadwick
The use of remote controlled uninhabited ground vehicles (UGVs) is expanding in military and emergency operations. In operations involving multiple UGVs controlled by a single operator, understanding the psychological implications for operational proficiency with the integration of multiple displayed viewpoints is critical. The current empirical study addresses this issue in an experimental simulation of an urban search and rescue (USAR) operation. Using miniature vehicles in a simulated environment, participants were tasked with searching through difficult terrain to photograph specific targets. In the experiment, the number of UGVs used and the use of an uninhabited air vehicle (UAV) view were manipulated as between participants variables. Results indicate: (1) that the use of two UGVs (in a team mode) is rather inefficient, (2) that using two UGVs did not meaningfully reduce faults, and (3) that the use of a UAV view, and to a lesser extent two UGVs, improved target localization.
Defining the Challenges Operators Face When Controlling Multiple Unmanned Vehicles BIBAFull-Text 392-396
  Peter N. Squire; Raja Parasuraman
To achieve effective human-robot interaction (HRI) it is important to determine what types of supervisory control interfaces lead to optimal human-robot teaming. Research in HRI has demonstrated that operators controlling fewer robots against opponents of equal strength face greater challenges when control is restricted to only automation. Using human-in-the-loop evaluations of delegation-type interfaces, the present study examined the challenges and outcomes of a single operator supervising (1) more or less robots than a simulated adversary, with either a (2) flexible or restricted control interface. Testing was conducted with 12 paid participants using the RoboFlag simulation environment. Results from this experiment support past findings of execution timing deficiencies related to automation brittleness, and present new findings that indicate that successful teaming between a single human operator and a robotic team is affected by the number of robots and the type of interface.
A Visualization Framework for Bounding Physical Activities Towards a Quantification of Gibsonian-Based Fields BIBAFull-Text 397-401
  Jeonghwan Jin; Ling Rothrock
In a human-robot communications problem in which a mobile robot and an astronaut are required to work together to maintain network communication, it is possible for the mobile robot and the astronaut to have multiple courses of actions to restore communications if it becomes disrupted. To effectively accomplish a team's mission, a human supervisor responsible for monitoring and supervising the terrestrial activities of mobile robots and astronauts in this domain needs useful decision aiding tools in order to identify productive courses of action. Motivated by this, we propose a visualization framework based on Gibsonian-based fields for representing a mobile robot and an astronaut's possible action strategies to maintain their network communication in a continuous and dynamic environment and for graphically representing bounds on actualized action strategies of the robot and the astronaut based on their possible action strategies. The authors submit that it is not sufficient simply to calculate all the possible actions of the mobile robot and the astronaut. It is equally important to provide interfaces that reveal affordances in the domain in a manner that delineates the length and breadth of action opportunities and human perceptual and physical capabilities. We present a simple conceptualization of the problem of robot-astronaut communication in order to develop a framework for analysis that can be generalized to multiple robots and astronauts communicating to meet multiple objectives.
Effective Human to Human Communication of Information Provided by an Unmanned Vehicle BIBAFull-Text 402-406
  Patricia L. McDermott; Jason Luck; Laurel Allender; Alia Fisher
Much of the research on unmanned-vehicles (UVs) focuses on technology or interface design. This study however, investigated how to best support effective communication between the operator monitoring a UV and the Soldier in the field using that information to complete a mission. Several questions arise: Does the operator need to be co-located with Soldiers in the field or can he or she be in a more secure rearward location? Does the team need the capability to transmit visual images or is radio communication adequate? Is information from one type of UV better than others? Do real time mapping and tracking technologies increase situation awareness (SA)? To begin to answer these questions, military teams conducted rescue missions using the video game Raven Shield as a simulated battlefield. The analysis of performance data, self reports, and observations provide some valuable insight to these questions.
Situation Awareness in HRI with Collaborating Remotely Piloted Vehicles BIBAFull-Text 407-411
  Jennifer M. Riley; Mica R. Endsley
In future Army operations, soldiers may be required to remotely operate multiple robotic vehicles and participate in collaborative tasks with these systems. The ability to acquire and maintain situation awareness in tasking and controlling robots will be critical to human-robot interaction. Understanding the critical information requirements for robotics tasks will be important, particularly when operators must work with multiple systems across aerial and ground platforms, and must perform under what will likely be varying levels of system autonomy. Here, we examine SA needs in the context of a collaborative military task involving deployment of a single UAV that is coordinating with multiple UGVs to identify "safe lanes" for advancing troops. Cognitive task analysis was conducted for the task, along with an examination of potential function allocations that may require operator multi-tasking and frequent task switching. Issues in developing and maintaining situation awareness are discussed.

COGNITIVE ENGINEERING AND DECISION MAKING: Ecological Interface Design, and Decision Biases and Styles

Visual Sensitivity of Dynamic Graphical Objects BIBAFull-Text 412-416
  Munira Jessa; Catherine M. Burns
Advanced display design, such as Ecological Interface Design (EID), makes extensive use of complex graphical objects. Research has shown that by following EID methodologies, operators have better performance with the EID displays (Pawlak and Vicente, 1996). However, past research does not consider visual aspects of the graphical objects used in EID. Of particular interest is how different design decisions of graphical objects affect the performance of the objects used within that design. We examined the visual sensitivity of dynamic graphical objects, examining which features make certain graphical objects visually superior for certain tasks. It was found that for simple dynamic objects, a line changing in angle was the most noticeable emergent feature. For complex graphical objects, those that mimic a "bull's eye" should be used for target-indicator displays, "solid objects" should be used for comparison meters, and changes in shape sizes should be used in trend meters. These findings provide guidance for designers of dynamic advanced graphical displays.
Sensor Noise and Ecological Interface Design: Effects of Increasing Noise Magnitude on Operators Performance BIBAFull-Text 417-421
  Olivier St-Cyr; Kim J. Vicente
We studied the impact of sensor noise on operators' performance using a display based on the Ecological Interface Design (EID) framework with a representative thermal-hydraulic process simulation. A previous study conducted by St-Cyr and Vicente (2004) showed no difference between EID and non-EID interfaces when the magnitude of sensor noise was randomly increased. In this paper, we describe a study that was designed to investigate the impact of gradually increasing the magnitude of sensor noise on EID versus non-EID interfaces. We hypothesized that as the magnitude of sensor noise increase, performance would worsen for both EID and non-EID participants. Our results suggest that increasing the magnitude of sensor noise does compromise both EID and non-EID interfaces. However, the EID group experienced a significantly larger decrease in performance. This may be explained by the fact that participants in the EID group had to deal with distorted emergent features.
An Empirical Study of Calibration in Air Traffic Control Expert Judgment BIBAFull-Text 422-426
  Ashley Nunes; Alex Kirlik
In contrast to many studies revealing biases in the probabilistic judgments of task-naïve participants, a growing body of literature has revealed that over time, professionals are able to gain a reasonably accurate appreciation for the inherent uncertainty that exists in their work environments. The present study assessed how well experienced (working) air traffic controllers are able to predict the probability of the loss of separation between a pair of converging aircraft. Sixteen controllers expressed probabilistically whether or not the depicted pair of aircraft would lose separation. The actual probability of conflict was manipulated by varying the time differential between when each pair of aircraft would reach the point of potential conflict, coupled with uncertainty due to wind perturbations. Results revealed that in instances where perceptual information was available to distinguish between conflicts and non-conflicts, the difference between the actual conflict probability and the mean of the controllers' judged probabilities of conflict was minimal, highlighting the high calibration level of these domain experts at an aggregate level.
Judgments under Uncertainty and Time Pressure: Modeling and Analysis of Operators Judgments of Customers Creditworthiness BIBAFull-Text 427-431
  Younho Seong
Judgments about uncertain environments have been studied extensively in a variety of settings. The judgments of operators regarding customers' creditworthiness when they wish to purchase items that extend their credit lines over their limits are of particular interest. The lens model and its extension provide a frame work to identify an environmental state based on relevant cues. An analysis of the performance of operators' judgments in a financial institution by use of the lens method is presented in this paper. The results of the analysis show that there are differences in the judgment policies of operators in many areas including the methods for using information, the consistency in implementing judgment policies, among other. These differences are very critical elements in an institution's relationship with its customers. Finally, an on-going experiment to support and train operators in the making of consistent and valid judgments by the use of cognitive feedback is discussed.
Relating Decision Making Styles to Predicting Self-Efficacy and a Generalized Expectation of Success and Failure BIBAFull-Text 432-436
  Thomas E. Nygren; Rebecca J. White
The theoretical and applied distinction between a propensity toward a more intuitive decision style versus a more analytical style has gained prominence in recent years. A self-report measure, the Decision Making Styles Inventory, is presented and is shown to differentiate among those who endorse an analytical, an intuitive, or an avoidant, regret-based decision style. Results from one study, a horse race betting task, indicated that those who endorsed a decision style, particularly those endorsing a flexible analytical and intuitive style, performed better on the task than those who did not. A second study clearly showed that decision style was related to self reports of self-efficacy, optimism, and self-regard. These results suggest that having either an analytical, intuitive or combined decision style is beneficial to the decision maker.

COGNITIVE ENGINEERING AND DECISION MAKING: Human-Robot Interaction: From Fieldwork to Simulation to Design

Up from the Rubble: Lessons Learned about HRI from Search and Rescue BIBAFull-Text 437-441
  Robin R. Murphy; Jennifer L. Burke
The Center for Robot-Assisted Search and Rescue has collected data at three responses (World Trade Center, Hurricane Charley, and the La Conchita mudslide) and nine high fidelity field exercises. Our results can be distilled into four lessons. First, building situation awareness, not autonomous navigation, is the major bottleneck in robot autonomy. Most of the robotics literature assumes a single operator single robot (SOSR), while our work shows that two operators working together are nine times more likely to find a victim. Second, human-robot interaction should not be thought of how to control the robot but rather how a team of experts can exploit the robot as an active information source. The third lesson is that team members use shared visual information to build shared mental models and facilitate team coordination. This suggests that high bandwidth, reliable communications will be necessary for effective teamwork. Fourth, victims and rescuers in close proximity to the robots respond to the robot socially. We conclude with observations about the general challenges in human-robot interaction.
Overcoming the Keyhole in Human-Robot Coordination: Simulation and Evaluation BIBAFull-Text 442-446
  Martin Voshell; David D. Woods; Flip Phillips
When environment access is mediated through robotic sensors, field experience and naturalistic studies show robot handlers have difficulties comprehending remote environments -- they experience what domain practitioners often call a 'soda straw'. This illustrates the keyhole effect in Human Robot Interaction, a CSE phenomena studied in the context of large virtual data space interfaces and the current research seeks to reduce this effect. A simulation for human-robot coordinated search and rescue was created based on WTC response experiences. Pilot studies showed traditional performance measures to be inadequate in analyzing control and exploration tasks therefore a novel analysis approach based on fractal path tortuosity was developed. New interface concepts for helping remote observers perceive environmental affordances were then tested using the simulation environment and evaluation measures. These studies look to concepts based on Gibsonian principles to reduce keyhole effects in control interfaces to enhance remote functional presence in Human-Robot Coordination.
Human-Robot Interaction Design: Understanding User Needs and Requirements BIBAFull-Text 447-451
  Julie A. Adams
Goal-Directed Task Analysis is being applied to assessing the needs and requirements for developing novel techniques and tools to permit a small number of humans to supervise large robotic teams. The paper presents a preliminary overall goal hierarchy as well as a preliminary communication goal hierarchy based upon the initial analysis. This research involves working directly with the Nashville Metro Police department's Bomb Squad and the Nashville Metro Fire Department's HAZMAT team. The focus is the assessment of actual user needs and requirements employing well-defined user centered design practices in combination with Goal-Directed Task Analysis. The resulting Goal-Decision-SA structure will be employed to develop potential human-robot interaction designs for further qualitative and qualitative evaluation. The objective is to successfully integrate robots into the Chemical, Biological, Radiological, Nuclear and Explosive device search and rescue tasks such that the robots complement and augment the current human capabilities.
Functional Requirements for Effective Decision Making in Human-Robot Teams: Lessons Learned from Operational Settings BIBAFull-Text 452-456
  James Tittle; William Elm; Scott Potter
Many environments require humans and robots operating together to accomplish complex and dangerous tasks, but technology-centered designs often support robot navigation but not the mission goals of the organization using the robot. Urban Search and Rescue (USAR) is a particularly valuable domain to identify general functional requirements for effective HRI, and our purpose in this paper is to demonstrate how a CSE approach can lead to valuable design guidelines that more effectively support decision making within Human-Robot teams. Our analysis of HRI in USAR lead us to identify several important guidelines for supporting effective coordination for Human-Robot teams: including (i) enable individual problem holders to have direct control over point-of-view to facilitate active information seeking, and (ii) create common reference frames on shared imagery so different problem holders can remotely coordinate information and actions. Designs based on these guidelines will support a broad class of coordinated activities between team members.
Validating USA Rsim for use in HRI Research BIBAFull-Text 457-461
  Jijun Wang; Michael Lewis; Stephen Hughes; Mary Koes; Stefano Carpin
HRI is an excellent candidate for simulator based research because of the relative simplicity of the systems being modeled, the behavioral fidelity possible with current physics engines and the capability of modern graphics cards to approximate camera video. In this paper we briefly introduce the USARsim simulation and discuss efforts to validate its behavior for use in Human Robot Interaction (HRI) research.

COGNITIVE ENGINEERING AND DECISION MAKING: Interruptions, Distractions, and Attention Management: A Multifaceted Problem for Human Factors

Symposium Overview BIBAFull-Text 462
  Mark John
Interruptions and distractions are a serious problem for many tasks, from programming a device to forming a battle plan, and from driving a car to monitoring airspaces. Interruptions and distractions can interfere with short term memory in planning and executing plans, and they can divert attention and reduce processing capacities for the detection and interpretation of significant events in dynamic situations. Attention management across tasks, and even within complex tasks, is a multi-faceted cognitive, perceptual, and social problem for users and display designers alike. The key to improving attention management is understanding the human, task, and environment issues and designing technologies that dovetail with and exploit that understanding. The research presentations in this session delve into several different facets of attention management and interruption. They analyze the issues, develop design principles, and evaluate alternative interface designs.
Auditory Preemption versus Multiple Resources: Who Wins in Interruption Management BIBAFull-Text 463-467
  Christopher D. Wickens; Stephen R. Dixon; Bobbie Seppelt
We examined the effects of modality (auditory versus visual) and spatial separation when a simulated vehicle control (tracking) task (the ongoing task: OT) was time shared with a digit entry task (the interrupting task: IT), contrasting the predictions of auditory preemption theory with that of multiple resource theory. Participants performed the tracking task with auditory display of the phone numbers, or with visual display at eccentricities ranging from 0 deg (overlay) to 45 deg. Auditory input improved IT performance relative to visual, but disrupted OT performance, thereby supporting the role of auditory preemption. This cost did not grow with longer messages. In contrast, at eccentricities above 15 deg, auditory superiority emerged for both tasks, highlighting the role of multiple resources, and separation produced greater costs to the OT than to the IT. Therefore, both discrete tasks, and auditory delivery have inherent preemptive effects on the continuous visual OT. The results are also interpreted in the context of the non-linear costs to dual task performance with increasing separation from the eye-field to the head-field, and the support for different visual hemi-fields for concurrent processing of verbal and ambient spatial information.
Huh, what was I doing How people use environmental cues after an interruption BIBAFull-Text 468-472
  J. Gregory Trafton; Erik M. Altmann; Derek P. Brock
We examine the effect of environmental cues on being interrupted while performing a task. We conducted an experiment in which participants, after an interruption, received either a blatant environmental cue of their previous action (a red arrow), a subtle environmental cue of their previous action (a cursor that was placed in the same location as their previous action), or no environmental cue at all. We found that participants in the blatant condition resumed their task faster than participants in the other two conditions. Furthermore, a subtle environmental cue was no better than no cue at all. The results support our model of memory for goals.
Recovery from Interruptions to a Dynamic Monitoring Task: The Beguiling Utility of Instant Replay BIBAFull-Text 473-477
  Mark John; Harvey S. Smallman; Daniel I. Manes
Detecting changes in complex monitoring tasks is important for situation awareness, yet surprisingly difficult. Interruptions exacerbate this problem. An intuitively appealing solution to this problem is Instant Replay. Users could replay interrupted periods at high speed to quickly perceive changes. Instant Replay's appeal seems to rest on its familiarity and realistic re-presentation of the temporal sequence of the interrupted situation. However, current theories of perception, including Naïve Realism (Smallman & St. John, 2005), predict this emphasis on realism to be misguided. We compared two versions of replay against three alternative tools in a naval air warfare simulation in which 35 participants monitored a busy airspace for significant changes. One alternative, CHEX, a situation awareness recovery concept we are developing, automatically detects and logs changes into an interactive table. CHEX provided an effective representation for quickly recovering situation awareness. In contrast, realistic Instant Replay proved worse than no support at all.
Graded and Multimodal Interruption Cueing in Support of Preattentive Reference and Attention Management BIBAFull-Text 478-481
  Nadine B. Sarter
A decade ago, attention management was considered by some "the least explored frontier in cognitive science and human-machine cooperation" (Woods et al., 1994). Today, at least one aspect of attention management -- interruption handling -- still poses a major challenge for the design of human-machine systems and computer-supported collaborative work. Successful interruption management requires that both unintentional dismissals and preemptive integrations of interruption signals are avoided (Latorella, 1999). One means of achieving this goal is to support preattentive reference, i.e., the processing of interruption signals that occurs before attentional selection. Operators need to be provided with at least partial information about the nature and cognitive requirements of a potential interruption, and this information should be presented in a way that allows for peripheral access. This paper will discuss and illustrate how currently underutilized graded and multimodal information presentation could help accomplish this goal and support various stages of the overall interruption management process.

COGNITIVE ENGINEERING AND DECISION MAKING: Trust in Automation and Information Presentation

Effects of Attribute and Goal Framing on Automation Reliance and Compliance BIBAFull-Text 482-486
  Frank C. Lacson; Douglas A. Wiegmann; Poornima Madhavan
Presentation of an aid's reliability may have mixed results on utilization due to differences in the way the reliability is framed, as well as its effects on reliance versus compliance. Using an aided signal detection task, the current study compared effects of attribute framing (80% correct versus 20% incorrect) and goal framing (focusing on hits and correct rejections versus misses and false alarms) on sensitivity, response bias, compliance, and reliance. Sensitivity and response bias results indicated few differences between aided groups. Information framing did lead to differences in compliance, but not reliance compared to an unframed group. However, reliance differences occurred when comparing positive and negative framing group. These results indicate that the manner in which information about the reliability of a diagnostic aid is presented can have significant, albeit subtle, effects on automation utilization.
Effects of Information Source, Pedigree, and Reliability on Operators Utilization of Diagnostic Advice BIBAFull-Text 487-491
  Poornima Madhavan; Douglas A. Wiegmann
Studies have demonstrated that humans appear to apply norms of human-human interaction to their interaction with machines. Yet, there exist subtle differences in peoples' perceptions of automated aids compared to humans. We examined factors differentiating human-human and human-automation interaction, wherein participants (n = 180) performed a luggage-screening task with the assistance of human or automated advisers that differed in pedigree (expert vs. novice) and reliability (high vs. low). Dependence on advice was assessed. Participants agreed more with an automated 'novice' than a human 'novice' suggesting a bias toward automation. Automation biases broke down when automated aids portrayed as 'experts' generated errors, leading to a drop in compliance and reliance on automation relative to humans. The results have implications for the development of theoretical and computational models of optimal user dependence on decision aids.
Effects of Automation Failure in a Luggage Screening Task: A Comparison between Direct and Indirect Cueing BIBAFull-Text 492-496
  Juliana Goh; Douglas A. Wiegmann; Poornima Madhavan
The present study investigated the use of two automated aids of different reliabilities in a luggage screening task. A Direct Cue consisting of a green circle around a potential target directs attention to a specific part of the luggage image, while an Indirect Cue, consisting of a green border around an image determined to have a target, does not. Direct Cues offer an advantage in visual inspection tasks because they guide attention to specific areas of the visual image but this can also cause attentional tunneling. Furthermore, the reliance on automation may negatively impact manual performance after the aid is removed or is no longer available. Thus, two issues were investigated in the current study: (1) how do failures in Direct and Indirect Cues affect reliance and (2) how does a complete failure affect performance after operators had the use of an automated aid? Results suggest that reliance patterns were more optimal with the Direct Cue than with the Indirect Cue and performance with a more reliable Indirect Cue was not much better than a less reliable one. The results also suggest that manual performance, when the aid was removed, was better for participants who had used the automated aids compared to control participants who did not have any use of the aid previously. The advantage of previously aided performance on subsequent manual performance was greatest for those who had used the more reliable Direct Cue. Explanations and implications are discussed.
Validation of a Two Factor Structure for System Trust BIBAFull-Text 497-501
  Jennifer A. Safar; Carl W. Turner
Customers assess a company's ability to meet their needs based upon service interactions with that company. The growth of the Internet as an information transfer medium has dramatically increased reliance on communication between a human and a computer during service interactions. Although trust is known to be an integral part of customer experience during human-to-human interactions, it has been suggested that even when service is provided by an inanimate entity, trust remains a relevant factor. This study evaluated a tool purporting to measure system trust during automated service interactions. Participants completed an auto rate quote via one of two insurers' websites. A two-factor structure was uncovered. The scale exhibited strong internal consistency, sensitivity to objective task success, and was significantly related to several other customer experience measures. The results provide convergent evidence that the scale is a valid and reliable tool for describing customers' experiences during automated interactions.
Too Little or Too Much: The Effect of Feedback on Risk Assessment in a Missile Defense Task BIBAFull-Text 502-506
  Patricia L. McDermott; Michael Barnes; Shaun Hutchins
Operators must often assess risk and take actions in proportion to that risk. This is not an inherently easy task and based on previous experiments, visualization aids may not be the entire solution to aiding operators. This experiment explored the impact of feedback paradigms on performance in a national missile defense (NMD) task. Participants had extensive practice with one of three types of feedback styles: averaged results after a set of scenarios, constant feedback after every scenario, or constant feedback with forced reflection. This study has three main contributions to decision-making research. 1) Although the trust in automation literature shows that averaged feedback increases understanding of the relative frequency of errors, this NMD task showed that constant feedback is more effective than averaged feedback. 2) Participant performance was still improving after three sessions, suggesting the need for more intense training. 3) NMD provides a concrete domain with viable metrics for investigating the perception of risk and uncertainty.

COGNITIVE ENGINEERING AND DECISION MAKING: Emergency, Crisis Management, and Knowledge Elicitation

A Sociotechnical Systems Analysis of the Toronto Sars Outbreak BIBAFull-Text 507-511
  Andrea Cassano Piche; Kim J. Vicente
In February 2003, an outbreak of Severe Acute Respiratory Syndrome (SARS) in Toronto, Canada, resulted in 438 probable SARS cases, 44 deaths, and over 25,000 individuals quarantined. The purpose of this study was to investigate whether or not the predictions of Rasmussen's (1997) framework for risk management can explain how and why SARS was transmitted in Toronto. There are two propositions for this case study. First, multiple actions, decisions, and degrees of capability at all levels of the system are needed to explain how SARS was transmitted. Second, a lack of vertical integration between individuals and organizations explains why SARS was widely transmitted. Both propositions of this case study are supported by the data in the National Advisory Committee's report (Health Canada, 2003). Furthermore, almost all of the predictions made by Rasmussen's (1997) framework were confirmed by the events that transpired during SARS.
Collaborative Cross-Checking to Enhance Resilience BIBAFull-Text 512-516
  Emily S. Patterson; David D. Woods; Richard I. Cook; Marta L. Render
There has been a longstanding consensus that supporting error detection and recovery processes is critical for very high safety levels because it increases system resilience. System resilience is defined in Resilience Engineering as successful adaptation to variations, changes, and surprises by organizations, groups, or individuals. Cross-checking is a critical component of resilience because it can enable detection of erroneous assessments or actions while negative consequences can be mitigated or eliminated. Prior studies suggest that cross-checking where an additional human with a fresh perspective breaks fixations may be an effective strategy. Nevertheless, collaborative cross-checking remains a somewhat murky concept. In this paper, we describe in detail three healthcare incidents where collaborative cross-checking played a key role. Emerging patterns that provide opportunities for follow-on research are discussed.
Supporting Decision Making by a Critical Thinking Tool BIBAFull-Text 517-521
  Kees van Dongen; Jan Maarten Schraagen; Aletta Eikelboom; Guido te Brake
Building up situation understanding is one of the most difficult tasks in the beginning stages of large-scale accidents. As ambiguous information about the events becomes available, decision-makers are often tempted to quickly develop a particular story to explain the observed events. As the accident evolves, decision-makers can fail to revise their initial assessments despite contradicting information. Our approach is to reduce fixation errors and confirmation bias by providing critical thinking support. In a laboratory experiment with 60 participants, we compared the effect on decision making of a critical thinking tool, which requires the explication of evidence-conclusion relations in situation assessment, with two control conditions. Participants acted as crisis managers determining the likely cause of accidents. The results show a positive impact of the tool on both the decision-making process and decision making effectiveness. Participants did, however, take more time to arrive at a conclusion using the tool.
Expanding Team Knowledge Elicitation through Procedural, Temporal, and Strategic Elements BIBFull-Text 522-526
  Issac Brewer; Michael D. McNeese; Tim G. Frazier; Sven Fuhrmann; Ivanna S. Terrell


Large Scale Coordination: The Study of Groups at Work BIBAFull-Text 527-528
  Christopher P. Nemeth
Naturalistic decision making (NDM) methods have previously been applied to understand individual and group cognition. The systemic aspects of work that are unavailable through the study of individuals or a single group can be revealed by cognitive research at large scale, among and across groups. The papers in this symposium explore the use of NDM methods including cognitive systems engineering to reveal how groups of operators have developed ways to perform inter-group work in real world settings. Insights from such studies inform the development of system-level products, including safety counter-measures and information and communication technology (ITC) that is intended to support this work.
Fostering Shared Situation Awareness and On-Track Safety Across Distributed Teams in Railroad Operations BIBAFull-Text 529-533
  Emilie M. Roth; Jordan Multer
Cooperative strategies of individuals within a distributed organizational structure can contribute to increased efficiency of operations and safety. We describe selected results of a cognitive task analysis that examined the cognitive and collaborative demands and activities of railroad roadway workers. The findings highlight the informal cooperative strategies that railroad workers have developed across distributed teams consisting of roadway workers, train crews, and railroad dispatchers that foster shared situation awareness and enhance on-track safety. We discuss design implications for leveraging new digital technologies and location finding systems to more effectively support these informal strategies to improve efficiency and enhance on-track safety are discussed.
Large-Scale Coordination in Emergency Response BIBAFull-Text 534-538
  Laura G. Militello; Laurie Quill; Emily S. Patterson; Robert Wears; Jill A. Ritter
Coordination is a key element in emergency response. This paper focuses on coordination as it occurred in a county-level Emergency Operations Center (EOC) during a simulated tornado. The EOC is responsible for locating, purchasing, and transporting resources to the disaster scene(s). The EOC is an ad hoc team made up of government agencies, private companies (i.e., hospitals, utilities, etc.), and non-governmental agencies. These decision makers come together to engage in creative problem solving in order to solve often complex logistics and coordination problems generally under intense time pressure during a rapidly evolving situation. Lessons learned from this exercise highlight coordination challenges including asymmetric information flow, natural fault lines, roles and functions, co-location benefits, emergent leadership, fragmented situation awareness, information displays, room design, and quick reference tools.
Negotiation and Coordination: A Preliminary Field Study of Conflict Management in Large Scale Collaboration BIBAFull-Text 539-543
  Yan Xiao; Cheryl Plasters; F. Jacob Seagull; Colin Mackenzie; Marina Kobayashi; Susan Fussell; Sara Kiesler
Coordination of activities in many settings can be characterized by management of conflicts, potential and actual, because of resource limitations, high-stakes consequences, uncertainty, goal conflicts among stakeholders and hetero-hierarchical organizational structures. To understand coordination in such systems, we conducted a field study of management of surgical operating rooms. Although coordination efforts were focused on resolution of interdependencies, such as progress monitoring, scheduling and rescheduling, and prodding, coordinators managed a set of complicated conflicts, often through opportunistic means. They were very sensitive to potential conflicts, and used many different means to resolve the conflicts as reported in the literature. Additionally, they were very concerned with perceived fairness. The findings have direct implications to the deployment of information technology as it will change accuracy of information, barriers to access and means of information dissemination.
Challenges to Remote Emergency Decision-Making for Disasters or Homeland Security BIBAFull-Text 544-547
  Colin Mackenzie; Peter Fu-Ming Hu; Carsten Fausboll; Michael Nerlich; Thomas Benner; David Gagliano; Warren Whitlock; David Lam; Yan Xiao
New technology allows information gathering and collaboration across information networks that would be of benefit to emergency response. In a Homeland Security Exercise we compared the utility of fixed and mobile video and high quality still images on remote expert decision making. Sixteen experts situated in 3 countries viewed and evaluated events of the exercise assisted by audio commentary of local knowledge experts. They evaluated the usefulness of black and white (B/W) compared to color images, fixed fast video versus slow video and still images. Technical difficulties interrupted image transmission to one remote site for half the Exercise. However, the images were found useful, color more than B/W, mobile more than fixed. The combination of still images and video was best. Playback of recorded images was especially useful for remote evaluation and decision making. Improved reliability for these imaging technologies could improve shared awareness and remote distributed team collaboration for Homeland Security events.


A Comparison of Observer and Incumbent Ratings of Situation Awareness BIBAFull-Text 548-552
  Michael D. Matthews; Silas G. Martinez; Jarle Eid; Bjorn Helge Johnsen; Ole Christian Boe
The Situation Awareness Behavioral Rating Scale (SABARS) utilizes ratings by expert observer/controllers (O/Cs) to evaluate situation awareness (SA) of infantry small unit leaders. Previous research (Matthews et al., 2004) showed SABARS to be predictive of a variety of performance measures. The current study explored the question of whether small unit leaders could use SABARS to accurately rate their own behavior as an index of their SA. To evaluate this question, 12 Norwegian Army and Navy Academy cadets participating in the role of squad leader during summer training exercises were given the SABARS to complete following an infantry mission. An experienced officer O/C observed the cadets though the execution of the mission and also provided SABARS ratings on the squad leader. Results indicated that "self-SABARS" evaluations did not correlate with SABARS completed by O/C's, and were not predictive of performance criteria. O/C-completed SABARS were, however, predictive of performance criteria thus replicating findings reported previously (Matthews et al., 2004). Implications for assessing SA in the field are discussed.
Determining the Information Needs of Puget Sound Boaters BIBAFull-Text 553-557
  David W. Jones; Janet I. Olsonbaker
Puget Sound is known for its highly variable weather and ocean currents. Trip planning for this challenging environment is critical for boating safety. We conducted a survey of the Puget Sound boating community to determine their information needs. We used a web-based questionnaire supplemented with face-to-face surveys. We received 610 responses. The respondents represented a wide range of the boating community. The boaters' most important environmental need was for daily weather forecasts and their most desired forecast parameters were wind speed, currents, and wave height. Respondents also commented on their frustration with accessing the needed information. Analysis of this survey and guidance from an advisory panel are being used to develop a user-centered designed (UCD) web portal, the Boater Information System (BIS) that will attempt to improve the situation awareness (SA) for a diverse user group.
Take the Advice of a Decision Aid: I'D Rather Be Wrong BIBAFull-Text 558-562
  Hall P. Beck; Mary T. Dzindolet; Linda G. Pierce
It has been proposed that operators sometimes refuse to follow the guidance of a decision aid that they know is offering correct or useful advice (intent errors). To test this premise, some participants received a "recommendation" from a computerized decision aid before each of 100 target detection trials. These operators were told that the aid always offered correct advice. A control group performed the same task without the decision aid. Most of the aided participants (82%) made one or more errors because they were unwilling to follow the aid's recommendations. Furthermore, the number of errors made by the experimental and control groups was not statistically different. Extrapolation of the results suggests that efforts to reduce automation disuse should include training designed to mitigate intent as well as appraisal errors.
Using a Linguistic Analysis Tool to Detect Deception BIBAFull-Text 563-567
  Mary T. Dzindolet; Linda G. Pierce
Detecting deception is important, yet accuracy rates remain low (e.g., DePaulo & Friedman, 1998). Pennebaker et al. (2003) suggest a linguistic analysis tool may be able to detect deception because people use a different linguistic style when telling the truth than when lying. For example, the anxiety experienced by liars may "leak" into their words. The cognitive resources devoted to the lie will be taken from the message. Newman et al. (2003) found support for these hypotheses using the Linguistic Inquiry Word Count (LIWC). Dzindolet and Pierce (2004a) found the LIWC was useful in detecting deception among participants discussing music preferences. This study expands their work to include other topics. Results from the 2 (topic: movie or television) x 2 (topic importance: high or low) x 2 (communication type: lie or truth) design indicated that linguistic analysis tools may be useful in detecting deception across a variety of topics.
When to Act Managing Time-Accuracy Trade-Offs in a Dynamic Belief Updating Task BIBAFull-Text 568-572
  Michael Hildebrandt; Joachim Meyer
Diagnostic decisions in dynamic environments often require trade-offs between decision accuracy and timeliness. The longer a diagnostic decision is postponed, the more the accuracy of the decision may increase, while at the same time the probability of successfully executing remedial actions decreases. Kerstholt (1994) reports that in a task where a continuous process had to be monitored, subjects' reliance on a judgment-oriented strategy (requesting additional information before making a decision) frequently led to late decisions. In this study, we were interested if similar effects appear when the motivation to postpone the decision was induced by the prospect of an alarm appearing later in the trial. A normative model based on Bayesian belief updating was constructed to determine optimal strategies under the conditions of the independent variables alarm timing (early, late) and alarm reliability (0.7, 0.9). Results are in partial agreement with earlier studies by showing evidence of a judgment-oriented strategy in the low-reliability condition. However, in the high-reliability condition, a high proportion of early decision errors, consistent with an action-oriented strategy favoring decision timeliness over accuracy, occurred.
Evaluation of Human Performance in a Supervisory Inspection Task Monitoring Multiple Hybrid Inspection Systems BIBAFull-Text 573-577
  Sandhya Kommidi; Pallavi Dharwada; Anand K. Gramopadhye; Byung R. Cho; Lawrence Grimes
The demand for consistent quality has led to 100% inspection using automated systems rather than the traditional sampling with human inspectors. However, these automated systems cannot adapt to novel situations to meet the required performance without human intervention. The need for cost-effective and superior inspection performance has resulted in hybrid systems in which the functions are allocated depending on the capabilities of humans and machines. With the increasing availability of computer technology due to decreased costs and size, the role of humans in inspection systems is changing from that of a continuous "online" inspector to that of a supervisor of multiple tasks. This study uses a computer-based visual inspection simulator to investigate the role of the human as a supervisor in inspection systems, with the main focus on the effect of performance of one hybrid inspection system on human decision to intervene in another system to optimize the inspection performance.
Searching for Cues: An Analysis on Factors Effecting the Decision Making Process of Regional Airline Pilots BIBAFull-Text 578-581
  Yee-Len Khoo; Kathleen Mosier
Research on aviation accidents and incidents has indicated humans are potentially the "weak link" in the chain of accident causation. The problem faced by researchers here is there is often no clear standard of determining what decision is "correct" or "incorrect". In addition, the loose coupling of an event outcome and the decision process makes it hard researchers to use accident reports as a reliable indicator of the quality of the decision. The goal of this research is to explore cognitive processes of pilots when dealing with the types of decisions required under time pressure and with conflicting information and how pilots use information as they are performing diagnostic and decision-making tasks in the automated cockpit. Differences were found between pilots with more experience in automated aircrafts however predicted automation bias effects were non-apparent.
The Continued Evolution of Team Research: A Theoretical Model of Performance in Multiteam Systems BIBAFull-Text 582-585
  Joseph W. Guthrie; Heather A. Priest; Eduardo Salas
The growth of global companies and partnerships in and across organizations and the growth of coalitions in military campaigns have brought about new needs in team research. Specifically, organizations and the military alike are beginning to utilize teams of teams or multiteam systems (MTS) to complete more complex tasks. A MTS has been defined as "two or more teams that interface directly and interdependently in response to environmental contingencies toward the accomplishment of collective goals" (Mathieu, Marks, & Zaccaro, 2001, p. 290). We believe that MTS represent the next evolution of team research. Because of the growing importance and of MTS to the military and organizations this paper introduces a theoretical model of MTS performance, the Joint Operations Effectiveness Model. We provide a brief synopsis of teams and findings from previous team research before presenting a more detailed description of the proposed model.
Predicting Group Decision-Making with a Computerized Text Analysis Tool BIBAFull-Text 586-590
  Mary T. Dzindolet; Arleta Stover; Linda G. Pierce
Decision-making tasks are often performed in groups because it is believed that a discussion of the topic from varying individual perspectives will lead to a better decision. However, researchers find group members often spend the majority of their discussion time focused on information members have in common rather than on unique pieces of information each group member holds (Stasser & Titus, 2003). Determining which groups are most likely to fall into this trap would benefit team leaders. A computerized text program, the Linguistic Inquiry Word Count (LIWC), offers one technological tool to meet this need. Significant correlations between LIWC word categories and time groups spent discussing common information, discussing unique information, and making the decision were found among 104 students who assessed candidates for student government president in face-to-face groups of two or four. The linguistic profile of groups following this unproductive pattern is identified and suggestions for further research are discussed.
The Neocities Simulation: Understanding the Design and Experimental Methodology used to Develop a Team Emergency Management Simulation BIBAFull-Text 591-594
  Michael D. McNeese; Priya Bains; Isaac Brewer; Cliff Brown; Erik S. Connors; Tyrone Jefferson; Rashaad E. T. Jones; Ivanna Terrell
This paper describes the continued development of a scaled-world simulation designed to conduct empirical research on team cognition and decision-making within a distributed environment. The NeoCITIES simulation was created to study decision-making and the impact of hidden knowledge profiles on team performance within a distributed command, control, and communications (C3) setting. NeoCITIES has been designed for the purpose of representing both new and operationally relevant scaled worlds, while emulating the complexities and attributes of emergent decision-making scenarios involving emergent counterterrorism events. Because patterns of activity emerge across time, knowledge is often hidden and disconnected within and across teams. NeoCITIES has been orchestrated to assess and evaluate the extent to which teams can socially construct knowledge while ineteracting through various means of technological support. Specifically, NeoCITIES is an interactive computer program designed to display information pertaining to events and occurrences in a virtual city space. The teams in the simulation represent three separate services (e.g., Police, Fire/EMS, and Hazmat) in which they must assess situations, interact and communicate according to their inter-team and intra-team roles, allocate resources in a timely manner, and make decisions within the context of emergency crisis management. Once NeoCITIES development has been completed, the simulation will be used as an experimental task to measure the impact of hidden knowledge profiles on teamwork and decision-making in the distributed team context.
When Function follows Form: Anthropomorphism of Artifact Faces BIBAFull-Text 595-597
  Valerie K. Sims; Matthew G. Chin; Ryan E. Yordon; David J. Sushil; Daniel J. Barber; Clint W. Owens; Hana S. Smith; Michael J. Dolezal; Randall Shumaker; Neal Finkelstein
Participants rated machine "faces" which varied in terms of eye size, eye shape, distance between eyes, and relationship to background color (white on black or black on white). Ratings were made for aggression, friendliness, intelligence, trustworthiness, and degree of animation. In addition, reaction time was collected for all ratings. Large, round, and close-set eyes were perceived most negatively across ratings. Aggression ratings were predicted by simple variables, whereas trustworthiness ratings were predicted by interactions among variables. Some judgments of form require the assessment of specific features, whereas others rely on a "gestalt" assessment of many features simultaneously. Humans attribute personality characteristics to minimal features, suggesting that form of intelligent artifacts is important in predicting human interactions with that item.
Those A-Maze-Ing Robots: Attributions of Ability are Based on Form, not Behavior BIBAFull-Text 598-601
  Linda Upham Ellis; Valerie K. Sims; Matthew G. Chin; Aaron A. Pepe; Clint W. Owens; Michael J. Dolezal; Randall Shumaker; Neal Finkelstein
Participants were introduced to one of three robots -- a bipedal Robosapien, a treaded vehicle, and a wheeled vehicle. They then used voice commands to guide this entity through a maze from a remote destination. Feedback was given via an arrow that showed the entity either responding to the voice commands or ignoring them. The same feedback was given in all conditions. However, participant ratings of mood and their attributions for the robots' abilities and functions differed. These results suggest that interactions with non-human intelligent entities are largely guided by pre-existing schemas. Additionally, individual differences in perceived control over a caregiving situation were predictive of responses to the robot, further supporting the idea that schemas for certain types of human-human interactions are activated by synthetic agents.
Anthropomorphism of Robotic Forms: A Response to Affordances BIBAFull-Text 602-605
  Valerie K. Sims; Matthew G. Chin; David J. Sushil; Daniel J. Barber; Tatiana Ballion; Bryan R. Clark; Keith A. Garfield; Michael J. Dolezal; Randall Shumaker; Neal Finkelstein
Participants rated robotic forms on three scales: perceived aggression, intelligence, and animation. The robot bodies varied along five dimensions: Types of edges (beveled or squared), method of movement (wheels, legs, spider legs, or treads), number of movement generators (2 or 4), body position (upright or down), and presence of arms (present or absent). Across ratings, movement method and presence of arms were the strongest predictors of participant perceptions. Legs and arms, both human characteristics, were associated with more positive attributions. Minimal affective characteristics, as displayed by the body design, are important in user perceptions of use and ability.

COMMUNICATIONS: Speech Communications with Humans and Computers

Search for an Optimum Vibrator Location for Bone Conduction Communication BIBAFull-Text 606-609
  Maranda McBride; Tomasz Letowski; Phuong Tran
The military is interested in ways to increase soldier effectiveness by improving radio communication. Bone conduction (BC) radio communication is attractive because the lightweight, compact design of BC vibrators offers the ability to receive radio communication without compromising situation awareness. Several companies are attempting to accommodate the needs of the military by creating communication devices incorporating BC technologies. However, the effectiveness of these devices differs in many respects. One factor that affects the detectability of signals received via bone conduction is the location of the vibrator on the skull. The intent of this study was to identify optimum locations for the placement of BC vibrators based on hearing threshold levels of various signals. Eleven signals were transmitted via bone conduction to 11 skull locations of 12 volunteers. Results of the study indicate that the condyle might be the most appropriate location because it resulted in the lowest overall threshold level.
Terminal Radar Approach Control: Measures of Voice Communications System Performance BIBAFull-Text 610-614
  O. Veronika Prinzo
When the National Airspace System migrates from its current ground infrastructure and voice communications system to one that encompasses ground and satellite systems, digital data will be the principal communications medium. As technological advances lead to innovations in communications system development, those emerging systems will be evaluated against existing performance parameters. Baseline parameters were derived from waveform analysis performed on 8000 pilot and controller transmissions acquired from the five busiest TRACON facilities in the USA. The major findings were that communications occur quickly and with minimal silence between successive transmissions. Disruptions to efficient information transfer can result from blocked, stepped-on, and clipped transmission -- which occurred in 1.2% of the sampled transmissions. Even so, when transmissions were completely blocked an audible alarm (spoken word 'blocked' or heterodyning) typically alerted the controllers to their presence. Future systems developers may want to exploit and expand this capability to include stepped-on and clipped transmissions.
Simple Visualizations Enhance Speaker Identification When Listening to Spatialized Voices BIBAFull-Text 615-618
  Ryan Kilgore; Mark Chignell
Spatial audio has been demonstrated to enhance performance in a variety of listening tasks. The utility of visually reinforcing spatialized audio with depictions of voice locations in collaborative applications, however, has been questioned. In this experiment, we compared the accuracy, response time, confidence in task performance, and subjective mental workload of 18 participants in a voice-identification task under three different display conditions: 1) traditional mono audio; 2) spatial audio; 3) spatial audio with a visual representation of voice locations. Each format was investigated using four and eight unique stimuli voices. Results showed greater voice-identification accuracy for the spatial-plus-visual format than for the spatial-and mono-only formats, and that visualization benefits increased with voice number. Spatialization was also found to increase confidence in task performance. Response time and mental workload remained unchanged across display conditions. These results indicate visualizations may benefit users of large, unfamiliar audio spaces.
Comparison of Speech With Keyboard and Mouse as the Text Entry Method BIBAFull-Text 619-622
  Sehchang Hah; Vicki Ahlstrom
Federal Aviation Administration (FAA) researchers ran an experiment that compared an automatic speech recognition system with the keyboard and mouse as text input methods. In the speech condition, the participants read the document in its entirety, and the system converted speech into text. They corrected errors using the keyboard and mouse. In the typing condition, the participants corrected errors as they typed. The experimental results showed they spent significantly less time reading than typing to enter the text. When we factored in correction time for both conditions, the results showed that participants took significantly more time in the speech than in the typing condition. Whether they were fast or slow typists, all of the participants preferred typing to speech and performed better in the typing condition than in the speech condition. Optimization of the system and more training may improve the performance of the speech recognition system.
Design Approach for a Customer Care IVRU: Conversational Prompting Style Compared to Directed Dialog BIBAFull-Text 623-627
  T. S. Balaji; Donnelle Weller; Jesse Kates
Interactive Voice Response Units (IVRUs) answer the phones more often than people do in many business domains, including Telecommunication, Personal Finance, Utilities, etc. This paper presents the results of a research study that Sprint initiated to solve a specific business problem within its IVRU. Two design approaches were assessed, pitting a Natural Language with Directed Dialog Fallback structure versus a traditional Directed Dialog framework. Key measurements included task completion and efficiency. The Natural Language with Directed Dialog Fallback design slightly outperformed the Directed Dialog approach by providing a compelling hybrid of two archetypal IVRU approaches.


The Effect of Auditory Progress Bars on Consumer's Estimation of Telephone Wait Time BIBAFull-Text 628-632
  Philip Kortum; S. Camille Peres; Benjamin A. Knott; Robert Bushey
This paper describes the evaluation of four auditory progress bars (APB's) to see if they had the potential to garner high satisfaction scores from users while simultaneously having a positive impact on those callers' perception of hold time during a call to a customer service representative. The APB's varied by sound dimension (pitch/duration change), polarity (increasing/decreasing) and wait time. APB did not impact wait perception significantly for sound dimension or polarity. Analysis of the first call a participant made to the system showed a strong interaction affect, with better performance in the increasing condition for the duration APB, and better performance for the decreasing condition in the pitch APB. However, extremely low customer satisfaction scores for all of the APB's indicated that participants were unhappy with the stimuli. The data provide guidance for the continuing exploration into the proper design of both effective and desirable auditory progress bars.
Privacy Rules: Method and System for Conveying Location-Granularity Preferences with Location-Based Service Requests BIBAFull-Text 633-636
  T. S. Balaji; Robert H. Miller; Clyde C. Heppner; R. Brian Landers
The results of an online survey support a growing body of evidence that user discomfort increases in proportion to the accuracy with which wireless communication networks determine the physical location of a wireless device. We describe a method for conveying and applying user preferences for location granularity (inaccuracy) with such location-based services. Using this method, a user may limit the location granularity either globally, for particular services, or for particular individuals who might wish to locate the user. Upon detecting a request to use a location service, a wireless device sends to the service provider a message directing how to carry out the requested service. Upon receiving the instructions, the service provider would proceed to determine the location of the device, adjust the granularity as appropriate to the user's preference, then return the adjusted location. We believe that this method will alleviate some of users' concerns related to the privacy and control of location information.

COMPUTER SYSTEMS: Keyboards and Text Entry

Pros, Cons, and Changing Behavior: An Application in the Use of the Keyboard to Issue Commands BIBAFull-Text 637-641
  S. Camille Peres; Michael D. Fleetwood; Minmin Yang; Franklin P. Tamborello; Danielle Paige Smith
Despite the fact that keyboard issued commands (KICs) are more efficient than other command methods, experienced users often do not adopt them. In order to examine the factors underlying this phenomenon, a study is presented which investigated the relationships between users' level of knowledge with Microsoft Word, the importance they placed on the costs and benefits of using KICs, and how these factors related to the use of KICs in Microsoft Word. Results indicate that benefits are more strongly associated with the actual use of KICs than costs. The application of these findings to the human factors domain and the implication of the results to facilitate the adoption of efficient techniques and behaviors are discussed.
The Influence of Microsoft's ClearType on Programmer Productivity BIBAFull-Text 642-645
  Randolph G. Bias; James Patrick Williams; Ding-Yu Chung; Samuel A. Burns
An experimental study and a naturalistic field study were conducted to develop detailed behavioral (performance) and affective measures of user responses to ClearType to support the derivation of quantitative estimates of ClearType's impact on user productivity in computer programming tasks.
Effects of a Multitouch Keyboard on Wrist Posture, Typing Performance and Comfort BIBAFull-Text 646-650
  Jennifer Thom-Santelli; Alan Hedge
This study compares the use of a conventional keyboard (CK) and a prototype ultra-low profile MultiTouch keyless keyboard (MTK) that only requires contact force to register a keystroke and allows mousing and gestural input on the same surface. Twelve subjects completed eight randomly assigned 7.5-minute typing tasks of text passages of similar difficulty and identical length for each keyboard condition. Typing speed, accuracy, wrist postures and user comfort were measured. Subjects, typed slower (F1,11 = 41.86, p=0.000) and less accurately (F1,11 = 23.55, p=0.001) on the MTK during the typing tasks. Mean wrist extension was lower for the MTK (F1,11= 10.205, p=0.000) while radial and ulnar deviation did not differ significantly between the two keyboards.. Subjects preferred the CK and reported a higher level of ease (F1,11 = 49.732, p=0.00) and enjoyment (F1,11 = 51.129, p=0.00) during its use. In terms of comfort, subjects reported a higher level of ease and enjoyment in the CK condition. Familiarity and fatigue effects affected the results.
Effects of Chemical Protective Clothing on Task Performance Using Wearable Input Devices BIBAFull-Text 651-655
  Andrea S. Krausman; Maury Nussbaum
Wearable computers allow users the freedom to work in any environment including those that may require protective clothing. Past research has shown that protective clothing impedes performance on manual dexterity tasks. Little information exists, however, regarding how protective clothing affects task performance with wearable input devices. To facilitate future development of wearable input devices, a study was conducted to determine the effects of glove thickness and respirator use on task performance and user preference. Sixteen male participants used both a wearable mouse and touch pad to enter text. Task completion times were 9% slower when participants wore 25-mil versus 7-mil protective gloves, suggesting that thin protective gloves (i.e. 7-mil and 14-mil) are more suitable than thicker gloves when using wearable input devices. Respirator use did not affect task performance. Subjective ratings of difficulty, confidence, and preference provided strong support for the use of a touch pad device rather than a mouse.

COMPUTER SYSTEMS: Input Methods and Display Design

The Effects of Service Availability and Recognition Errors on Trust in Voice User Interfaces BIBAFull-Text 656-660
  Carl W. Turner; Jennifer A. Safar; Mary Hardzinski; Derek Berube
This study was conducted to determine the effects of speech recognition accuracy and system availability on customers' perceptions of a speech-enabled Interactive Voice Response (IVR) system. Fifty-six participants searched for bank rate information using a prototype speech recognition banking system in one of four conditions: (1) perfect system performance when obtaining rate information, (2) occasional speech recognition errors, (3) occasional loss of system availability, and (4) a combination of recognition errors and loss of system availability. A "system trust" measure was a better discriminator between conditions than a commonly-used subjective satisfaction measure: participants who experienced periods of unavailable service trusted the system less than those who experienced fully available service, but these groups reported similar subjective satisfaction rates. Participants who encountered speech recognition errors reported no lower levels of trust or satisfaction than those who experienced perfect recognition accuracy. The paper discusses the relationship between system trust and the willingness to use self-service systems, as well as special aspects of speech recognition systems in terms of "persona" and users' perceptions.
Does Rotary Pursuit Data Predict Mouse Task Performance A Pilot Study BIBAFull-Text 661-665
  Yuen-Keen Cheong; Son T. Pham; Lan T. Phan; Randa L. Shehab
Knight & Salvendy (1992) suggested that performance of mouse task depends on precision control and arm-hand steadiness. However, the claims lacked empirical support. This pilot study collected rotary pursuit data, measured by time-on-target (TOT), to assess participants' precision control ability. Performance of mouse task was operationalized using a Fitts' pointing task. Stepwise multiple regression revealed target diameter (D), distance amplitude (A), and TOT contributed to the variability of movement time (MT). Despite highly significant relations, the regression coefficients were so small that they offered little practical value. However, the results indicated that precision control ability is indeed predictive of the performance of mouse task. Several recommendations were made for subsequent studies, they include (i) psychomotor ability should be assessed using multiple trials, (ii) a wider range of ID values should be tested with, (iii) a multi-directional Fitts' paradigm should be employed, and (iv) the mouse task should be more representative of the direct manipulation paradigm.
The Effect of Information Overhead On Perceived Workload and Learning BIBAFull-Text 666-670
  Diego Rivera
E-commerce sites today contain variety product information to inform shoppers about a company's products offerings. Although the number of attributes used to describe products depends on the product being described, attributes can be in the hundreds. One of the key business challenges is to maintain the ever increasing product information up-to-date. It is important that data management tools used for these tasks are efficient and easy to use. The present study describes the effect of information overhead on perceived workload. Participants were asked to create 20 different products using four different web prototypes that varied in content density and customization capability. Mean time on task over 20 trials was fit using a power function and perceived workload was collected using NASA Task Load Index. The results obtained indicate that unused information does increase perceived workload and negatively affect performance. Also, that UI customization can help reduce perceived workload and allow users to reach peak performance faster. Finally, participants performed faster and with higher satisfaction under the customization conditions.
Enterprise Network Monitoring Using Treemaps BIBAFull-Text 671-675
  Joseph H. Goldberg; Jonathan I. Helfman
Treemaps may provide significant advantages over tabular data in corporate enterprise applications, due to their inherent ability to support users' integration of multiple dimensions of information. This study investigated the usability of treemaps for enterprise system administrators who monitor servers and web applications. Manipulated factors included hierarchy representation, data scale, and comparison with unsorted tables. The treemap hierarchy representations differed significantly in their support of the identification, comparison, and analysis tasks, but were significantly faster and more accurate than tabular data views. Treemap learnability was at least as successful as for tables. Performance differences between treemaps and tables increased with increasing size of datasets. Users' subjective ratings overwhelmingly supported treemaps over tabular data views. These results suggest that treemaps should be included as a standard graphical component in enterprise-level data analysis and monitoring applications.

COMPUTER SYSTEMS: Innovative Usability Methods

Proof of Concept For a Human Reliability Analysis Method For Heuristic Usability Evaluation of Software BIBAFull-Text 676-680
  Ronald L. Boring; David I. Gertman; Jeffrey C. Joe; Julie L. Marble
An ongoing issue within human-computer interaction (HCI) is the need for simplified or "discount" methods. The current economic slowdown has necessitated innovative methods that are results driven and cost effective. The myriad methods of design and usability are currently being cost-justified, and new techniques are actively being explored that meet current budgets and needs. Recent efforts in human reliability analysis (HRA) are highlighted by the ten-year development of the Standardized Plant Analysis Risk HRA (SPAR-H) method. The SPAR-H method has been used primarily for determining human-centered risk at nuclear power plants. The SPAR-H method, however, shares task analysis underpinnings with HCI. Despite this methodological overlap, there is currently no HRA approach deployed in heuristic usability evaluation. This paper presents an extension of the existing SPAR-H method to be used as part of heuristic usability evaluation in HCI.
Development and Validation of a Symmetry Metric for Interface Aesthetics BIBAFull-Text 681-685
  Michael P. Bauerly; Yili Liu
This article describes the experimental investigation of the effects of symmetry on judgments of interface aesthetics. Thirty compositions were developed in order to validate symmetry quantification algorithms with subjective aesthetic ratings. The same compositions were used in two experiments, one using basic black-and-white images, and the other using web pages. The images were rated by 16 subjects in each experiment using the ratio-scale magnitude estimation method against a benchmark image. Subjects also established an ordered list of the images according to their aesthetic appeal using the balanced incomplete block (BIB) ranking method.
   The results show that subjects are adept at rating symmetry about both horizontal and vertical axes and their ratings closely match the quantification algorithm. Additionally, the relation between the dominant symmetry value and aesthetic appeal shows that subjects preferred symmetric images over non-symmetric images for the black-and-white imagery. The development and validation of the symmetry metric is an important step towards developing quantitative evaluation metrics for interface aesthetics evaluation and design.
Analysis of Collaborative Meetings in Developing Data Mining Models BIBAFull-Text 686-690
  Jiao Ma; Colin G. Drury
Observations of group meetings were used to help our understanding of the Data Mining (DM) process, which can take a year to complete. Over a course of three months, we followed two collaborative groups and observed their weekly meetings, where they devised DM models and explored new ways to analyze and present microarray data. The study furthered the current understanding of the DM activities by revealing its socio-technical aspects, and directed a promising design approach for a more efficient and effective DM system. Field observations of collaborative meetings disclosed that a longitudinal study is, in fact, appropriate and necessary to further understand the DM process and the system.
Factor Analysis of Card Sort Data: An Alternative to Hierarchical Cluster Analysis BIBAFull-Text 691-695
  Miranda G. Capra
Software and product designers use card sorting to understand item groups and relationships. In the usability community, a common method of formal statistical analysis for open card sort data is hierarchical cluster analysis, which results in a tree of the items sorted into distinct, nested clusters. Hierarchical cluster analysis is appropriate for highly structured settings, like software menus. However, many situations call for softer clusters, such as designing websites where multiple pages link to the same target page. Factor analysis summarizes the categories created in card sorts and generates clusters that can overlap. This paper explains how to prepare card sort data for statistical analysis, describes the results of factor analysis and how to interpret them, and discusses when hierarchical cluster analysis and factor analysis are appropriate.
Revealing What's Important to the User: Value-Focused Thinking BIBAFull-Text 696-700
  Janet E. Miller; Chris McGee
Despite the importance of software interfaces, trade-offs must be made during development. Value Focused Thinking (VFT) provides an objective methodology that is well suited for handling multi-objective problems such as interface design issues. Facilitated sessions are held with the intended users to elicit what is of importance to the user. These values are characterized and put to a common scale, allowing measurement of their contribution to the overall objective. The resulting hierarchy can be used to guide software development or compare different interface solutions. In this study, a VFT hierarchy was developed with military intelligence analysts to identify what values were desired in an interface for software intended to address a facet of data overload. The prototype interface was evaluated against the hierarchy with these stated values. The process and the hierarchy itself provided insight on where resources should be expended to provide the greatest benefit in the final product.


The Effects of Line Length on Reading Performance of Online News Articles BIBAFull-Text 701-705
  A. Dawn Shaikh; Barbara Chaparro
Previous research has shown that typographical factors of online text may influence its readability. This study examines the effects of line length on reading speed, comprehension, and user satisfaction of online news articles. Twenty college-age students read news articles displayed in 35, 55, 75, or 95 characters per line (cpl) from a computer monitor. Comprehension was assessed using six question types -- title, main idea, main factual, structure, incidental, and recognition (Dyson & Haselgrove, 2001). Results showed that passages formatted with 95 cpl resulted in faster reading speed. Structure questions were found to be more challenging overall when compared to factual and other lower-level questions. Overall satisfaction was not affected by line length; however, users indicated a strong preference for the extreme line lengths.
Evaluation of Mouse Pads Designed to Enhance Gaming Performance BIBAFull-Text 706-710
  Jeremy Slocum; Shelby Thompson; Barbara Chaparro
In recent years, competitive computer gaming has enjoyed a rise in popularity. Marketers of gaming accessories make claims as to how their product can improve user performance. An experiment was conducted examining three specialized mouse pads. Results indicated no performance difference between the specialized mouse pads, a traditional mouse pad and no mouse pad. No significant differences were found between each of the mousing surfaces based on kinematic data. The results suggest that manufacturers claim of increased performance can not be supported by empirical evidence.
Comparing Computer Input Devices Using Kinematic Variables BIBAFull-Text 711-715
  Jeremy Slocum; Alex Chaparro; Daniel McConnell; Michael Bohan
Throughput (TP) is a global measure of input device efficiency but provides little information about user's movement behavior when interacting with a device. Psychomotor models of movement provide a framework from which to develop new "during" movement variables that can be used to explain why efficiency differences occur. Data from a previous study examining the usability of a mouse, trackball and RollerMouse was re-examined using TP and the kinematic variables peak velocity of the primary movement (PV) and proportion of total distance traveled in primary phase (%PMD). Partial correlation analysis found %PMD and PV to be significantly related to TP and negatively related with each other, suggesting a "speed/accuracy" tradeoff. Further analysis confirmed the variables were useful in discriminating between devices and found that the most efficient device was less constrained by the "speed/accuracy" tradeoff. It was concluded that kinematic variables offer a useful way of understanding efficiency differences between devices.
Perceptions of Personality in Computer Agents: Effects of Culture and Gender BIBAFull-Text 716-720
  Sasanka Prabhala; Jennie J. Gallimore
Developing computer agents with personalities may be one way to enhance human-machine collaboration. To create computer agents with personalities it is essential to identify the actions, language, and/or behaviors that people indicate signify the personalities are perceive. Additionally it is possible that culture and gender may play a role in how computer personalities are perceived. This research investigated how culture and gender affect the perception of computer personalities within a computer game. Participants were asked to rate the computer characters in a blackjack game based on the Big Five Factor personality trait model and to describe the actions, language, and/or behaviors that gave them their impressions. The results show that participants did perceive personality in the computer characters and were able to describe actions, languages and behaviors leading to their perceptions. The results indicated that there were no statistically significant differences based on culture and gender differences. This research provides a starting point for development of computer agents with personalities incorporating personality theory into model development.
Trend Analysis of the International Journal of Human-Computer Interaction from 1989 to 2004 BIBAFull-Text 721-723
  John Neumann; Jennifer M. Ross; Peter Terrence; Mustapha Mouloua
This report looks at the research trends over the years 1989-2004 as published in the International Journal of Human Computer Interaction (HCI). Over this time period, there has been a concerned focus by scholars and practitioners to bring issues such as interface design, usability engineering, human information processing, and user-centric system development into the mainstream consciousness of engineers and developers. Our research aims to provide information to both scholars and developers on the past and current trends in the growing field of HCI. Using the PsycINFO journal database, we compiled an extensive Excel workbook containing relevant information on all the articles appearing in the journal since its inception. We were then able to classify each document using the ACM SIGCHI taxonomy, developed by Hewett, et al. This taxonomy permits classification of articles based on six factors, within one of 17 possible categories. Several other dimensions were examined including year & period of publication (1989-1993; 1994-1999; 2000-2004), author affiliation, geographic location, number of empirical studies per paper, and average sample size per study. We also reported the classifications of each article as reported by PsycINFO. Besides noting the clear growth in the total number of articles published each period, our results indicate that the field of Human Computer Interaction has seen changes in research focus. Current trends point to an increase in research focusing on developmental processes, usability evaluation methods, human communication and interaction, and applications. Another trend shows a notable decrease in empirical studies using human participants over the 15-year period.

DEMONSTRATIONS: Demonstrations of Novel Interfaces

Advanced Interfaces to Support Continuous Planning and Re-Planning During Tactical Operations BIBAFull-Text 724-727
  Kevin B. Bennett; Lawrence Shattuck
A research program to develop decision support for mobile Army commanders has resulted in a prototype interface. This interface was developed using principles of Cognitive Systems Engineering, and initial evaluations were very positive. This demonstration showcases recent design efforts to support re-planning during tactical operations, which are extremely demanding and critical for mission success. Unfortunately, these activities have received relatively little attention from the research community. The prototype interface has been designed to assist the commander in performing these activities. This interface highlights key elements of the battle plan (i.e., the intended course of events), the battle execution (i.e., the actual course of events as they unfold over time), and the differences between them.
MIRP: A Wearable Tool for Evaluating Effectiveness of Information Display BIBAFull-Text 728-731
  John F. Stokes; Marlene A. Devine
Traditional approaches to HMI design focus on the use of visual displays and manual inputs, but these do not take advantage of the full range of means by which humans can perceive and interact with their environment. For wearable computing systems, the selection of modalities depends greatly on the proper consideration of human cognitive capabilities. The Multimodal Interface Research Platform (MIRP) is a wearable platform for evaluating task-relevant human performance by presenting information using three modalities: Visual (via head mounted display), Auditory (via earphones), and Haptic (via four vibrating actuators on the shoulders). Within the context of a predetermined task scenario, MIRP is able to monitor and record the user's interactions with the system and collect reaction time and a coarse accuracy determination of whether a message was understood. This enables observations about simple reaction time with respect to different alert/message modalities, as well as inferences about their understandability.

DEMONSTRATIONS: Demonstrating Design for the Virtual and Real World

Virtual Field Trips: Synthetic Experiences and Learning BIBAFull-Text 732-736
  Alicia D. Sanchez; Haydee M. Cuevas; Stephen M. Fiore; Janis A. Cannon-Bowers
Founded on the principles of experiential learning and anchored instruction, Virtual Field Trips utilize state-of-the art technologies to create immersive, multi-sensory, interactive experiences with real world environments. Virtual Field Trips are designed to be an integral part of a technology-enabled educational system to teach targeted material and motivate students.
Ergonomics: Leadership During the Product Design Process BIBAFull-Text 737-741
  Hugh E. McLoone
On a relatively short 2-hour flight to attend focus groups for a new project, my thoughts and feelings flowed out of my mind through my fingertips into these series of chapters. I was traveling with colleagues -- some new to the product design process -- and the same issues between designers, ergonomists, and product planners and their integrated product design process appeared again, as they had in past projects. Based on experience of shipping many, many products, I had assembled these rules of thumb about co-creation between ergonomists, designers and project team during product design process. The continuous need to transfer knowledge is essential to timely success of a distinct, valuable, useful, desirable, and usable product. Likewise, sharing these ideas on design process would also create opportunity to prompt discussion among teams composed of ergonomists and designers about the design process, leadership, and vision. I trust the ideas presented forthcoming will spark some thinking on the readers' end as well.
Demonstration: Advancing Robotics Research Through the Use of a Scale MOUT Facility BIBAFull-Text 742-746
  A. William Evans; Raegan M. Hoeft; Sherri A. Rehfeld; Moshe Feldman; Michael Curtis; Thomas Fincannon; Jessica Ottlinger; Florian Jentsch
This demonstration serves as an introduction to the CARAT scale MOUT (Military Operation in Urban Terrain) facility developed at the Team Performance Laboratory (TPL) at the University of Central Florida (UCF). Advances in automated military vehicles require research to understand how best to allocate control of these vehicles. Whether, discussing uninhabited ground vehicles (UGVs) or air vehicles (UAVs), many questions still exist as to the optimum level of performance with respect to the ratio of human controls to vehicles. The scale MOUT facility at UCF allows researchers to investigate these issues without sacrificing large costly equipment and without requiring vast physical areas, within which to test such equipment. This demonstration provides an introduction to the scale MOUT facility, describes the basic need for this tool, presents its advantages over full size counterparts, as well as several other possible uses for the facility.

EDUCATION: Teaching Team Behavior to Human Factors/Ergonomics Students, Part II: Specifics for Forming and Developing Teams, and Using Peer Ratings

Teaching Team Behavior to Human Factors Ergonomics Students, Part II: Specifics for Forming and Developing Teams, and Using Peer Ratings BIBAFull-Text 747-750
  Nancy J. Stone; William F. Moroney; C. Shawn Burke; Barrett S. Caldwell; Don B. Chaffin
Many Human Factors/Ergonomics specialists are members of work teams. To prepare students for teamwork, the students' educational experiences need to include team building exercises and experiences. As a follow-up to the 2004 HFES panel on teaching team behavior, this panel will address more specific aspects of teaching team behavior to HF/E students. In particular, the panelists will address the issues of forming teams, developing teams, and collecting and using peer ratings. The results of this and last year's panel discussion will be used to develop guidelines for effectively teaching teamwork to HF/E students. These guidelines will be disseminated through the Education Technical Group.

EDUCATION: Education Potpourri

The Need for Quality Aviation Safety Graduates: An Educational Challenge BIBAFull-Text 751-754
  Thomas R. Weitzel; Thomas R. Chidester; Roger A. Mason
The authors investigated a previously unaddressed problem within curricula of the United States (U.S.) aviation institutions of higher education. Graduates of these institutions were not being prepared to work within safety departments of the U.S. air carriers involved with one or more of the five current, voluntary Federal Aviation Administration (FAA) programs. To ascertain the need for a solution, a subjective instrument was developed and personally administered to 13 participants within the industry. The qualitative results were interpreted, and, in combination with the knowledge gained from the immersion of a professor within a research organization, resulted in the curricular placement of some of the aforementioned content on one campus of one U.S. aviation university during the spring semester of 2005.
Web-Based Distance Learning Technology: Does Appearance Matter BIBAFull-Text 755-758
  Cristina Pomales-Garcia; Yili Liu; David Mendez
This research examines the impact of several aesthetic/appearance characteristics of web-based distance learning environments on information recall and perceived content difficulty. Six web-based instructional modules were used, which consisted of fragments of different lectures, each containing a different topic and ranging between three to six minutes in length. The results show that appearance/aesthetic judgments do matter and they offer additional insights into the effectiveness of instructional methods beyond traditional performance measures. In this study the appearance/aesthetic judgments changed as participants were exposed to a series of modules over time in a way that is different from the corresponding performance changes. The integration of aesthetic/appearance judgments in the evaluation of web-based distance learning technology gives us valuable insights to deepen our understanding of what characteristics of the technology make it more appealing and successful.
The Validity of Human and Computerized Writing Assessment BIBAFull-Text 759-763
  Ronald Laurids Boring
This paper summarizes an experiment designed to assess the validity of essay grading between holistic and analytic human graders and a computerized grader based on latent semantic analysis. The validity of the grade was gauged by the extent to which the student's knowledge of the topic correlated with the grader's expert knowledge. To assess knowledge, Pathfinder networks were generated by the student essay writers, the holistic and analytic graders, and the computerized grader. It was found that the computer generated grades more closely matched the definition of valid grading than did human generated grades.
Incremental Transfer and Cost Effectiveness of Ground-Based Flight Trainers in University Aviation Programs BIBAFull-Text 764-768
  Esa M. Rantanen; Donald A. Talleur
Use of ground-based flight training devices in flight training is attractive for several reasons. In addition to undeniable safety aspects and immunity to weather, ground trainers also offer benefits in terms of training effectiveness, typically measured by the time or number of trials saved over training exclusively in an airplane. A review of 19 studies from the past 56 years that have investigated transfer of training effectiveness from ground trainers to airplane revealed, however, that unambiguous conclusions about the best use of these devices are difficult to discern. The reason for the lack of valid data and widely varied results are the large number of intervening variables present in flight training as well as the difficulty of conducting sound research on this topic.
Improving the Usability and Effectiveness of Online Learning: How Can Avatars Help BIBAFull-Text 769-773
  Hua Wang; Mark Chignell; Mitsuru Ishizuka
This paper describes Empathic Tutoring System (ETS) which uses character agents for online learning. Eye movement tracking and other physiological measures are used to personalize character agent behaviors (affective and instruction) in an e-learning environment. A prototype system reacts to learner's eye information in real-time, recording eye gaze and pupil dilation data (plus heart rate and skin conductance) during learning. Based on these measures, character agents inferred the attentional and motivational status of the learner and responded accordingly with affective and instructional behaviors. Character agents engage and direct the learner's attention while providing both generalized system help and personalized advice about the learning content. Feedbacks from preliminary usability studies may suggest that e-learning character agents reacting to eye gaze and physiological measures may heighten learner concentration and lead to more effective learning.


A Students Guide to HCI Research and Database Development BIBAFull-Text 774-777
  Lauriann M. Jones; Mustapha Mouloua
This paper is intended to provide a useful guide and reference for those students (or researchers) attempting to familiarize themselves with the large body of HCI research available. This paper discusses trends, labs, funding sources, implications, and major contributions to HCI over the past decade (1995-2005) as documented through the British Journal of Behaviour & Information Technology. Several graphs are provided to illustrate patterns of interest and publication of HCI research with step-by-step guidance for the overwhelmed student (or researcher) for everything from narrowing relevant HCI journals and articles to a sampling of funding sources. All in the hope of providing a guide to understanding what has been done in the field, where to get started, and the direction HCI research may be going in the future.
A Short History of HCI Research and Trends Published in the Journal Human Factors from 1984 to 2004 BIBAFull-Text 778-782
  Ruthann Savage; Sally Stader; Patricia L. McNeese; Mustapha Mouloua
This study was undertaken to explore the history of the use of the term human-computer-interaction (HCI) over two decades of the journal Human Factors. Results show that while some work may have been accomplished in the first ten years, the work wasn't identified as HCI, except at a rate of approximately two articles per year. After 1995 the incidence in the use of HCI as a topical reference increased, and from 2001-2004 there were significantly more articles on this topic. The articles were written by scientists around the world, employed in all areas of the field. This research attempts to show how HCI has evolved over these 20 years, to identify any trends in the research, and to provide suggestions for future research, including search methodologies. Specific information will be provided to use in planning future work, such as procedures, descriptions of apparatus, dependent variables and other methodological information.
Designing Human Factors Courses With a Human Factors Mind BIBAFull-Text 783-787
  Dahai Liu; Angela Baskin; Frances Greene; Christina Frederick-Recascino
Human Factors is a discipline that studies the body of information about human capabilities and limitations for engineering design. Human Factors combines different Engineering areas and integrates them with human information into the engineering design. This applied and multidisciplinary nature of Human Factors in turn requires that education in Human Factors should also focus on the application of knowledge to design, and encourage hands-on exercise into the learning process. A new course "Design With a Human Factors Mind" was designed to demonstrate this concept. This course abandoned the traditional classroom lecture format, using labs, field trips and guest lectures instead to expose students with various Human Factors subjects. A survey study was conducted to assess the efficiency of this teaching style. Results showed that different teaching techniques have different effects on students' performance. This case study provides some preliminary results for different teaching styles and can help other educators to design effective teaching methods in Human Factors education.
Placement Opportunities for Human Factors Engineering and Ergonomics Professionals in Industry and GovernmentMilitary Positions BIBAFull-Text 788-792
  Taylor J. Anderson; Deborah L. Bakowski; William F. Moroney
During the period from January 2004 through December 2004, the Placement Service of Human Factors and Ergonomics Society distributed announcements describing 115 new positions available for human factors and ergonomics professionals. This paper describes the 92 placement opportunities in Industry and the Government/Military. The attributes of the position descriptions examined include: employment sector, degree requirements, work experience, expertise, salary, and geographic location.
   The type of industry seeking most employees was Consumer Products at 16%. The degree required was usually a Masters (43.5%) and the geographic area with the most jobs was the Northeast (N=15). The area of expertise most frequently requested by employers was Human Computer Interaction (N=50). Human Factors/Ergonomics (N=22) was the most commonly specified job expertise.
   During the period from October 25, 2004 through December 25, 2004, forty-three announcements for new positions were listed on HFCareers.com. Findings are discussed separately for the HFES Placement Service and HFCareers.

ENVIRONMENTAL DESIGN: Environmental Design Features: Inside & Outside the Workspace

Does Ergonomic Chair Design Affect Thermal Comfort BIBAFull-Text 793-797
  Alan Hedge; Masaya Saito; Jason Jagdeo
The effects of foam, mesh and gel chairs on thermal comfort and productivity were investigated. Thirty-six subjects, 18 men and 18 women, were tested in same-sex triads with each subject sitting on one of the 3 chairs for 1.5 hours. Subjects wore light clothing (shorts, t-shirt, socks and sneakers) with a low clo value. Skin and body temperature were measured. Thermal comfort votes and body thermal data were collected every 30 minutes. Climate conditions were controlled (air temperature of 22.4°C ± 0.1°C and 21.1% ± 1.0%relative humidity). Results showed a gender difference in thermal comfort, women voted that the environment was significantly cooler than did men by the end of the experiment. There were no differences between the chairs in thermal comfort votes, skin and body temperatures, body movements or productivity.
Computer Display Viewing Angles: Is It Time to Shed a Few Degrees BIBAFull-Text 798-802
  Paul Allie; Cynthia Purvis; Doug Kokot
The angle at which a computer display is viewed may have an impact on the musculoskeletal and visual comfort of the user. Although scientific literature regarding viewing angles has grown in the past decade, a research gap still remains. As a result, one is challenged to design workstation solutions that satisfy the performance requirements of both the musculoskeletal and visual systems, and at the same time, adapt to individual preferences. The following recommendations are offered based on a "middle ground" approach where research findings regarding eye comfort, neck comfort and user preferences are all taken into account: (1) the top of the display screen should be placed at or lower than 5° below the horizontal line of sight; and (2) the center of the display should be positioned no more than 25° below the user's horizontal line of sight. These recommendations create a viewing angle range that is less than current recommendations stated in ergonomic standards for VDT workstations.
A Critical Analysis of the Usability and Design of Aluminum Wheelchair Ramps BIBAFull-Text 803-807
  Ilene B. Zackowitz; Alison G. Vredenburgh; Alan Hedge
A common method to improve accessibility for pedestrians and wheelchair users is the widespread use of ramps. Ramps for handicapped access are required by the Americans with Disabilities Act. The ADA has specific guidelines for many aspects of ramp design. Although these specifications detail ramp requirements, they do not necessarily guarantee that a ramp will be trouble-free for users. A recent study that evaluated how wheelchair users perceive differences in slope and cross slope revealed design problems for modular aluminum ramps. The purpose of this paper is to identify aluminum ramp design issues that resulted in usability difficulties for wheelchair users in that study. When designing an environment, it is critical that the wide range of users test it. This paper demonstrates that attempting to provide greater accessibility in one area may create new barriers in another.
Sitting or Standing for Computer Work Does a Negative-Tilt Keyboard Tray Make a Difference BIBAFull-Text 808-812
  Alan Hedge; Jason Jagdeo; Anshu Agarwal; Kate Rockey-Harris
The effects of using an electric height-adjustable worksurface, with and without the addition of a negative-tilt keyboard tray, on wrist posture, comfort, typing performance and body movements was studied. Eighteen subjects experienced four test conditions: typing while sitting with the keyboard on a flat surface or negative tilt keyboard tray, and standing with the keyboard on a flat surface or negative tilt keyboard tray. Results show that the most neutral typing wrist posture (least wrist extension) was maintained when sitting rather than standing. There was a slight wrist posture benefit with the negative tilt tray for both sitting and standing. Sitting with a negative-tilt tray was the most comfortable condition. Sitting was more comfortable than standing. No performance differences between conditions were found. When sitting there was more foot movement than when standing. When standing there was more weight shifting than when sitting.
Evaluating the Effects of Frost Heave on the Feasibility of Compliance with Existing Walkway Accessibility Standards BIBAFull-Text 813-817
  Alison G. Vredenburgh; Kevin Williams
Existing American standards specify criteria for maximum walkway running and cross-slope. Many regions of the United States experience seasonal weather changes. Winter snow can cause frost heave of concrete that can change the slope of concrete sections throughout the year. The current study evaluates the extent of these seasonal changes on walkway slope. The findings indicate that the fluctuation of running and cross-slope makes it impossible to comply year-round with existing standards.

ENVIRONMENTAL DESIGN: Environmental Workspace Issues and Organizational Culture: In Offices, Retail, and Manufacturing Settings

Effects of Reducing Enclosure on Perceptions of Occupancy Quality, Job Satisfaction, and Job Performance in Open-Plan Offices BIBAFull-Text 818-822
  Jay L. Brand; Thomas J. Smith
Results from two field studies are reported: a quasi-experiment of changing from 60-64 inch to 36-42 inch partition heights at a multi-national corporation, and a comparison of two office areas at a global manufacturer. In the first study, both control and experimental participants endured moving, but only the experimental group experienced any change in partition height. A quantitative, subjective survey provided work environment ratings before, immediately after, and six months after the change. The results show that in general, this was a negative change for users, although some non-significant trends suggested that -- defined at the group level -- one or two outcomes may have been positive. Using a much more extensive instrument, the second study found several differences in occupant ratings of workplace design as a function of differences in the physical environments. A framework is outlined for interpreting these results in terms of individual (i.e., privacy) and group (i.e., communication) needs.
Thermal Effects on Office Productivity BIBAFull-Text 823-827
  Alan Hedge; Wafa Sakr; Anshu Agarwal
A field study was conducted to investigate the associations between indoor thermal conditions and productivity for computer workers in an insurance company. Thermal environment conditions and productivity were logged every 15 minutes for 9 women workers for 16 consecutive work days. Results showed an association between thermal conditions and productivity, which was highest when conditions fell in a thermal comfort zone and lowest when conditions fell below this zone. The findings have important implications for the design and management of workplaces.
Functional Characteristics of Users in Tasks Associated with Grocery Retail Checkout: A Literature Review BIBAFull-Text 828-831
  David A. Ringholz
The intent of this literature review is to examine existing research on functional characteristics and limitations of individuals engaged in tasks associated with grocery retail checkout. The resulting data will be used to generate performance criteria to guide the development of grocery retail checkstands and facilitate comparisons between highly varied populations. Target populations for this study are wheelchair users, standing users, elderly individuals and women who are pregnant. Comparing the characteristics of these individuals can contribute to understanding of key user requirements for this and related tasks in addition to providing a context for future research in the area of retail workstation optimization through the application of universal design principles.
Ergonomic Evaluation in a Beverage and Food Service Application BIBAFull-Text 832-836
  Joseph Cohen; Andrew S. Imada
A global beverage and food company contracted the authors to evaluate the current store design to enhance speed of service and minimize the potential for employee injury. This assessment involved observations, interviews, physical measurements and link analyses at three high-volume locations in Southern California and three international stores in Singapore and Malaysia. The study examines two frequently performed tasks (preparation of café latte and mocha ice blended beverages). While the design was deemed to be adequate for the tasks performed, the analysis identified six areas for improvement. Further, the analysis included macroergonomic considerations for management control and organizational culture.
Ergonomics Implementation, The Right Way and the Wrong Way BIBAFull-Text 837-840
  Boris Povlotsky
This paper illustrates some of author's views of the ergonomics implementation challenges within diverse industries, manufacturing, office environments, and machinery/product design. We intend to analyze and review the roots of problems from different perspectives and recommend which ergonomics approaches are likely to succeed or fail. Most importantly it is imperative to find the actual cause(s) of obstacle(s) -- problem(s) before looking for appropriate ergonomics solution(s) and acceptance of ergonomics innovations by end users.
   The presented material is based on the substantial authors' experiences in human factors engineering and ergonomics, in industry and academia and in various countries.
   Our objective is to present an integrated view of ergonomics within corporate bureaucracy in the contexts of favorable and unfavorable environments -- factors that lead to success or failure.


Impact of Environmental Design Features: Does Color Scheme Influence Transputed Attributions BIBAFull-Text 841-845
  Sae Lynne Schatz; Clint A. Bowers; Heather C. Lum
Businesses invest millions in their environmental designs, hoping that they will communicate "the right" message and influence consumers' perceptions and behaviors. This investment is based on a set of beliefs that are widely held in the design community; however, there has been little attempt to validate them. As a first effort towards validation, we conducted a two-part study. We examined designers' beliefs about the impact of room color, in general, and evaluated the specific anecdotal principle that deep, red hues appear expensive. The results suggest that beliefs regarding the behavioral affects of color are quite prevalent. For the second part of the study, we created three illustrations of a restaurant, each featuring various shades of red. Sixty-two participants rated their opinions of the restaurants. The results suggest that a discrepancy exists between designers' beliefs and the public's reactions. We recommend the use of attribution theory and policy-capturing to resolve this.

FORENSICS PROFESSIONAL: Practice and Research in Forensic Human Factors

Evaluation of Threat by Police Officers: Initial Findings BIBAFull-Text 846-849
  Karen A. Delos Santos; Shawn C. Stafford; James L. Szalma
Police officers' threat perception of static images was examined using images reflecting the range of five threat categories on which police officers are trained. Thirteen experienced officers from a police departments in the southeastern United States participated in this study. Officers rated their perceived threat level for 110 images that were presented to them on a laptop computer. Each of these images was rated twice by each officer. Officers used all five categories to rate the stimuli, and their responses to the extremes (images rated as 1 or 5) were faster than responses to more ambiguous stimuli in the other categories. These results were generally consistent with predictions based on Fuzzy Signal Detection Theory. Further studies will evaluate performance with these images in the context of a signal detection task. Once fully developed, this tool could be used to evaluate new recruits' decision-making process before given the green light to carry a badge. These assessments could also be used as a modified training tool for experienced officers if the stimuli were to be placed in a semi-immersive environment.
Fatal Errors: Case Study Involving Medication Labeling BIBAFull-Text 850-853
  H. Harvey Cohen; Cindy A. LaRue
Our forensic human factors firm was retained to research the facts and formulate an opinion about a series of errors that resulted in an incorrect intravenous bag being used on a hospitalized patient. The patient died as a result of the administration of this drug. We were asked to explore the issue of errors made in administering medications and to provide an opinion specifically regarding the labeling of the subject intravenous bag product. In the process of exploring those issues, we also assessed the frequency of this type of error involving product labeling and packaging of drugs and why these errors are made by trained professionals. From our research into medical error statistics, theories of human error, and design principles for product labels, we provided recommendations for improving the labeling and packaging which, if implemented, would most likely help to reduce these types of errors.
A Case Study in Forensics, Macroergonomics, and Work-Related Musculoskeletal Injuries in Call Center Work BIBAFull-Text 854-857
  Joseph Cohen; H. Harvey Cohen
This case study describes a personal injury case and expert opinions expressed by a HF/E expert concerning work-related musculoskeletal injuries sustained by a 43 year-old female call center service representative. The circumstances surrounding this case are unusual as it involves a suit brought against an employer by an employee in the State of California, a physically adequate workstation design, and a cumulative rather than acute injury. The HE/E expert examined the deposition testimony, interview data and reviewed the literature as part of his analysis and concluded that the scientific literature establishes a link between the known organizational stress factors existing at the defendant's workplace and symptoms of work-related musculoskeletal disorders. Furthermore, the defendant's ergonomics safety program was deficient in proactively dealing with the plaintiff's injuries. The HF/E expert's analysis and testimony ultimately proved important in establishing liability on the part of the defendant.
The Development, Application, and Limitations of 3D Human Simulations in Fall Accidents BIBAFull-Text 858-861
  Gary David Sloan
A tool that predicts the trajectories of linked human body segments on the basis of their inertial properties could be useful in the analysis of fall accidents. In order to be of value in forensic applications, relevant attributes of both the plaintiff and accident site must be modeled at some requisite level of fidelity. By systematically varying different attributes of the model, e.g., avatar posture, body segment velocity, coefficient-of-friction between modeled treads and footwear, it is possible to examine the likely consequences on body-segment trajectories. Trajectories and collisions can then be compared with patterns of injury, plaintiff testimony, and witness accounts.
Consumer Beliefs Toward the Protection Offered by Motorcycle Helmets: The Effects of Certification, Price, and Crash Speed BIBAFull-Text 862-866
  William J. Vigilante
This study examined consumer beliefs towards the level of protection offered by motorcycle helmets varying in price (35, 60, 120, 240); level of certification (none, DOT, SNELL, both DOT and Snell); and at high versus low speed lay-down type crashes. Fifty-eight motorcycle riders and passengers were surveyed. The results indicated that consumers believe the level of protection offered by motorcycle helmets is dependent upon certification level more than price; and the expected severity of injury during a crash has little or no relationship to the helmet's certification or price. The implications of these findings include: motorcycle helmets with the same certification should provide the same level of protection regardless of price, or different levels of certification should be provided that represent the actual level of protection offered by the helmet. Finally, consumers should be provided with more education on the actual level of protection they can expect from a helmet based on its certification.


Consequences of Poor Workplace Layout and Ambient Conditions: Case Study of an Industrial Injury BIBAFull-Text 867-871
  H. Harvey Cohen; Cindy A. LaRue
Our firm was retained to consult on a lawsuit involving an injury sustained by an employee of a food processing plant. While performing an assigned, yet unfamiliar task, the employee unintentionally stepped into an uncovered sump well containing water in excess of 140 °F (60 °C), seriously burning one leg. The sump well had been uncovered for routine maintenance by another employee who neglected to put the lid on the well when he had completed his task. This case went to litigation with the plumbing contractor, general contractor and boiler company as defendants. This paper will provide a human factors/ergonomics analysis of the incident, describing the facility design and maintenance issues, as well as the human and system errors that led to the injury. Also discussed are recommendations based on human factors principles that would have decreased the likelihood of the incident occurring.
Intersection Right-of-Way: What Is an Immediate Hazard BIBAFull-Text 872-875
  T. J. Ayres; R. Kelkar; K. B. Kennett
Vehicle codes require that a driver entering an intersection should yield right-of-way if an approaching vehicle is close enough to be an immediate hazard. This paper discusses a framework for contributions from human factors and vehicle kinematics to right-of-way questions, based on defining immediate hazard as a situation requiring an aggressive avoidance maneuver. A variety of issues that arise can be addressed with existing technical literature, while others suggest a role for further empirical research. Quantitative analyses reveal the relative importance of factors such as distance perception, response latency and initial speed.

GENERAL SESSION: General Sessions Potpourri

Canine Factors: Bridging the Gap Between Human Factors and Comparative Psychology BIBAFull-Text 876-880
  William S. Helton
Working dogs have proven to be highly accurate and flexible extensions of our human senses. These trained dogs are increasingly employed in a multitude of occupational roles. The study of these highly trained working dogs bridges the gap between Human Factors and Comparative Psychology and offers many points of potentially fruitful exchange. The present paper presents two examples of issues where Human Factors and Comparative Psychologists share a common interest: expertise development and sustained attention. Dogs are, perhaps, unique among non-human animals in their adaptation to human culture and are amazingly flexible, often serving as human surrogates. Many issues discussed and investigated in the Human Factors literature are also relevant to the study of working canines and the study of working canines may enhance the Human Factors literature.
Why and How HFE Professionals Can Better Use Theory (Metatheory Included; Some Assembly Required) BIBAFull-Text 881-885
  Mark E. Koltko-Rivera; Peter A. Hancock
The relationship between theory and discipline is problematic for human factors and ergonomics (HFE). We address the following constituent issues: (a) the present state of theory usage in HFE; (b) the reasons underlying this state; (c) the need for theory in HFE; (d) what HFE professionals (including educators, journal editors, and individual researchers) should do to encourage the proper use of theory; and, (e) the outlines of a metatheory of HFE. A metatheory is a general framework that may help professionals to construct more useful specific theories. Our metatheory of HFE involves five basic units, or classes of variables: task, environment, personnel, tool, and performance. Each unit in turn has multiple components (i.e., specific variables). Use of the metatheory is illustrated with specific examples. Our hope is that researchers will be motivated to make explicit and useful connections between their research and necessary theory, to the improvement of both; the metatheory may be useful in this endeavor.
Assessing Daily Stress with the Short Stress State Questionnaire (SSSQ): Relationships with Cognitive Slips-Failures BIBAFull-Text 886-890
  William S. Helton; Diana Fields; Joseph A. Thoreson
Stress is an important aspect of operational settings. This article presents a study providing further psychometric and validation evidence of a short multidimensional self-report measure of stress state, the Short Stress State Questionnaire (SSSQ; Helton, 2004) based on the Dundee Stress State Questionnaire (DSSQ; Matthews et al., 1999, 2002). Participants filled out the SSSQ twice daily for 70 days, once in the morning and once at night. They also reported daily cognitive slips-failures. Chain-P Factor Analyses of the individual items for both pre and post assessments were conducted and the relationships between the SSSQ factors and daily self-reported cognitive slips-failures were examined. The factor analyses, as previously indicated by Helton (2004), differentiated three aspects of subjective stress: Task Engagement, Distress, and Worry. Daily post-Distress and post-Worry correlated moderately with cognitive slips. The 24-item SSSQ appears to be a reliable measure of daily stress state, potentially useful in naturalistic studies.
Two Dimensional Finite Element Modeling to Identify Physiological Bases for Tactile Gap Discrimination BIBAFull-Text 891-895
  Gregory J. Gerling; Geb W. Thomas
Tactile edge and gap detection are fundamental to performing manual tasks. Because slowly adapting type I (SA-I) mechanoreceptors encode details pertinent to edge localization, understanding low-level encoding is critical to understanding edge perception. Solid mechanics models may help us understand how mechanoreceptors in the skin encode applied surface indentation into neural signals representing edges. Finite element models test whether an indenter separated by a gap creates unique stress/strain distributions in models based upon orientation to fingerprint lines. Results indicate that a gap axis parallel to ridge lines elicits a more pronounced signal than a gap axis perpendicular to ridge lines. The differences may be due to underlying intermediate ridge microstructure. The percentage differences for three derived stress metrics range from 30-87% greater when the indenter's gap axis parallels the ridges. This initial effort demonstrates that underlying skin microstructure may aid tactile perception of stimulus orientation.
Variations in Perceived Emotional Intensity by Levels of Anthropomorphism in 3D Modeling BIBAFull-Text 896-900
  Thomas D. Fincannon; Tim Smoker; Michael Pate
The purpose of this study was to examine various levels of anthropomorphism on perceived intensities of emotion with 3D computer images. Previous research has indicated that less attention to detail in virtual environments and lower levels of anthropomorphism in images result in greater levels of presence and social presence respectively. Images were designed to be happy, sad, or neutral in both high and low anthropomorphic conditions. Participants observed the images and rated the intensity of the expressed emotion on a 7-point Likert Scale. The intensity of expressed emotion for happy and sad conditions was averaged for each participant. Using this average, the low anthropomorphic condition reported significantly greater intensities of emotion than the high anthropomorphic condition. There were no significant differences between high and low anthropomorphic conditions of the neutral face.

GENERAL SESSION: Levels of Automation in the Brave New World: Adaptive Automation, Virtual Presence, and Swarms, Oh My!

Levels of Automation in the Brave New World: Adaptive Autonomy, Virtual Presence and SwarmsOh My BIBAFull-Text 901-905
  Christopher A. Miller; Scott Galster; Gloria Calhoun; Tom Sheridan; Raja Parasuraman; Robert Smith; Ryan Proud; John Reising
The concept of Levels of Automation (LOAs) as a categorization of distinct combinations of human-automation relationships arrayed along, usually, a spectrum of possibilities has a long and fruitful tradition in Human Factors. Nevertheless, if a proliferation of novel LOA schemes and uses is any evidence, there is some reason to perceive unrest and dissatisfaction with comparatively simple LOA schemes that have been proposed in the past. This panel will review concepts and uses of Levels of Automation schemas and discuss their relative strengths and weaknesses. A central theme will be whether novel automation capabilities (and, therefore, novel human-machine interaction opportunities) demand revisions to LOA concepts or whether we can (or have) defined a scheme that defines the full space of possible interaction types.

GENERAL SESSION: Homeland Security

Human Factors in Homeland Security: Symposium Overview BIBAFull-Text 906-907
  David A. Thurman; Thomas F. Sanquist
Building on the "Cognitive Factors in Intelligence Analysis" symposiums held at HFES in 2003 and 2004, this symposium focuses on a range of human factors issues across the homeland security domain. Papers in this session come from human factors practitioners engaged specifically human factors research in the homeland security arena, including intelligence analysis, personnel selection, inspection and screening, and public perception of the risk/privacy tradeoff.
Helping Analysts Deal with Data Overload: Profiling Profilers BIBAFull-Text 908-912
  Cynthia Dominguez; Donald Cox; William G. Long; Brian Moon; Gary Klein
Intelligence analysts provide an incredibly important service toward maintaining our national security. They are chartered with providing the knowledge basis for decisions our national and military leaders make. Analysts must be depended upon to influence high-risk, time-critical, sometimes life-or-death decisions; thus, supporting their requirements is a vital goal for research and development efforts. In this paper, we focus on the cognitive aspects of analysts' information collection and filtering tasks, particularly of all-source analysts who continuously monitor message traffic. These analysts create synthesized reports for customers. We will discuss the issue of data overload and its effects, along with current lines of research on information retrieval. We end with a summary of our research effort examining filtering/profiling, to include approach and initial findings, towards our eventual goal of developing design seeds that can be incorporated into software tools to better support analysts' cognitive work.
The Human Element in Homeland Security Systems: Application Issues and Research Needs BIBAFull-Text 913-917
  Thomas F. Sanquist; David A. Thurman; Heidi A. Mahy
Increased federal emphasis on homeland security in the past four years has created unprecedented monitoring and vigilance requirements for the people involved in operating and administering technologies used to detect and interdict potential terrorist activity. A broad range of agencies using a variety of non-destructive imaging and data synthesis systems have placed a variety of new mental demands on Department of Homeland Security (DHS) personnel, such as TSA screeners, Customs and Border Protection (CBP) officers, and intelligence analysts from various agencies. This paper reviews selected DHS-administered technologies and systems based on open-source information, describes some of the human factors issues associated with these systems, and suggests potential interventions and research approaches to ensure acceptable human-system performance. The advantages of a DHS-wide programmatic focus on applied human-systems research is discussed.
Metrics for Evaluation of Software Technology to Support Intelligence Analysis BIBAFull-Text 918-921
  Jean Scholtz
For the past two years we have been involved in evaluation of software technologies designed to improve intelligence analysis. We have been conducting evaluations both in the laboratory and in operational environments. While usability is an important aspect of software for intelligence analysis, our work has gone beyond usability and focused on utility. We have been using top-down and bottom-up procedures to develop metrics and evaluation methodologies, including literature reviews and expert opinions, laboratory studies, baseline creation, and field observations. Our laboratory work has focused on strategic, open source analysis. Our field work to date has been more in the tactical area all source domain. In this paper, we discuss a number of metrics we have developed and outline some issues involved in evaluation of software to support intelligence analysts.
Factors Contributing to Airport Screener Expertise BIBAFull-Text 922-926
  Marvin McCallum; Alvah Bittner; Joshua Rubinstein; James Brown; Joel Richman; Randal Taylor
An airport X-ray Screener Test Battery was developed to better understand how selected aspects of screeners' visual and perceptual capabilities, attentional and verbal processing, work schedule, medication use, work history, training, equipment knowledge, personal style, attitudinal characteristics, and job satisfaction are related to job performance. The Test Battery was administered to 92 X-ray screeners and analyses compared Test Battery performance with X-ray screening job performance. Analyses suggest that important factors related to X-ray screening performance include several aspects of perceptual and attentional processing; screeners' time on the job; screeners' work schedules; and their use of pharmaceuticals, over-the-counter drugs, and dietary supplements. Potential applications of the findings for improving screener performance through personnel selection, training, workforce management, and X-ray equipment design enhancements are discussed. Ongoing research is also outlined.
Towards an Adaptive Question Answering System for Intelligence Analysts BIBAFull-Text 927-931
  Andrew J. Cowell; Alan R. Chappell; David A. Thurman
Battelle is working in partnership with Stanford University's Knowledge Systems Laboratory (KSL) and IBM's T.J. Watson Research Center to develop a suite of technologies for knowledge discovery, knowledge extraction, knowledge representation, automated reasoning, and human information interaction, in unison entitled "Knowledge Associates for Novel Intelligence" (KANI). We have developed an integrated analytic environment composed of a collection of analyst associates, software components that aid the analyst at different stages of the analytical process. In this paper, we discuss our efforts in the research, design and implementation of the question answering elements of the Information Interaction Associate. Specifically, we focus on the techniques employed to produce an effective user interface to these elements. In addition, we touch upon the methodologies we intend to use to empirically evaluate our approach with active intelligence analysts.

GENERAL SESSION: Beyond Requirements: Improving Software Tools for Intelligence Analysts

Beyond Requirements: Improving Software Tools for Intelligence Analysts BIBAFull-Text 932-935
  Sarah Geitz; Brian Moon; Anita D'Amico; Robert R. Hoffman; Rob Page
The goal of this panel is to discuss critical human factors concerns in the development of software for intelligence analysts. The panel presentations are designed to provide a high level overview of the software development process, the intelligence analysis process, and the challenges encountered in both obtaining user feedback. Presentations will examine a variety of issues including the analysis of imagery, text, information assurance, data fusion, visualization models and in establishing situational awareness, as well as empowering analysts with open source software.
   The panel discussion will focus on extracting generic processes that can be applied to obtaining more accurate software metrics, requirements and solutions from a world where certain topics cannot be discussed. Methods and metaphors for better describing to individuals working outside of the classified world the context a within which a tool will be used, may be touched upon, as well as identifying ways of overcoming both internal and external politics. Human factors concerns may also be addressed, such as evaluating how trust affects the feedback received from individual analysts and communication and interaction within and between groups of analysts. Identifying and overcoming potential perceptual problems in the software development process will also be discussed.
   The anticipated outcome of the panel will be to target individual processes, techniques and technologies that can be applied to obtaining requirements to support cognitive processes, which can in turn be applied developing software tools that better fit the needs intelligence analysts.


The Influence of Driver Stress, Partial-Vehicle Automation, and Subjective State on Driver Performance BIBAFull-Text 936-940
  Gregory J. Funke; Gerald Matthews; Joel S. Warm; Amanda Emo; Angela N. Fellner
The present study addressed the effects of stress, partial-vehicle automation, and subjective state on simulated vehicle driving. 168 college students participated. Participants in the stress-induction condition completed a 'winter' drive which included periodic loss-of-control episodes. Participants in the no-stress-induction condition were not exposed to loss of control. Participants then completed a test phase, during which they drove in one of three conditions varying in level of automation. Manipulation checks demonstrated that both the stress manipulation and level of automation influenced subjective state. Driver performance data were analyzed by means of hierarchical multiple regressions. Vehicle automation but not the stress induction influenced performance. In addition, individual differences in subjective task engagement and worry were associated with performance. Resource theory provides a framework that partially but not completely explains the impact of stress factors on performance. Data further show that analysis of individual differences is essential for predicting the effects of stress factors.
Making Human Factors Truly Human: Cultural Considerations in Human Factors Research and Practice BIBAFull-Text 941-945
  Katherine Lippa; Helen Altman Klein
Traditionally, human factors research has been conducted in Western nations to answer the questions of Western practitioners. This approach was appropriate in the past and still works well in many situations. However, as the world of work is becoming more international it is important to consider how national differences affect human factors applications. We review recent issues of the Human Factors journal to see how cultural differences are being addressed in research. Five domains where important cultural difference may influence research findings are reviewed. These areas are physical design, visual displays, symbolic communication, information technology and managing complex processes. We present recommendations for incorporating greater cultural variation into Ergonomic and Human Factors work.
Publishing Trends of the Journal of Human Factors from 19972004 BIBAFull-Text 946-950
  Michael Curtis; Thomas Fincannon
Following up on previous analysis of characteristics of articles in the Journal of Human Factors, the current paper is intended to present a current analysis of articles published from 1997-2004. The paper examines all published articles across the following characteristics: year of publication, period of publication, general affiliation of authors, specific affiliation of 1st author, country of origin of authors, technical group, and collaboration comparisons. This information illustrates the important contributors to research in the field, how much research is done within each technical group, and the characteristics of collaborative work produced. By making comparisons within the eight year period and comparing total data to previous trend analysis (Zavod & Hitt, 2000) this paper will illustrate the direction of human factors research. The information reported can provide a reference for professionals, students, and prospective researchers in identifying where research is taking place and burgeoning topics of interest.

HEALTH CARE: Reducing Health Care Errors

Reducing Health Care Error BIBFull-Text 951
  Marilyn Sue Bogner; Sonja Koneczny; Christian Erbe; Ulrich Matern; Mark Scerbo
There Is More to Error in Healthcare Than the Care Provider BIBAFull-Text 952-954
  Marilyn Sue Bogner
Typically when an error occurs in healthcare, the care provider is considered the cause. Because that person committed the act that lead to the adverse outcome efforts to address the error are directed to that person. Indeed, human factors practitioners have developed remedial training and their medical device design activities have emphasized user interface design. This paper presents the case for expanding that focus based on the realization that the act of committing an error is a behavior and behavior reflects the interaction of the person and factors in the environment. The counterintuitive findings that more errors occur in prescribing medications with computer order entry than with handwritten script are discussed in terms of this approach.
Checklists Suitable Tools for Usability Testing BIBAFull-Text 955-959
  S. Koneczny; U. Matern
Ergonomics in the operating room (OR) is an unsolved problem for users and engineers. Deficiencies of the OR as a workplace cause potential hazards for the patient as well as for the OR staff. To detect those conditions a checklist for the OR was developed and as a first step evaluated in a German hospital. Medical technical devices were found to be lacking in usability due to such as unclear symbols, impracticability, hindrances and insufficient ease in handling. Also the positioning of devices in the OR shows ergonomic problems that in most cases necessitates an unavoidable awkward working posture for the employees that causes pain. The checklist can be used as a basic tool for the implementation of usability into the engineering process and design of new medical devices as well as for the usability testing of the final product.
The Position of the German Association of Biomedical Engineering on Ergonomics in Medical Technologies BIBAFull-Text 960-964
  U. Matern
With an increasing employment of technology the medical quality of treatment may rise. But, at the same time, the complexity of the medical equipment rises as well. This leads to an increase of the required interactions between user and technology. Therefore, a higher work loading for the medical and nursing personal is consequential. New requirements to the safety and the quality of use of medical devices and systems result from the increasing employment of technology. For the acquisition of devices users and operators need to pay attention to the possible sources of error in handling and use as well as to the possibility to decrease operating and process costs by foresighted purchase decisions. The German Association of Biomedical Engineering (DGBMT) considered the ergonomics of medical products as an important topic and established the Technical Committee of Ergonomics in Medical Engineering. The members of this technical committee compiled a paper describing the most important issues and intentions being partly presented in the following.
The Role of Human Machine Interfaces in Industrial Development of Medical Devices BIBAFull-Text 965-968
  Christian O. Erbe
Electrosurgery is a widely used modality for separation of tissue plains, achievement of hemostasis and devitalization of pathologic tissue structures. Although this technology has been used in almost every operating room in the world for many many decades, it still is recognized by leading clinical organizations as potentially the most dangerous device during surgery (1). In addition to technical problems, human error is recognized to be an important factor in those unfavorable outcomes, especially as during medical procedures electrosurgical systems are in close proximity to the physician-patient interface and physically in direct contact with both.
The Future of Medical Training and the Need for Human Factors BIBAFull-Text 969-973
  Mark W. Scerbo
Within the last five years, several events have taken place that will have a profound effect on the practice of medicine and patient safety. First, medical virtual reality simulators have been developed for training minimally invasive and other forms of surgical procedures. Second, evidence is beginning to show that surgeons who train with this technology are more skillful when they operate on genuine patients. Third, several regulatory agencies will soon begin to require this technology for training and certification. At present, most medical virtual reality simulators have been developed with little or no human factors involvement, but the need for human factors knowledge and expertise is paramount. In this paper, I describe what I perceive to be the top 10 areas where human factors professionals can contribute to the evolution and adoption of this new technology.

HEALTH CARE: Design Issues in Health Care Systems

Transition from An Open Bay to a Private Room Neonatal Intensive Care Unit Design A Human Factors Evaluation BIBAFull-Text 974-978
  Thomas J. Smith; Sandra Clayton; Kathleen Schoenbeck
This report summarizes findings from a human factors evaluation of a change in the design of a neonatal intensive care unit (NICU) from an open bay (OBNICU) to a private room (PRNICU) patient care environment. The objective was to compare and contrast effects of this design change on the perceptions and performance of NICU patient care staff. Results indicate that, relative to work on the OBNICU, staff perceived that work on the PRNICU resulted in notable improvements in the quality of physical environmental conditions, their jobs, patient care and patient safety, interaction with parents of NICU patients, interaction with patient care technology and their life off-the-job. In contrast, staff perceived that the quality of interaction among different members of the NICU patient care team worsened substantially after the move to the PRNICU. The latter finding prompted the recommendation that a virtual open bay environment be implemented in the PRNICU.
Home Cholesterol Test Kits: Helpful or Harmful BIBAFull-Text 979-983
  Deepti Surabattula; Craig M. Harvey; Jennifer C. Rood; Fereydoun Aghazadeh
A home health test kit is a medical test approved by the United States Food and Drug Administration that can be purchased without a prescription and used in the privacy of the house. Release of home health testing kits into the market has enabled people to take care of their own health. Misinterpretation of results and delays in treatments are the major concerns of the doctors. In the present study, two cholesterol test kits, Accuchek Instant plus and Home Access Instant Cholesterol Test, were compared. This research focused on user errors and clinical accuracy of the kits. The study was conducted with 30 participants, 15 men and 15 women. Participants tested their overall cholesterol level with both kits. In addition, a clinical cholesterol evaluation, the medical gold standard, was performed. The accuracy of both test kits was evaluated by comparing each of the test kit results with the clinical evaluation. The results of the study showed that inaccuracy of the test kit results did not depend on the type of the test kit used; however, the Accuchek Instant plus resulted in a greater correlation between the clinical results and test kit results regardless of the number of user errors.
Clinical information use by medical and nursing staff in the ICU: Outcomes of a coded tables analysis BIBAFull-Text 984-988
  Anne Miller; Penelope Sanderson
The long-term, intensive nature of patient admission to an Intensive Care Unit necessitates passing responsibilities from one medical and nursing staff member to another. An ideal outcome of this process is a common team situation awareness of the patient's condition. However, medical and nursing staff have different training and practice regimes, which raise questions about the nature of the situation awareness needed by the two groups. Statistical and an exploratory data analysis techniques were used to explore the information content of video-cued recall interviews in order to identify differences in information use. Doctors were found to attend to future patient projections over a broader range of physiological functions than nurses, reflecting a strategic orientation, whereas, nurses attended to sensed information over shorter timeframes than doctors, reflecting a tactical orientation. When not aligned these orientations may lead to breakdown in coordination and discontinuities in patient care.
A Cognitive User Centered Redesign of a Radiotherapy Chart BIBAFull-Text 989-993
  R. Sela; Y. Auerbach; Z. Straucher; M. Rogachov; O. Klimer; R. Bar-Deroma; R. Carmi; A. Kuten; S. Pollack; D. Gopher
We describe the human factors analysis and redesign of the radiotherapy paper chart used at the radiotherapy unit of Rambam Medical Center. The chart is a paper form used by multiple team members. It is the main record of relevant information and treatment orders. It also serves as the major follow up and quality control tool. As such, the chart is a major communication, reference and decision making aid, which has a direct influence on the treatment quality and patients safety and health. Analysis of the existing chart revealed multiple content and format design problems, which raise the probability of errors. The new design of the chart attempts to resolve these problems. At present, it has been adopted by the unit and hospital and is in the process of being produced and introduced to the unit.
Informing Accessible Design Through Self-Reported Quality of Visual Health BIBAFull-Text 994-998
  V. Kathlene Leonard; Paula J. Edwards; Julie A. Jacko
This study investigates the potential utility of the VFQ-25 as an alternative to clinically acquired measures of visual function for investigations of computer-based performance. While clinical measures of visual function have been used as predictors of performance on psychomotor tasks for people with impaired vision, the VFQ-25 represents a low cost, easy-to-administer alternative. In this study, participants with Age-related Macular Degeneration and controls responded to the VFQ-25 and completed a drag-and-drop task with different feedback modalities. Based on VFQ scores, a hierarchical clustering algorithm was used to generate five distinct participant groups. Statistical comparisons of performance between the groups under each feedback condition confirmed the efficacy of the VFQ-25 as a tool for classifying user interaction. Consistent with previous studies comparing performance based solely on visual acuity, these results encourage the use of the VFQ-25 in research and design in circumstances that are not conducive to gathering clinically acquired measures.

HEALTH CARE: Decision Making and Mental Workload in Health Care Systems

Toward Improved Communication in Laparoscopic Surgery: Accounting for Multiple Frames of Reference and Mental Rotations BIBAFull-Text 999-1003
  Cristina Rivera; Caroline G. L. Cao
This work is an examination of barriers to communication between the attending and assisting surgeons during laparoscopic surgery, where the same image of the surgical site is viewed from different vantage points with respect to the patient. Part of the problem lies with the multiple frames of reference each surgeon holds, and the mental rotations each must perform to construct a common frame of reference for communication and collaborative work. An experiment was conducted to demonstrate the effects of display-control incongruency on the performance of an aiming task in a simulated laparoscopic environment. Aiming performance was best when the camera was oriented at 0° perspective and worsened as the angle of deviation from 0° increased. Performance was affected to a greater degree by viewing perspectives from the left of the subject than viewing perspectives from the right. Results also suggest that when surgeons are facing each other, as is the case in many laparoscopic surgeries, one surgeon's performance will be worse than the other's. The mismatched display-control perspectives are compounded by ambiguous spatial references in verbal communication. From these findings, a case can be made for the importance of vocabulary that forces a common frame of reference during laparoscopic surgery.
An Investigation of Medical Decision Making Bias Using Patient Penal Status BIBAFull-Text 1004-1008
  Stephane Timothee; Marc L. Resnick
When providing medical care, doctors are constantly required to make complex decisions based on a wide variety of information sources. As the US health care system becomes more complex with managed care, new regulations for prescription drugs, and other factors, it will become easier for bias to be introduced into the decision making process. This study investigates medical treatment decisions and seeks to identify paths through which bias can be introduced. Patient penal status was used as a proxy for patient variables that in theory should not affect care decisions but in practice often do. The results of the study show that penal patients are less likely to receive required and recommended treatments and that these differences are not due to differences in race, age, or gender of the prisoner population. Additional research is needed to identify the organizational or contextual factors that lead to differences in the provision of medical care.
Spatial Orientation Using Echolocation Characterising Signals for Downconversion BIBAFull-Text 1009-1013
  T. Claire Davies; Shane D. Pinder
Individuals with visual impairments sometimes use echolocation for spatial orientation and obstacle detection. An advantage to echolocation is the ability to determine the location of obstacles without physical contact. Echolocation has essentially become obsolete with the increase in environmental noise. If echolocation could be performed at ultrasound and downconverted directly to the auditory domain, visually impaired travellers may be better able to spatially orient. As a first step in this project, we needed to determine auditory signals that could have the potential to allow us to extract meaningful spatial information from the environment. To do this, we evaluated different possible clicks for obstacle detection, examined the ability to determine wall distance with low and high frequency sounds, and finally we used low and high frequency sounds to quantify feedback echoes as a spatial environment changes. This preliminary work showed that echoes that are carried on a higher frequency carrier can be downconverted to produce similar signals to those produced when echoed in the auditory domain directly.
Perceived Mental Workload in an Endocopic Surgery Simulator BIBAFull-Text 1014-1018
  Martina I. Klein; Michael A. Riley; Joel S. Warm; Gerald Matthews
Endoscopic surgery -- a procedure wherein a target organ is displayed on a monitor and physicians use graspers to manipulate the tissue -- has benefits for patients in terms of reduced blood loss, infection, and pain. However, physicians' informal reports indicate that this type of surgery is challenging to perform. These challenges arise from the need to view the target tissue on a monitor, resulting in reduced depth information as well as a disruption of the normal hand-eye mapping. This study represents the initial experimental effort to assess the workload demands experienced in an endoscopic surgery simulator using the NASA-Task Load Index (TLX), a well validated workload measure, and the Multiple Resource Questionnaire (MRQ), a newly developed workload scale. The TLX revealed that the workload experienced in the simulator was indeed high. Additionally, the MRQ revealed different workload profiles associated with different levels of hand&-eye mapping disruption.
Identifying Performance Obstacles Among Intensive Care Nurses BIBAFull-Text 1019-1023
  Ayse P. Gurses; Pascale Carayon
In this paper, we compare findings of two studies aimed at identifying performance obstacles among intensive care nurses. The first study is a qualitative study where data was collected from 15 intensive care nurses using individual, semi-structured interviews. The second study is a cross-sectional study conducted among 298 nurses from 17 intensive care units (ICUs) of seven hospitals using a questionnaire survey. Based on the results of these two studies, the most commonly experienced performance obstacles among ICU nurses include inadequate help from others, tools and equipment, ineffective inter-provider communication, materials and supplies, poor physical work environment, and family issues. The results of these two studies have implications regarding efforts aimed at redesigning ICU work organization in order to reduce nursing workload and improve quality of working life and quality and safety of care.

HEALTH CARE: Usability Issues in Medical Systems

A Usability Evaluation of An Infusion Pump by Nurses Using a Patient Simulator BIBAFull-Text 1024-1028
  Allison Lamsdale; Susan Chisholm; Roger Gagnon; Jan Davies; Jeff Caird
Using a high-fidelity patient simulator, this study had nurses evaluate the advanced features of an intravenous (IV) infusion pump being considered for purchase by a large Canadian health region. Three use cases or scenarios were developed, based on known difficulties administering multiple drugs through separate IV lines and the potential for certain drugs (e.g., heparin) to contribute to adverse outcomes in patients if the drug dosage was incorrectly calculated. After an in-service training session with the pump, thirteen nurses performed the use cases on an Emergency Care Simulator, which displayed a range of vital signs. During the sessions, nurses were required to use a think-aloud protocol, verbalizing all steps they were performing. The most common problems found were with the "Change Mode" and the "Select New Patient" features. Use of the On/Off switch was identified as a common strategy to clear pump information and to escape incorrect navigation paths. The consequential contribution to patient safety of these problems ranged from non-hazardous to potentially very hazardous. A number of design recommendations were made to address problems that were identified with the pump's hardware and software configurations, as well as to any in-service provided to new pump users.
Evaluation of a Bed Assistive Device on Self-Perceived Recovery Measures for Patients in Postoperative Care BIBAFull-Text 1029-1032
  Grace M. Tran; Kari Babski-Reeves
Assistive equipment has helped lower task demands and back stress for patient-handlers; however, limited research exists on the psychological benefits (i.e., safety and comfort) of self-transfer devices for patients in postoperative care. A study was conducted to determine the efficacy of a bed assistive device in a patient population; the objectives were to compare self-perceived recovery measures and usage of pain medication between patients in the Control (n= 8; age, 34 ± 6.3years) and Device (n =7; 41 ± 12) groups. Fifteen female participants undergoing either abdominal hysterectomy (n = 6) or Cesarean-section (n = 9) procedures were recruited for the study. Both groups completed a total of twelve questionnaires over a five-week recovery period. The Device Group reported higher levels of energy, less pain interference, lower perceived pain, less reliance on pain medication and returned to activities of daily living faster than the Control Group.
Evaluation of Drug Label Designs Using Eye Tracking BIBAFull-Text 1033-1037
  Agnieszka Bojko; Catherine Gaddy; Gavin Lew; Amy Quinn
Eye movement measures and conventional performance metrics were used to compare existing drug labels to a new label template that was created based on human factors principles and user research. Twenty pharmacy practitioners were asked to locate a particular drug among others using sets of existing labels and their redesigned counterparts. For most tasks, the new design led to faster responses, either due to a decrease in the number of fixations required to complete a task or a decrease in the mean fixation length. The number and sequence of fixations within a single label and across labels (used as indicators of search efficiency) and fixation duration (used as a measure of information processing efficiency) provided insight into the origins of the noted speed improvements, helping assess which of the multiple design changes introduced in the new template had impact on performance. Application of eye tracking to redesign evaluation is discussed.
Technology Characteristics Predicting End User Acceptance of Smart Intravenous Infusion Pumps BIBAFull-Text 1038-1041
  Tosha B. Wetterneck; Pascale Carayon; Folasade Sobande; Ann Schoofs Hundt
Technology acceptance is an important predictor of end user technology usage. Perceptions of technology characteristics relating to usability and technical performance are particularly important to understanding user acceptance. This paper reports on the implementation of Smart intravenous infusion pumps at a tertiary care hospital. Nurse user perceptions of the technology usability (five dimensions), technical performance, and acceptance were measured one month after implementation. Overall, 42% of nurses responded positively towards accepting the pump. For 21 of 23 usability characteristics and performance questions, nurses were more likely to report neutral perceptions than positive or negative perceptions. The highest positive perceptions were for ease of learning to operate the pump and reliability of the pump. Six characteristics predicted end-user acceptance. Perceptions that the IV pump enhanced job effectiveness, made the job easier, increased safety of care, and functioned as expected predicted higher acceptance, while perceptions that alarm messages were frustrating and the pump interface was rigid predicted lower acceptance. Therefore, a new finding provided in this study is that highlighting improved patient safety when hospitals implement Smart intravenous infusion pumps may improve user acceptance of the pump.
Usability Evaluation of a Mobile Ecological Interface Design Application for Diabetes Management BIBAFull-Text 1042-1046
  Jordanna Kwok; Catherine M. Burns
Healthcare applications for small-screen mobile devices are becoming increasingly common for medical professionals and patients. Even so, usability issues including navigation and screen clutter remain a challenge. Ecological Interface Design (EID) was used to design a patient-oriented diabetes management display for Java-enabled mobile devices, making it one of the first mobile EID (mEID) applications. This paper presents a usability evaluation of the diabetes management application, which compares the mEID display to a modified task-based display (mEID+Task). The mEID+Task display integrates functional task characteristics such as frequency and necessity; menu structure, item ordering, item labelling, and input scheme were varied. Results showed that normalised trial completion times were moderately faster in the mEID+Task display than in the mEID display, while no differences were observed in trial completion accuracy. Furthermore, the mEID+Task display received higher preference ratings than the mEID display alone. The findings suggest that the usability of mEID displays can be improved by incorporating a task-oriented approach.

HEALTH CARE: Medical Systems and Training

Effects of Video Game Experience on Laparoscopic Skill Acquisition BIBAFull-Text 1047-1051
  Sara L. Waxberg; Steven D. Schwaitzberg; Caroline G. L. Cao
The apprenticeship model used to teach surgical residents is no longer adequate, especially in laparoscopic surgery training. The other alternatives available, such as simulators or animal models, can be expensive and difficult to implement. This study was conducted to explore the effect of videogame experience on surgical skill acquisition. We hypothesized that a week of videogame playing would improve performance on a surgical skills trainer and that performance on the videogame would reflect performance on the trainer. Thirty participants were tested in a between-subjects mixed design. Results were inconclusive. However, the use of videogames for training may be justified given the minimal cost. The idea of training surgeons using an inexpensive technology that is familiar, and that is fun and engaging at the same time, has considerable potential for the field of training in surgery.
Work System Analysis of Home Nursing Care and Implications for Medication Errors BIBAFull-Text 1052-1056
  Calvin K. L. Or; Gail R. Casper; Ben-Tzion Karsh; Patricia F. Brennan; Laura J. Burke; Pascale Carayon; Anne-Sophie Grenier; Carolyn Krause; Judy Murphy; Margaret Sebern
The purpose of this study was to examine the context of the provision of home nursing care for patients with congestive heart failure. A modified macroergonomic analysis and design work system analysis was undertaken in two phases with fourteen nurse participants: I) field observations of eight nurses for the collection of data on work elements and II) follow-up telephone interviews with six home care nurses. Open-ended questions were asked after the observations to identify clinical knowledge, policies, and procedures that influenced care decisions and practices. The telephone interviews focused on four different aspects of home health care delivery and were conducted using semi-structured questions. Results of the observations were translated into flowcharts and a summary report. The baseline findings described aspects of home medication management and its relevance to safety, quality of care, communication, and self-management.
Handoffs During Nursing Shift Changes in Acute Care BIBAFull-Text 1057-1061
  Emily S. Patterson; Emilie M. Roth; Marta L. Render
Handoffs during the nursing shift change were directly observed on two acute care wards each of a private and public hospital, for a total of 236 patient updates by 49 nurses during 14 shift changes. Data from the three wards which conducted audio-taped updates were transcribed. The transcriptions and field notes were analyzed for the existence and frequency of 21 strategies used in high reliability organizations. In addition, we iteratively categorized the interruptions, questions, and statements made during the updates. Finally, we iteratively categorized stances towards decisions communicated during the updates. Implications of the findings are discussed.
Examining Issues in Communicating Patient Care Information Across Shifts in a Critical Care Setting BIBAFull-Text 1062-1066
  Joseph Sharit; Lorgia McCane; Deborah M. Thevenin; Paul Barach
This study addresses issues associated with sign-out reports occurring during shift changes in the pediatric intensive care unit of a large metropolitan hospital. The issues include the need for organizing our knowledge concerning the types of errors that providers are susceptible to during the sign-out process, the roles of personality, experience, and cultural factors, particularly as they may affect the incoming provider's inquisitiveness, and the potential impact on patient care of various different methods of performing sign-outs. We observed eight outgoing nurses and four residents who gave sign-out reports, and conducted eight semi-structured interviews with nurses, residents, nurse managers, and attending physicians. The results revealed important and intricate relationships among many of the variables that were investigated and suggested a number of interventions that might improve the sign-out process. Overall, our data on shift change sign-outs in an acute care setting confirmed the resiliency of health care providers and their capability for managing patient care under extremely demanding conditions.
Human Factors Meets Anesthesia: Advanced Training to Improve Airway Management BIBAFull-Text 1067-1069
  Frank A. Drews; Ken Johnson; Noah Syroid; David L. Strayer
Enhanced training techniques have been successfully employed to improve performance in domains that require efficient multi-tasking skills. Some of these techniques include part task training (PTT) and variable priority training (VPT). PTT focuses on dividing complex tasks into small components followed by intensive concentrated training on each individual component. VPT focuses on optimal distribution of attention when performing multiple tasks simultaneously. The present study used VPT and PTT to train a group of first year anesthesia residents on airway management and compared performance of this group with a group of first year residents who participated in the standard curriculum. Preliminary results indicate that the group that received PTT and VPT is more successful in managing airway problems.

HEALTH CARE: Medical Devices and Safety

Robotic Surgery and the Operating Room Team BIBAFull-Text 1070-1073
  Fuji Lai; Eileen Entin
Robotic surgery has the potential to revolutionize the field of surgery and improve patient safety. However, despite the advantages robotic surgery can offer, there are multiple human factors-related issues that may prevent these systems from realizing their full benefit. This study identified some of the salient human factors issues and considerations that need to be addressed for integration of new technologies such as robotic systems into the Operating Room of the future. We conducted in-depth interviews with operating team members and other stakeholders who have experience with robotic surgery to identify workflow, teamwork, training, and other clinical acceptance issues. Addressing these and other human factors issues will help the integration of surgical robotic systems into use for the ultimate goal of improving patient safety and healthcare quality.
Studying and Supporting Collaborative Care Processes BIBAFull-Text 1074-1078
  Cynthia Dominguez; Paul Uhlig; Jeff Brown; Olga Gurevich; Wes Shumar; Gerry Stahl; Alan Zemel; Lorri Zipperer
In patient care today, teams of practitioners from various disciplines must coordinate their efforts in order to deliver care successfully. Frontline nurses and physicians must interact with social workers, therapists, physician assistants, nurse practitioners, and others to develop and carry out coordinated plans of care. Also, clinical team members must communicate with patients and their families in language that can be understood and acted upon. In support of these goals, JCAHO standards require patient care to be planned and provided in an interdisciplinary, collaborative manner. As hospital units develop processes for collaborative care in complex environments such as post-surgery and critical care units, it is important to understand what constitutes success for these processes and how they can be enabled and supported. This report documents a series of field visits and simulations designed to observe, videotape, and interview collaborative care team members, patients, and family members engaged in varying forms of collaborative practice. This ongoing research is being conducted by a multi-disciplinary team of medical and social scientists with a shared goal of studying and supporting collaborative care processes.
Clinical Reminders: Explaining Variability in Adoption by Nurses and Physicians at Four Outpatient Clinics BIBAFull-Text 1079-1083
  Jason J. Saleem; Emily S. Patterson; Laura Militello; Marta L. Render; Greg Orshansky; Steven M. Asch
Computerized clinical reminders (CRs) can improve compliance with evidence-based practices in preventive care and chronic disease management. However, observational research is needed to explain the known variability in the use of CRs. We conducted ethnographic observations of nurses and providers using CRs in outpatient primary care clinics for two days in each of four geographically distributed Veterans Administration (VA) medical centers. We found that use of CRs was impeded by (1) lack of coordination between nurses and providers, (2) using the reminders while not with the patient, impairing data acquisition and/or implementation of recommended actions, (3) workload, (4) lack of CR flexibility, and (5) poor interface usability. We discuss implications of these findings for CR system design and provide recommendations for redesign to facilitate the effective use of CRs.
Promoting Patient Safety Within Implantable Medical Devices: Patient Alert BIBAFull-Text 1084-1088
  Holly Vitense
Implantable Cardioverter Defibrillator (ICD) systems have been shown to provide lifesaving therapy for patients at risk of sudden cardiac death due to ventricular tachyarrhythmia. In order to assure an ICD system is operating properly, some models of ICDs perform periodic system checks. The Patient Alert feature, in Medtronic ICDs, monitors and alerts patients, via audible tones, to system integrity issues that have the potential to comprise patient safety.
   The objective of this research was to evaluate: how often patients are being alerted to ICD system issues, and how effective the alerts are at bringing patients into medical clinics for treatment and thus promoting patient safety. An analysis of 14,092 ICDs revealed that the probability of first alert occurrence increased with time since implant, but overall occurrence rates remained low (< 7% per patient year). The average median time from the alert sounding until the patient received medical attention was 4.3 days. Overall, for a life-threatening condition such as ICD therapy delivery being turned off, the majority (76%) of patients with this alert were brought into a clinic within one week to have therapy delivery turned back on. To reach the remaining patients, as well as bring all patients in quicker to seek medial treatment, additional communication modalities are being planned for the next generation of ICD systems.


Surgical Learning Aid: Reducing Uncertainty for the Novice During Simulated Minimally Invasive Surgery BIBAFull-Text 1089-1093
  Mathieu O. Gaulin; Caroline G. L. Cao
Can a procedural learning aid assist novice surgeons in reducing uncertainty and workload during critical points of minimally invasive surgery in an OR environment? Twenty Tufts University students performed a multi-step cutting task on a laparoscopic skills training simulator, with and without a multi-media procedural learning aid. A simple between subjects design was used. The results showed that those subjects who used a learning aid while completing the procedural cutting task were significantly faster (p = 0.02). However, subjects' perceived workload with and without the learning aid were not significantly different. These results have implications for the teaching of residents and communication between experts and novices in the OR.
Development of the Internet Clinical Communication Centre: a Patient Centered Application for Prostate Cancer Follow-up BIBAFull-Text 1094-1098
  Jennifer Wong; Joanne Hohenadel; Carlos Rizo; Alejandro R. Jadad
This project aims to provide selected follow-up healthcare services via Internet technologies. A user-centered approach and qualitative method of inquiry taken in the development of a prostate cancer Internet Clinical Communication Centre (iC3) to provide clinicians and patients access to portions of the electronic health record, illustrates the critical importance of security, privacy, and the patient-provider relationship.
Minimizing Movement Time in Surgical Telerobotic Tasks BIBAFull-Text 1099-1103
  R. Darin Ellis; Alex Cao; Abhilash Pandya; Anthony Composto; Michael D. Klein; Greg Auner
Surgical robotic devices are rapidly achieving widespread use and acceptance. Despite the many benefits of robotic-assisted surgery, it is typical for robot-assisted procedures to take longer. This study investigates the effect of control:response ratio on simple movement time in surgical telerobotic tasks. Robot control interfaces offer "motion scaling" settings but, in practice, this feature is often not used effectively, and is confounded by factors such as the fulcrum point of the laparoscopic instrument. Results using a simple aimed movement task indicate that control:response ratio indeed has a large effect on movement time, and further that it interacts with task difficulty. These results can guide medical device designers and the developers of surgical training protocols.

HUMAN PERFORMANCE: Kickoff Address: Human Performance Modeling -- A Historical Perspective

A Brief History of Normative Models of Human Behavior BIBFull-Text 1104-1108
  Thomas B. Sheridan

HUMAN PERFORMANCE: Human Performance Models of Pilot Behavior

Human Performance Models of Pilot Behavior BIBAFull-Text 1109-1113
  David C. Foyle; Becky L. Hooey; Michael D. Byrne; Kevin M. Corker; Stephen Deutsch; Christian Lebiere; Ken Leiden; Christopher D. Wickens
Five modeling teams from industry and academia were chosen by the NASA Aviation Safety and Security Program to develop human performance models (HPM) of pilots performing taxi operations and runway instrument approaches with and without advanced displays. One representative from each team will serve as a panelist to discuss their team's model architecture, augmentations and advancements to HPMs, and aviation-safety related lessons learned. Panelists will discuss how modeling results are influenced by a model's architecture and structure, the role of the external environment, specific modeling advances and future directions and challenges for human performance modeling in aviation.
Eye Movements in Human Performance Modeling of Space Shuttle Operations BIBAFull-Text 1114-1118
  Michael Matessa; Roger Remington
The goal of our research is to easily develop models that predict astronaut performance in space shuttle operations, but it is difficult to make extrapolations from astronaut training data. A solution is to decompose a complex task into a set of basic operators which are sequenced to create longer chains of behavior. In this modeling project, gaze durations and sequences are predicted and compared to the performance of novice (trained pilots) and expert (astronaut) space shuttle operators. The model makes generally good zero-parameter predictions of gaze durations, but there are notable discrepancies. The gaze sequence of the model is more similar to expert performance than novice performance, but there are differences from both. It appears that with more training, experts develop different gaze sequence strategies than novices due to familiarity with fault messages and procedures. Future modeling efforts should have their gaze sequence strategies based on expert performance.
Effects of Ride Motion on the Speed and Accuracy of In-Vehicle Pointing Tasks BIBAFull-Text 1119-1123
  Kevin A. Rider; Bernard J. Martin
Terrain-induced vibration of a moving vehicle adversely affects the ability to quickly and accurately perform in-vehicle pointing tasks by altering the planned fingertip trajectory. The relationship between movement speed and accuracy is a result of the combined use of visual and somatosensory feedbacks which are used to discern movement deviations and make necessary compensatory movements. Participants (N=20) performed three-dimensional rapid pointing tasks under stationary and ride motion conditions to three touchpanel displays. Ride motion contributed to increased reaction and movement times and increased endpoint variability. Trajectory deviations were correlated to the principal direction of vehicle acceleration. Reaches orthogonal to the dominant vehicle acceleration exhibited larger endpoint variability, and reaches to the elevated touchpanel resulted in the largest variability across all motion conditions. Principal axes of endpoint ellipses were along the on-axis and off-axis directions of fingertip movement.
Modeling the Effectiveness of Tools to Assist Sonar Operators BIBAFull-Text 1124-1128
  Michael L. Matthews; Jeff Bos; Jacquelyn M. Crebolder; Sharon McFadden
The task of building the underwater picture from sonar data is made complex by high volumes of noise and multiple data that arrive from a variety of acoustic sources detected at great distances by modern, sonar equipment. Typically, acoustic sources from ships have a complex spectrum consisting of several base frequency components and related harmonics. The task for operators is to analyse the data to determine if there is a pattern that represents the signature of a known source, thereby leading to identification of a vessel. Since the task can be highly labour intensive automated decision aids may be of value to the operator. This project addresses how to predict and optimise the impact of new technologies in system re-design by using a modeling/simulation approach to operator-system functionality. A generic sonar analysis process was simulated and the effectiveness of a decision aid evaluated. The improvement in performance predicted by the aid was then validated experimentally.
A Non-linear Relationship Between Controller Workload and Traffic Count BIBAFull-Text 1129-1133
  Paul U. Lee
Controller workload has been a focal topic in air traffic management research because it is considered a key limiting factor to capacity increase in air traffic operations. Because workload ratings are subjective and highly prone to individual differences, some researchers have tried to replace workload with more objective metrics, such as aircraft count. A significant caveat in substituting these metrics for workload ratings, however, is that their relationships are non-linear. For example, as the number of aircraft increases linearly, the controller's perceived workload jumps from low to high at a certain traffic threshold, resulting in a step-function increase in workload with respect to aircraft count, suggesting that controllers perceive workload categorically. The non-linear relationship between workload and aircraft count has been validated using data collected from a recent study on the En Route Free Maneuvering concept element (Lee, Prevot, Mercer, Smith, & Palmer, 2005). The results suggest that objective metrics, such as aircraft count, may not be used interchangeably with subjective workload. In addition, any estimation on workload should not be extrapolated from a set of workload measures taken from an experiment since the extrapolated workload is likely to significantly underestimate workload.
A Hybrid Agent-Control System Approach to Analyze Various Driving Behaviors BIBAFull-Text 1134-1138
  Stacy Lovell; James Melhuish
A large percentage of traffic problems occur due to risky or aggressive behavior by drivers (James, 2000). Aggressive driving, incidents of road rage, and following distance are some of the major concerns surrounding the issue, and are increasing in frequency and severity on America's roadways (Rathbone, 1999). An understanding of risky driving and its impact is required in order to help alleviate factors that contribute to these behaviors. Models of risky or aggressive behaviors of drivers allow us to study these effects and their impacts on highway safety, and can further help to identify levers (implicit and explicit) that influence these behaviors. This paper uses a cognitive agent model of human drivers as control systems to aid in the understanding of the effects of heterogeneous beliefs of risk, and the impacts of various driving behaviors on performance.

HUMAN PERFORMANCE: From Models to Methods to Models: Tools and Techniques for Using, Developing, and Analyzing Cognitive Human Performance Models

From Models to Methods to Models: Tools and Techniques for Using, Developing, and Analyzing Cognitive Human Performance Models BIBAFull-Text 1139
  Wayne D. Gray; Christopher W. Myers
Four modelers present tools based on or for cognitive human performance modeling. Myers introduces a new statistical technique for testing the similarity of sequential behavior across conditions. This technique promises to solve what Anderson (2002) regarded as the non-determinism problem of modeling behavior at the 100-ms level of analysis. John presents a programming-by-demonstration system that creates keystroke level GOMS models in ACT-R. Her approach enables those not trained in cognitive science to build predictive models of human performance. Salvucci's work expands on John's system by applying predictive modeling techniques to in-vehicle devices. His work integrates models of device use with a rigorous model of driver behavior to predict driver distraction and performance. Finally, Gray introduces Cognitive Metrics Profiling (CMP) -- a model-based approach that produces theory-based estimates of cognitive workload. CMP holds the promise of predicting transient changes in cognitive workload that occur in a dynamic task environment.
Computing the Similarity of Sequential Behavior BIBAFull-Text 1140-1143
  Christopher W. Myers
Current technology provides researchers' the capability to collect high-density/high-definition data. However, the potential of such capabilities is diminished without the availability of objective analyses. For example, techniques to objectively compare two complete behavioral routines, two subsections within the same routine, or two subsections between two different routines have been elusive. The capability to objectively compare interactive routines of behavior will enable researchers to study the adoption and evolution of such routines. In this paper a technique is proposed to objectively compare behavioral routines, whether the data are obtained from a human or embodied computational model. This technique offers the promise of solving what Anderson (2002) regarded as the non-determinism problem of modeling behavior at the 100-ms level of behavior. The technique is housed within a software tool for integrating and analyzing fixed-location and movement data collected from eyes and cursors, simultaneously (Myers & Schoelles, in press).
Cognitive Metrics Profiling BIBAFull-Text 1144-1148
  Wayne D. Gray; Michael J. Schoelles; Chris Sims
Cognitive Metrics Profiling promises a new approach to minimizing the cognitive workload of interactive systems. By metering high-fidelity computational cognitive models of embodied cognition, Cognitive Metrics Profiles provide a theory-based prediction of the transient changes in workload demanded by dynamic task environments. Although establishing the reliability and validity of this new approach will not be trivial, our profiles stand on the shoulders of the ACT-R architecture of cognition. More than 30-yrs of research have gone into the ACT line of theories. Over the last decade, hundreds of researchers have used ACT-R to build and test models of human cognition. Hence, although many of the details of the architecture are certainly incomplete, much of ACT-R is approximately correct. We expect that the predictions of a Cognitive Metrics Profile based on ACT-R will provide a better estimate of cognitive workload than the estimates used in current human factors practice.
Modeling Tools for Predicting Driver Distraction BIBAFull-Text 1149-1152
  Dario D. Salvucci
In contrast to the vast amount of modeling work focused on desktop user interfaces, recent work has increasingly focused on "off-the-desktop" interfaces, one prime example being in-vehicle interfaces used while driving. This paper highlights four recent approaches to predicting driver distraction from in-vehicle interfaces as secondary tasks: hand-crafted modeling with the full-fledged ACT-R architecture, hand-crafted modeling with the much less complex ACT-Simple framework, modeling-by-demonstration using the new CogTool, and simplified modeling-by-demonstration using the integrated Distract-R system. While all four use an integrated-model approach and a rigorous driver model, each approach illustrates different advantages and disadvantages of simplifying cognitive modeling for purposes of rapid prototyping and evaluation of in-vehicle interfaces.
Cognitive Human Performance Modeling by Demonstration BIBAFull-Text 1153-1156
  Bonnie E. John
Cognitive human performance models have enjoyed a rich history in human-computer interaction but have yet to make a widespread impact in system design, possibly because they are difficult to construct. We employed user-centered design techniques to develop a new tool that is easier to use than previous methods or tools. CogTool combines a familiar method of prototyping, modeling by demonstration, and the ACT-R cognitive architecture to enable user interface designers to make valid human performance models with little effort.

HUMAN PERFORMANCE: Current R&D in Human Performance Modeling

Non-Intrusive Measurement of Workload in Real-Time BIBAFull-Text 1157-1161
  Markus Guhe; Wenhui Liao; Zhiwei Zhu; Qiang Ji; Wayne D. Gray; Michael J. Schoelles
We present a new method to measure workload that offers several advantages. First, it uses non-intrusive means: cameras and a mouse. Second, the workload is measured in real-time. Third, the setup is comparably cheap: the cameras and sensors are off-the-shelf components. Fourth, we go beyond measuring performance and demonstrate that just using such measures does not suffice to measure workload. Fifth, by using a Bayesian Network to assess the workload from the various manifesting measures the model adapts itself to the individual user as well as to a particular task. Sixth, we use a cognitive computational model to explain the cognitive mechanisms that cause the differences in workload and performance.
Validation of Predictive Workload Component of the Multimodal Information Design Support (MIDS) System BIBAFull-Text 1162-1166
  Kelly S. Hale; Leah M. Reeves; Par Axelsson; Kay M. Stanney
Operators in military C4ISR environments are required to rapidly assess and respond to critical events accurately while monitoring ongoing operations. In order to assist in designing complex display systems to support C4ISR operators, it is critical to understand when and why information displayed exceeds human capacity. Common metrics for evaluating operator overload are subjective report, which rely on self-reporting techniques (e.g., NASA/TLX, SART). A new design tool, the Multimodal Information Design Support (MIDS) system, predicts times of operator overload and offers multimodal design guidelines to streamline cognitive processing, thus alleviating times of operator workload and optimizing situation awareness. This paper empirically validates MIDS' predictive power in determining situations which may cause operator overload by comparing MIDS output to subjective reports of workload and SA during C4ISR operations. Future studies will validate MIDS' design capabilities through redesign and evaluation of performance, workload and SA on the optimized C4ISR task environment.
Counting On ACT-R to Represent Time BIBAFull-Text 1167-1171
  Daniel N. Cassenti; Andrew L. Reifers
Temporal issues consistently factor into decisions, yet surprisingly few research studies have explored how to model temporal cognition. We developed an Adaptive Control of Thought -- Rational (ACT-R, e.g., Anderson & Lebiere, 1998) model to help account for how people estimate time, one of many issues in temporal cognition. According to the model, people adjust the lengths of words through abbreviation or extension and produce the words at a rate in tune with the rate of environmental events. This procedure allows an individual to synchronize with regular intervals of time in the environment and produce just-in-time responses to events. This type of approach incorporates a behavioral aspect to time estimation and an ACT-R model of temporal cognition that requires no changes to the architecture of ACT-R.
A Conceptual Framework for Dynamic Prioritization in Multiple-Task Scenarios BIBAFull-Text 1172-1175
  Guoxi Zhang; Robert G. Feyen
Prioritizing tasks appropriately is particularly critical when performing multiple tasks concurrently. Although necessary to achieve one's goals or avoid serious consequences, prioritization has not received much attention in the research literature, especially with respect to modeling human performance computationally. A conceptual framework that integrates several motivational theories, empirical studies, and neuroscience research is proposed to guide future studies of dynamic prioritization in multiple-goal contexts. Rooted in control theory, the proposed framework illustrates self-regulation processes in prioritizing tasks and explicitly shows important factors affecting the prioritization process so that empirical results can be integrated into the framework and future studies can be inferred. By illustrating information flow in the self-regulation processes and the brain structures associated with prioritization, the framework should help facilitate development of robust computational models of task prioritization.
Characterization of Changes in Electrophysiological Activity in an Operational Environment BIBAFull-Text 1177-1181
  Natalia Mazaeva; Santosh Mathan; Michael Dorneich; Stephen Whitlow; Patricia May Ververs
The purpose of this study is to characterize differences in EEG collected under stationary conditions and that collected in mobile settings. EEG activity has not been evaluated in operational settings due to difficulties associated with processing of EEG in real-world settings such as real-time removal of artifacts, operational environments, and possible differences in EEG frequency associated with mobility. Utilization of EEG measures of cognitive activity in dynamic environments demands the use of real-time algorithms of signal decontamination and characterization of specific components of EEG activity. In this study, EEG was collected and filtered in real-time in a set of controlled stationary scenarios and similar mobile scenarios in order to characterize differences in EEG power, electrode locations, and individual differences under mobility while participants performed tasks of variable difficulty. Results illustrate that the lack of systematic differences in EEG spectral power associated with mobility may point to feasibility of successful collection and analysis of EEG activity in such settings.

HUMAN PERFORMANCE: Novel Applications of Simulation Technology in the U.S. Army

Human Performance Modeling for Operational Command, Control and Communication BIBAFull-Text 1182-1185
  Jeffrey T. Hansberger; Diane Barnette
The challenges facing the military due to adversaries, new battlegrounds, and ever-changing technology requires innovative, fast, and efficient means to conduct and support research. The Army Research Laboratory has developed a modeling environment, C3TRACE (Command, Control, and Communication -- Techniques for Reliable Assessment of Concept Execution), that aids in the evaluation of different personnel architectures and information technology on system and human performance. This modeling environment, which was originally designed to address tactical command issues, has been applied to a higher level organizational command and control environment within the Joint Forces Command. Specifically, it was applied to an urban operations exercise to evaluate the effect of various personnel structures and communication means on awareness, flow of information, and decision-making.
The Use of Massive Multi-Player Gaming Technology for Military Training: A Preliminary Evaluation BIBAFull-Text 1186-1190
  Shawn A. Weil; Talib Hussain; Tad Brunye; Jason Sidman; Lisa Spahr
Publicly available Massive Multi-Player Games (MMPG) allow multiple individuals to work together in simulated situations. To meet complex game objectives, users must exhibit high degrees of coordination. This is similar to the types of interactions required for effective coordination in military team environments, and this resemblance has not gone unnoticed. DARWARS is an initiative that aims to support a diverse array of distributed simulation-based military instruction, including those that allow large numbers of participants to interact in on-line virtual worlds. In effect, MMPGs are being considered as platforms for future training. In this paper, we describe a framework and evaluate a preliminary methodology for training teamwork skills (e.g., information exchange, teammate monitoring) in an MMPG environment. Data collected from a field exercise of 40 infantry soldiers suggests that MMPGs are capable of training teamwork skills in distributed environments. Based on the results of this exercise, we provide practice-oriented guidelines for using MMPGs as a training tool, and offer some suggestions for future research into effective performance measurement paradigms in this environment.

HUMAN PERFORMANCE: Lessons Learned and the Future of Human Performance Modeling

Human Performance Modeling in the Army: A Long and Winding Road BIBAFull-Text 1191-1195
  Laurel Allender; Sue Archer; Troy Kelley; John Lockett
The history of human performance modeling (HPM) in the U.S. Army is described, the early influences and technological events that made it possible. Highlights of significant milestones are presented, including HPM efforts that were influential in influencing the U.S. Army's modeling practices and in changing system design. The latest challenges in cognitive modeling, advanced decision making, stressors, and the particular challenges of distributed and linked simulations are discussed as well as the prospect of using methods from neuroscience for validation of cognitive models.
Critical Features in Human Motion Simulation for Ergonomic Analysis BIBAFull-Text 1196-1199
  Matthew P. Reed; Don B. Chaffin; Julian Faraway
Digital human figure models (DHM) are increasingly the tools of choice for assessments of the physical ergonomics of products and workplaces. Software representations of users and workers are used to visualize people performing tasks of interest. Analyses have usually focused on clearance and reach in static postures, not because the actual tasks are static, but rather because DHM have lacked robust, accurate motion simulation capability. Research is underway at many institutions to develop improved motion simulation methods, drawing on a wide variety of methodologies from fields such as computer graphics, kinesiology, motor control, and robotics. Experience in the Human Motion Simulation Laboratory at the University of Michigan suggests that conventional metrics of accuracy for posture and movement prediction do not adequately capture the aspects of human movement that are most important for ergonomic analysis. This paper identifies and justifies a set of these critical features.
Time-Based Modeling of Human Performance BIBAFull-Text 1200-1204
  Esa M. Rantanen; Brian R. Levinthal
This paper presents a probabilistic approach to modeling human performance. Instead of focusing on mean performance, the effects of taskload on the distributions of performance variables are examined. From such data, probabilities of given levels of performance can be derived and methods of measurement that expand the analyses beyond those of the mean developed. Results from two experiments, one abstract, the other realistic, are presented in terms of timely performance on required tasks. As taskload increased, the participants were less likely to act on the experimental tasks at an earliest opportunity than under low taskload, resulting in increase of 'too late' errors. Measurement of taskload and performance in temporal terms also allowed for bracketing and making inferences about mental workload, which is not directly measurable.
Psychologically Plausible Cognitive Models for Simulating Interactive Human Behaviors BIBAFull-Text 1205-1209
  Michael L. Bernard; Patrick Xavier; Paul Wolfenbarger; Derek Hart; Russel Waymire; Mathew Glickman; Mark Gardner
The intent of Sandia National Laboratories' Human Interactions (HI) project is to demonstrate initial virtual human interaction modeling capability. To accomplish this, we have begun the process of simulating human behavior in a manner that produces life-like characteristics and movement, as well as creating the framework for models that are based on the most current experimental research in cognition, perception, physiology, and cognitive modeling. Currently the simulated human models can sense each other, react to each other, and move about in a simulated 3D environment. A preliminary action generation or motor-level cognition model, which transforms abstract actions generated by high-level cognition to actions that can be carried out by a simulated physical human model, has also been developed. Our work has yielded models of perceptual, spatial, and motor functioning and memory that will be embedded in upgrades to the cognitive framework.


A Platoon Level Model of Communication Flow and the Effects on Soldier Performance BIBAFull-Text 1210-1214
  Jennifer C. Swoboda; Patricia W. Kilduff; Joshua P. Katz
The Future Combat System (FCS) initiative is at the center of the Army's Future Force Vision. To predict how proposed systems and displays will impact situational understanding and, thereby, decision making, the U.S. Army Research Laboratory Human Research and Engineering Directorate (ARL HRED) used the tool, Command, Control, and Communication: Techniques for Reliable Assessment of Concept Execution (C3TRACE). C3TRACE is a modeling environment in which one can develop multiple concept configurations quickly and efficiently, minimizing the need for multiple human-in-the-loop experiments. Among the performance measures tracked are operator utilization, completed versus dropped messages, and the probability of making a "good" decision, that is, a decision supported by the required information. C3TRACE was used to develop a model of a Future Combat System (FCS) platoon equipment concept -- wrist-mounted displays for the dismounted positions and laptop-type displays for the mounted positions. This paper discusses the effects of display device communication processing on Soldier performance in mounted vs. dismounted positions.
A Method for Exploring Teamwork Modeling and Assessment Within a Multiplayer Game BIBAFull-Text 1215-1219
  Craig Haimson; David Diller; Laura Kusumoto
Massively multi-player games (MMPGs) have the potential to enable training at a level of participation, intensity, and fidelity previously unrealized. As a first step towards the implementation of automated performance measurement technology for MMPGs, we explored an approach to developing training and assessment of team performance during urban infantry operations simulated within the Asymmetric Warfare Team Training Technology (AW-VTT) under development by Forterra Systems and RDECOM-STTC. Our method entailed (1) mapping a theoretical framework to established Army doctrine, (2) mapping doctrinal descriptions to specific activities within a simple yet operationally-valid scenario, and (3) developing rule-based descriptions of these activities and formally representing them within finite state networks to validate their consistency and completeness. We then enacted the scenario within AW-VTT to demonstrate the environment's capability for simulating the behaviors required for assessment of teamwork in this scenario. We describe this approach and discuss lessons learned.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Are We Ready to Consider Individual Differences in Human Capabilities in Our Workplace Design?

Are We Ready to Consider Individual Differences in Human Capabilities in Our Workplace Design BIBFull-Text 1220-1223
  Krystyna Gielo-Perczak; Waldemar Karwowski; Peter A. Hancock; William S. Marras; Raja Parasuraman

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Human Performance

Being Optimistic May Not Always Be Advantageous: The Relationship Between Dispositional Optimism, Coping, and Performance BIBAFull-Text 1224-1228
  William S. Helton; Gerald Matthews; Joel S. Warm; William N. Dember
The effects of dispositional optimism on performance and self-reports of coping strategy were examined in a low and a high signal salience vigilance task performed in quiet or during exposure to jet-aircraft engine noise. The results of this study partially support Scheier and Carver's (1985; 1987) habitual coping styles theory, in which people varying in optimism differ in their general coping strategies. Optimism in most cases correlated positively with task-focused coping and negatively with off-task approaches. When the task setting elicited a coping style contrary to dispositional preference, however, performance was actually impaired. In the low-salience, quiet condition of this experiment optimism correlated negatively with performance; this condition also elicited elevated levels of maladaptive, off-task coping. Being highly optimistic may not always be an advantage in performance settings.
Is Peppermint An Ergogenic Aid to Athletic Performance BIBAFull-Text 1229-1233
  Cheryl M. MacKenzie; Alan Hedge
This study investigated the effects of a claimed ergogenic aid, peppermint odor inhalation, on running performance, under different experimenter-induced odor expectancy conditions. Eighteen fit, young women subjects performed 3 x 1/4-mile runs, under three randomly assigned treatments: peppermint-scented mask; unscented mask; and no mask. Each subject was also given either a positive, negative, or neutral expectancy information message regarding peppermint's influence on performance. Results showed that neither peppermint inhalation nor expectancy information had any significant effect on running time. However, expectancy information did slow the running times of high positive affect subjects. Subjects receiving negative information showed significantly slower heart rates during the running task.
Individual Difference Effects on Performance in a Complex, Multi-Decision-Making Environment BIBAFull-Text 1234-1237
  Elizabeth Pratt; R. James Holzworth
The present research examines the impact of cognitive style and short-term memory (STM) capacity on the computer interface usability of a pilot simulation. Participants screened for individual differences in cognitive style and STM capacity were randomly assigned to a training condition within the Multi-Attribute Task Battery (MAT; Arnegard & Comstock, 1991). Training conditions varied in automation settings (adaptive versus static). Participants transferred to a novel static condition. Between subjects independent variables were individual differences in STM capacity (high, low), cognitive style (analytic, holistic, quasi-rational), and training (static versus adaptive). Within subjects independent variables were training (four blocks) and transfer (four blocks) sessions. Dependent variables were accuracy and reaction time. Results suggest that individual differences in STM capacity and cognitive style are orthogonal constructs that interact to affect skill acquisition and strategy development for visual-spatial tasks. Implications related to computer interface design are discussed.
The Role of Individual Differences in Dynamic Team Performance BIBAFull-Text 1238-1242
  Randy Brou; Stephanie Doane; Gary Bradshaw; J. Martin Giesen; Mark Jodlowski
Teams often operate in dynamic task environments where the state of the world and the coordinative requirements for optimal performance change rapidly. To build effective teams, it is important to know what factors influence team performance. The present research investigates several factors that may influence team performance in dynamic environments. In this study, participants first completed a battery of cognitive and non-cognitive tests. Results of the tests were used to form three-person teams with varying levels of ability. Team performance was scored in 12 dynamic tasks. Individual differences in cognitive ability and personality characteristics were then used to predict team-level performance. Results indicate that two team member characteristics, cognitive ability and stress tolerance, are important to dynamic task performance, while other characteristics such as achievement motivation play roles in specific circumstances. Implications of these results are discussed.
Mobile Wireless Technology for Individuals with Cognitive Impairments: Device Analysis and Customization BIBAFull-Text 1243-1247
  Vicki Haberman; Michael L. Jones; James L. Mueller
A compensatory aid is being developed to support community re-entry for persons with cognitive impairments resulting from acquired brain injuries (ABI). With mobile wireless technology as a design platform, research in computer science and rehabilitation engineering is integrated with industrial design to explore the central concern: the design of a user interface that is understandable and operable by individuals with significant cognitive impairments. Much of what is learned during this project is applicable to enhancing the usability of mobile wireless technologies for users without disabilities.


Accidental Inversion During Three-Dimensional Orientational Control BIBAFull-Text 1248-1250
  Derek D. Diaz; Valerie K. Sims
This research investigates a type of operator error, referred to here as accidental inversion, which occurs during manipulation of the pitch and yaw of a real or simulated object in a three-dimensional environment. Specifically, we investigated whether accidental inversion is linked to a hypothetical individual difference variable referred to here as "axis-map" expectation. Participants exhibited two distinct types of axis-map expectations to the exact same visual stimuli -- matching and ambiguous. An important implication for person-machine systems is that one should expect naïve operators to already have a pre-conceived notion of how an interface for orientational control works and that different operators may have different, and possibly opposite, axis-map expectations.
Investigating Individual Differences and Instructional Efficiency in Computer-Based Training Environments BIBAFull-Text 1251-1255
  Sandro Scielzo; Haydee M. Cuevas; Stephen M. Fiore
This study assessed the extent to which a guided learner-generated questioning strategy could facilitate the acquisition of task-relevant knowledge and improve the instructional efficiency of a computer-based training program for a complex dynamic distributed decision-making task. This study also investigated how individual differences in verbal comprehension ability may interact with this instructional strategy to impact post-training outcomes. Overall, results highlighted the importance of learner aptitudes in complex task training and also showed that the effect of the instructional strategy on knowledge acquisition and the training program's instructional efficiency was strongest for learners with low verbal comprehension ability. Implications for the design of adaptive learning systems are discussed.
The Effects of Individual Differences in Working Memory on Multimedia Learning BIBAFull-Text 1256-1260
  Jennifer A. Batka; Scott A. Peterson
With the advance of instructional technologies, multimedia presentation formats have become increasingly common in business, military, and educational pursuits. Previous research has found that the use of certain multimedia design principles may alleviate demands on working memory and thus improve the learning process (Mayer, 2001). Our study examined the utility of three of these principles: the contiguity, redundancy and modality principles (Mayer & Moreno, 2003), in the design of a multimedia presentation explaining the formation of hail. Results indicated that use of the contiguity, redundancy, and modality principles tended to increase learning outcomes for individuals with low working memory capacities but decrease learning outcomes for those with higher working memory capacities. These findings call into question the generality of these design principles, and suggest that multimedia designers should carefully consider the effects of individual differences in the human learner.
Prevalence and Mediating Factors of Post-Traumatic Stress in Professional Fire-Fighters BIBAFull-Text 1261-1265
  Allison Watters; Kevin Hamilton; J. Patrick Neary; Gregory Anderson
Previous studies on Post-Traumatic Stress (PTS) in fire-fighters have typically examined group responses to unusual and traumatic events. In this study, symptoms of PTS were observed in a group of urban Canadian fire-fighters during routine operations in the context of typical daily work. Participants completed a PTS questionnaire as well as a workplace health questionnaire which assessed environmental and contextual factors in addition to personal health. Elevated levels of PTS were observed in 18.1° of the 105 fire-fighters studied. Those who reported elevated symptoms also reported more concern for financial issues, more worries and more concern about needing physical exercise and support services. These results indicate that emergency response professionals such as fire-fighters can develop elevated levels of PTS in the context of routine work. The findings also suggest that the development of PTS involves a complex relationship between characteristics of stressors, work related variables and other contextual factors specific to the individuals affected. Complex models are needed to account for these types of interactions, particularly in chronically stressful occupational settings. Strategies for mitigating symptoms of PTS are discussed and suggestions for future research are offered.
Developing and Anthropomorphic Tendencies Scale BIBAFull-Text 1266-1268
  Matthew G. Chin; Valerie K. Sims; Linda Upham Ellis; Ryan E. Yordon; Bryan R. Clark; Tatiana Ballion; Michael J. Dolezal; Randall Shumaker; Neal Finkelstein
A 208-item scale was developed to measure self-reported anthropomorphic tendencies during interactions with various non-human entities. The potential targets of anthropomorphism included technology-laden machines such as computers, other objects such as backpacks, living things such as houseplants, and abstract entities such as a god or higher power. Scale items assessed the degree to which participants agreed with statements regarding the perceived attributes of the entities, speech directed toward the entities and the treatment of the entities. A factor analysis suggested that the scale measures four independent types of anthropomorphism: "extreme" anthropomorphic tendencies, anthropomorphism of a god or higher power, anthropomorphism of pets, and "negative" anthropomorphism. Further analyses indicated that anthropomorphic tendencies were self-reported when pertaining to pets and a god or higher power. However, participants tended not to self-report inappropriate "negative" anthropomorphism toward computers, cars, microwaves, etc. These disparate findings appear to be due to social desirability of anthropomorphism.


Viscoelastic Responses of the Lumbar Spine During Prolonged Stooping BIBAFull-Text 1269-1273
  Gwanseob Shin; Gary A. Mirka; Elizabeth G. Loboa
There is considerable evidence that awkward postures of the low back are related to the incidence of low back disorders (LBDs), but the specific biomechanics/physiology of this link is not fully developed. This study combined empirical work with finite element analyses to explore this relationship. The empirical work focused on quantifying the time-dependent responses of the lumbar spine during a prolonged stooped posture by assessing the changes in the sagittal plane range of motion and the electromyographic activity of the back extensor musculature during and after prolonged stooping. Ten healthy participants performed a regimen of a 10 minute stooping period followed by a 10 minute upright standing recovery period, with an isokinetic lift at every 2.5 minutes. Results showed significant creep effects of the flexion angle and the increased activity of extensor muscles in stooping to compensate for the reduced extensor moment producing capability of the passive tissues. The 10 minute upright standing did not produce a full recovery of the lumbar spine tissues but a 30 second rest break in the middle of the stooping moderated these viscoelastic responses. A nonlinear viscoelastic 3D finite element (FE) model of the lumbar spine was developed to predict the responses of the passive and active tissues of the low back. Validation of the FE model by comparing its predicted results (range of motion, muscle activation levels, etc.) with experimental results indicated good agreement in terms of mechanical behaviors in stooping, confirming the capability of the FE model as a potential tool for risk assessment of the prolonged stooping tasks.
Cumulative Effects of Load Frequency and Velocity on the Lumbar Spine Response During a Repetitive Lifting Task BIBAFull-Text 1274-1277
  Naira H. Campbell-Kyureghyan; William S. Marras
Work-related low back disorders arise from a complex interaction of events. One aspect of interest is cyclic or repetitive tasks, which are performed on a daily basis in a variety of situations, and often for extended periods of time. The specific questions to be addressed in this study are the effects of the load frequency and time-dependent material properties on the lumbar spine component behavior. The newly developed and validated, subject specific, finite element model of lumbar spine is used in conjunction with kinematic data imported from human subjects experimental testing of repetitive sagittally-symmetric lifting and lowering tasks. Creep and energy dissipation in the lumbar spine components are used to quantify the effect of lifting frequency and velocity on the potential for injury over an eight-hour workday.
Bone mineral content and fatigue failure of lumbar motion segments in simulated flexed lifting: Does specimen age influence the relationship BIBAFull-Text 1278-1282
  Sean Gallagher; William S. Marras; Alan S. Litsky; Deborah Burr
This paper describes a comparison of the fatigue failure responses of older versus younger lumbar spine cadaver motion segment specimens. These specimens were repeatedly subjected to loads simulating those experienced by the spine in lifting a 9 kg load in different torso flexion postures (0, 22.5, and 45 degrees of flexion). An older sample of 36 motion segments (average age 81 years + 8 SD) is compared with a younger sample of 18 motion segments (average age: 47 years + 9 SD) with respect to the number of cycles to failure and results of survival analyses evaluating the effects of flexion and bone mineral content with and without the younger data set. Compared to the older sample of spines, the younger sample exhibited many more cycles to fatigue failure in all the torso flexion conditions (10020 versus 8267 average cycles to failure in 0 degrees flexion, 7124 versus 3262 in 22.5 degrees flexion, and 3229 versus 263 cycles to failure in 45 degrees flexion). The increased cycles to failure in young specimens is likely due to the increased bone mineral content (BMC) in younger motion segments (30.7 g + 11.1 g per motion segment versus 27.8 + 9.4 g). Cox regression analyses modeling both flexion effects and BMC indicate that betas are similar when just older spines are modeled and when younger specimens are included in the analysis. Betas for survival analysis models with and without younger specimens generally show little change for flexion (2.716 versus 2.756 for 22.5 degrees [0 degrees referent], 3.926 versus 3.380 for 45 degrees [0 degrees referent]). Bone mineral content shows a similar protective effect in both models (Betas: -0.127 versus -0.087). Overall, comparison of the models indicate that risk ratios are similar for 22.5 degrees flexion, slightly increased for 45 degrees flexion and slightly more protective influence predicted for BMC in the combined sample versus the older sample alone.
Recurrence of Occupational Low Back Disorders: The Influence of the Definition of Recurrence BIBAFull-Text 1283-1286
  Sue A. Ferguson; William S. Marras; Deborah L. Burr
Recurrent low back disorder rates vary from as low as 1% to as high as 82%. The sample population as well as definition of recurrence influence the rate of recurrence found in the literature. The objective of this study was to examine four definitions of recurrent low back disorders on the same population. Two hundred and six workers with manual material handling jobs who had reported work-related low back pain were monitored prospectively for recurrent low back disorders for 1-year. Recurrence of low back disorder was defined as 1) low back pain symptoms, 2) a visit to a medical provider (company or personal) for low back pain, 3) self-reported time off work due to low back pain, and 4) confirmed (by employer) lost time due to back pain. The recurrence rates were 58% for pain symptoms, 36% for seeking medical attention, 15% for lost time and 10% for confirmed lost time.
Comparison of Biomechanical and Anatomical Effects Following Eccentric and Concentric Exertions BIBAFull-Text 1287-1291
  Amrish O. Chourasia; Mary E. Sesto; Youngkyoo Jung; Robert S. Howery; Robert G. Radwin
Work place exertions may include muscle shortening (concentric) or muscle lengthening (eccentric) contractions. This study investigates the upper limb mechanical properties and magnetic resonance images (MRI) of the involved muscles following submaximal eccentric and concentric exertions. Twelve participants were randomly assigned to perform at 30° per second eccentric or concentric forearm supination exertions at 50% isometric maximum voluntary contraction (MVC) for 30 minutes. Measurement of mechanical stiffness, isometric MVC, localized discomfort and MRI supinator: extensor signal intensity ratio was done before, immediately after, 1 hour after and 24 hours after the bout of exercise. A 53% average decrease in mechanical stiffness after 1 hour was observed for the eccentric group (p< 0.05) compared to a 1% average decrease for the concentric group (p> 0.05). Edema, indicative of swelling, was observed 24 hrs after exercise, with an average increase in the MRI supinator: extensor signal intensity ratio of 36% for the eccentric group and less than 10% for the concentric group (p<0.05).

INDUSTRIAL ERGONOMICS: Slips, Trips, and Falls

Validity of Functional Stability Limits as a Measure of Balance in Adults Ages 2373 BIBAFull-Text 1292-1296
  Kyle McDermott; Cory Shaw; Jason Demchak; Mary Ann Holbein-Jenny
Functional stability limits have been proposed as a psychometric indicator of balance ability that could be used to incorporate stability constraints into ergonomic task analyses. Decreased functional stability limits are assumed to indicate decreased balance ability. These stability limits have been quantified for a young adult population. However, their validity as a measure of balance ability has not been investigated. The purpose of this study was to investigate the construct validity of functional stability limits as a measure of balance ability by quantifying the relationship between these stability limits and age and other more common measures of stability. As hypothesized, functional stability limits decreased with age, were positively related to performance on the Multi-Directional Reach Test, a valid indicator of fall risk for the elderly, and were negatively related to postural sway. However, the strength of these relationships was only moderate; continued analysis is exploring possible explanations for these results.
Biomechanics of a Micro-Slip BIBAFull-Text 1297-1301
  Angela DiDomenico; Raymond W. McGorry; Chien-Chi Chang
A study was conducted to investigate the differences in common biomechanical measures for slips not leading to falls, particularly micro-slips (heel displacement less than 30 mm). Thirty-one participants ranging in age from 18-67 years old performed walking trials at three gait speeds over three floor surfaces with substantially different coefficients of friction. The magnitude of heel displacement was significantly affected by floor surface and gait velocity. Trials were categorized by heel displacement (non-slip, micro-slip, slide) and then biomechanical measures were calculated. Findings of the present study indicated that biomechanical measures differed significantly for all three of the slip categories. Although micro-slips are not generally perceived by the individual, biomechanically they differ from normal walking and should be investigated further to understand the conditions that cause a fall to occur after a slip.
Aging Effect on Joint Moment Generation Strategy in Successful Reactive-Recovery from Unexpected Slips BIBAFull-Text 1302-1305
  Jian Liu
3D joint moment analysis has been regarded as a valuable tool in slips and falls studies. In addition to the commonly used peak joint moments, joint moment distribution characteristics enabled by 3D approach may reflect the relative importance of different anatomical planes. The objective of this study was to examine the aging effect on lower extremity joint moment distribution characteristics among all the three anatomical planes during the process of successful reactive-recovery from unexpected slips. Nine young and nine old participants who were identified as having successful recovery trials were selected from previously conducted walking experiments. Unexpected slips were created by introducing slippery floor surface without participants' awareness. Peak joint moment ratio (JMP Ratio) was defined and computed for each anatomical plane. Results indicated significant decreased sagittal JMP Ratio for the old group and significant increased sagittal JMP Ratio for the young group during recovery. It was concluded that young and old individuals appeared to adopt different joint moment distribution strategies, which may be due to age-related lower extremity strength degradation.
Effect of Localized Muscle Fatigue Induced at Different Joints on Postural Control BIBAFull-Text 1306-1310
  Navrag B. Singh; Maury A. Nussbaum; Dingding Lin; Michael L. Madigan
Localized muscle fatigue has been demonstrated to compromise postural control, yet potential differential effects of the site of fatigue have not been determined. In this study, the effects of short-term induced fatigue in four muscle groups (shoulder, torso, knee, and ankle) on standing sway were determined. Sixteen young participants were required to perform fatiguing sub-maximal isotonic exercises. Postural sway was recorded using a force plate before and after the exercises. Fatigue induced at the ankle and torso was found to have largest adverse effects on postural control. These results have implications for the control of fatigue-related falls and the design of future experiments.
Experience on an Elevated Inclined Surface and Postural Control BIBAFull-Text 1311-1314
  Chip Wade; Jerry Davis
Historically, roofing work has been ranked among the highest of all industries with incidents of fatal and non-fatal falls. The purpose of this study was to investigate the exposure to an elevated inclined surface on postural stability. Twenty males, 10 experienced roofers, and 10 inexperienced college students participated in this study, which consisted of a preliminary balance test, followed by exposure to an elevated inclined surface for ten-minutes of exposure. While subjects walked, a motion analysis system recorded their position on the elevated roofing surface to determine the amount of time a subject spent in each of two areas, central or peripheral. Results suggest that both experienced and inexperienced individuals demonstrated decreased postural stability following exposure to the elevated inclined surface, with experienced individuals demonstrating a lesser decrement. Furthermore, experienced individuals spent a significantly greater portion of time in the peripheral area (extremities of the elevated roofing surface) surface compared to inexperienced individuals. These findings suggest that there is a significant decrement in postural stability due to exposure to an elevated inclined support surface.


The Effects of Fatigue from Repeated Trunk Extensions on Trunk Muscle Activity BIBAFull-Text 1315-1319
  Dan Kelaher; Gary Mirka; Carolyn Sommerich
Asymmetric trunk postures and trunk dynamics have been implicated as risk factors for occupational low back disorders. Muscle fatigue has also been cited as an ergonomic issue, though not directly linked to an increased risk of low back injury. This paper investigates the effect of trunk extensor muscle fatigue on muscle activity levels during symmetric and asymmetric trunk extension exertions. The results show that muscle fatigue alters both flexor and extensor muscle activity patterns in asymmetric trunk extensions earlier than in sagittally-symmetric trunk extensions. This quickened fatigue response to asymmetric trunk motions could be a contributor to the increased risk of low back injury seen in occupational tasks that include asymmetric trunk lifting.
Comparison of Spinal Loads in Kneeling and Standing Postures During Manual Materials Handling BIBAFull-Text 1320-1324
  Gang Yang; Riley Splittstoesser; Gregory Knapik; David Trippany; Sahika Vatan Korkmaz; Jeffry Hoyle; Parul Lahoti; Steven Lavender; Caroline Sommerich; William Marras
Kneeling in a restricted posture during manual materials handling has been associated with increased risk of low back pain. Little is known about the effect of kneeling posture on spinal loads. The purpose of this study was to compare differences in spinal loading between kneeling and standing postures for lifting tasks. Twelve subjects asymmetrically lifted luggage of three weights to three heights from floor while kneeling. Three subjects also performed the same tasks from waist height while standing. An adapted free-dynamic EMG-assisted biomechanical model was used to calculate spinal loads. Statistical analysis showed that there was no difference in compression between kneeling and standing (p=0.9605), but kneeling resulted in increased anterior-posterior and lateral shear forces on the lumbar spine (p =0.0002 and p<0.0001, respectively). Spinal loading changes while kneeling in a restricted posture may increase the risk of low back injury and must be considered in ergonomic job design.
Lifting Performed on Laterally Slanted Ground Surfaces BIBAFull-Text 1325-1329
  Zongliang Jiang; Gwanseob Shin; Jacklyn Freeman; Stephanie Reid Reid; Gary A. Mirka
Many outdoor work environments (e.g. agriculture and construction) require manual material handling activities on variable grade ground surfaces. Quantifying biomechanical responses for lifting under these conditions may provide insight into the etiology of lifting-related injuries. The aim of the current study was to quantify the effect of laterally slanted ground surfaces on biomechanical responses. Ten subjects performed lifting exertions (using a 40% of max load) while standing on a platform that was laterally tilted at 0, 10, 20 and 30 degrees from horizontal. During the lifting tasks the whole body kinematics were collected, which were later used in a dynamic biomechanical model to calculate the time-dependent moment about L5/S1 and the time-dependent lateral forces acting on the body segments. The results showed a consistent reduction in the peak dynamic L5/S1 moment (decreased by 9%) and an increase in the lateral forces (increased by 111%) with increasing slant angle.
Co-Contraction Recruitment and Spinal Load During Isometric Pushing Tasks BIBAFull-Text 1330-1333
  Kevin Granata; Patrick Lee; Tim Franklin
Pushing and pulling tasks account for 20% of occupational low-back injury claims but few studies have investigated the neuromuscular control of the spine during these tasks. Primary torso muscle groups recruited during pushing tasks include the rectus abdominis and external obliques. However, theoretical analyses suggest that co-contraction of the paraspinal muscles is necessary to stabilize the spine during flexion exertions. A biomechanical model was implemented to estimate co-contraction and spinal load from measured surface EMG and trunk moment data recorded during trunk flexion and extension exertions. Results demonstrate that co-ontraction during flexion exertions was approximately twice the value of co-ontraction during extension. Co-ontraction accounted for up to 47%total spinal load during flexion exertions and spinal load attributed to co-contraction was nearly 50% greater during flexion than during extension exertions despite similar levels of trunk moment. Results underscore the need to consider neuromuscular recruitment when evaluating biomechanical risks.
Neuromuscular Control and Active Trunk Stiffness during Isometric Flexion and Extension BIBAFull-Text 1334-1338
  Kevin Granata; Patrick Lee
Pushing and pulling tasks account for 20% of low-back injury claims. Torso flexion necessary for pushing exertions requires different muscle recruitment than for extension exertions typical of lifting tasks. These differences in recruitment and control may influence spinal stability and associated risk of injury. Active muscle stiffness is considered the primary stabilizing mechanism for spinal stability. Therefore, active trunk stiffness was recorded while subjects generated upright isometric trunk flexion and extension exertions against an isotonic preload. Small pseudo-random force disturbances were superimposed on the preloads causing small amplitude trunk movements. Trunk stiffness was computed from systems identification of the measured force and trunk motion data. Results demonstrated significantly greater stiffness during flexion exertions as compared to extension exertions. EMG data suggest this difference was due to increased co-contraction during the flexion exertions. These behaviours were attributed to the need to augment neuromuscular control of spinal stability during pushing tasks.

INDUSTRIAL ERGONOMICS: The History and Future of Ergonomics in Controlling Low Back Disorders

The Role of Ergonomics in Reducing Low Back Pain and Disability in the Workplace BIBAFull-Text 1339-1343
  Stover H. Snook
Low back pain is a common problem, an expensive problem, and a recurring problem. In this paper, the problem is defined, the available evidence is reviewed, and three types of interventions are discussed. The interventions are job design, changing personal behavior and beliefs, and secondary intervention to reduce the disability. Ergonomics plays an important role in each of the interventions. Although low back pain cannot be completely prevented, the evidence indicates that it can be reduced and managed with considerable success.
A Biomechanical Basis for Low Back Injury Risk in High Exertion Tasks BIBAFull-Text 1344-1348
  Don B. Chaffin
Manual work is still very prevalent in many jobs today. This paper will explore the historic role that biomechanics has played in understanding these outcomes, as well as reviewing various prevention strategies used today.
   The focus of the presentation will be on occupational low back pain. The discussion begins with the fundamental biomechanical reality; that the lumbar spine is often subjected to extremely large compression forces when one stoops to pick up an object, even if the object is of moderate weight. The paper will discuss this outcome, as well as biomechanics research in the late 80s that lead to inclusion in 1994 of a torso twisting risk factor in the "NIOSH Lifting Guideline."
   The growing use of mechanical aids (hoists, articulated arms and conveyors) has done a great deal to alleviate high levels of low back stress while lifting, but too often these same devices require people to twist and push and pull objects. High torso muscle antagonistic actions and vertebral shear forces were being predicted in such activities, especially when fast motions were involved. Concern also over shoulder injuries was growing related to the use of these devices, leading to the need to develop and use models of whole body exertions in industry to understand the full complexity of the problems for various groups of people.
   Recently some biomechanics research began to focus on another aspect of vertebral column function that makes it vulnerable to injury, particularly during fast motions with light loads. This vulnerability is due to the column's reliance on well coordinated torso muscle contractions to control its inherent dynamic instability.

INDUSTRIAL ERGONOMICS: Intervention Effectiveness

Effects of Rebar Tying Machine on Trunk Flexion and Productivity BIBAFull-Text 1349-1353
  Peter Vi
A before-and-after experimental design was conducted to evaluate the potential reduction in the risk of musculoskeletal injuries to concrete reinforcement workers when using an automatic rebar tying machine. Eleven (11) concrete reinforcement workers participated in this experiment. All dependent variables (trunk posture, and rebar tying time) were measured before and after implementing the rebar tying machine. The results of the study indicated that working with a rebar tying machine significantly reduced the magnitude and duration of exposure to awkward trunk posture. Tying time was reduced when participants used the machine. Based on trunk posture exposure and rebar tying time, it is concluded that the rebar tying machine can be an effective tool to reduce the frequency and duration of severe trunk flexion and increase productivity among concrete reinforcement workers.
Ergonomic Field Assessment of Bucking Bars During Riveting Tasks BIBAFull-Text 1354-1358
  Michael J. Jorgensen; Muthukurappan Viswanathan
Riveting tasks in aircraft manufacturing results in exposure to vibration from both rivet guns and bucking bars. Long term exposure to vibration has been associated with symptoms of vibration white finger and musculoskeletal disorders. Four different bucking bars of the same shape but different material and mass characteristics (90% tungsten, >90% tungsten, cold rolled and stainless steel) were investigated for vibration and grip muscle activity during a riveting task. The >90% and 90% tungsten bars (3.4 m/s2 and 3.6 m/s2, respectively) resulted in significantly less mean resultant weighted acceleration when compared to the cold rolled and stainless steel (5.3 m/s2 and 5.6 m/s2, respectively), whereas there was no difference in mean hand grip flexor or extensor muscle activity. These results suggest that for bucking tasks that allow access for the bucking bar size investigated, use of heavier but same sized tungsten bucking bars can reduce vibration transmission to the hand.
Evaluation of Microsoft's Comfort Curve Keyboard BIBAFull-Text 1359-1363
  Hugh McLoone; Chau Hegg; Peter W. Johnson
The purpose of this study was to determine whether there were any postural, performance or perceived comfort differences between a conventional straight keyboard and a new ergonomic concept keyboard developed by Microsoft called the Comfort Curve. The concept keyboard was designed to promote more neutral postures in the wrist using a built-in, padded wrist rest to reduce wrist extension and curved keys in alphanumeric section of the keyboard to reduce ulnar deviation. Using a repeated measures design, 26 typists from various occupations randomly used each keyboard for a period of 15 minutes. Wrist postures were measured using electrogoniometers, typing speed and accuracy was measured using typing performance software and discomfort was subjectively measured in the hands, forearms and shoulders and neck. Compared to the conventional straight keyboard, the Comfort Curve keyboard reduced ulnar deviation by 2.2° (p < 0.01) and wrist extension by 6.5° (p <0.01). There was a small differences in typing speed (50.6 vs 51.8 WPM; p = 0.03) but no differences in accuracy (93.1% vs. 93.5%, p = 0.29) between the Comfort Curve and standard keyboards respectively. Subjective discomfort ratings in all measured body locations were lower with the Comfort Curve keyboard. The results indicate that the concept keyboard achieved its design goal of reducing wrist extension, ulnar deviation and discomfort while not compromising typing speed and accuracy.
Electromyographic Evaluation of a New Approach to Descending Stairs While Carrying A Stretcher BIBAFull-Text 1364
  Steven A. Lavender; Karen M. Conrad; Paul Reichelt; Aniruddha Kohok; Jessica Gacki-Smith
One of the frequently encountered strenuous tasks performed by firefighter/paramedics (FFPs) is carrying a victim down the stairs on a stretcher. This study was designed to biomechanically evaluate new equipment that allows the stretcher to essentially be rolled down the stairs. The device called the Decent Control System looks like a pair of "tank treads" with a friction brake that span multiple steps was developed for this purpose (figure 1). We recruited 11 two-person teams of professional firefighters to test this approach. Electromyographic (EMG) data were obtained from each person as they carried and rolled the stretcher down a flight of stairs. Of the 8 muscles sampled from each firefighter, 4 muscles, including the left and right Erector Spinae showed significant reductions with the new approach. On average the 90th percentile normalized activity level for the Leader's (the FFP descending the stairs backwards) Erector Spinae decreased by 27% while the follower decreased 37%. The mean activity levels across the sampling period for these same muscle groups also decreased by a similar amount. In summary the Decent Control System reduced the activity in two of the primary low back muscles used when lifting. Such reductions, if experienced in the field, lessen the biomechanical loads transmitted to the spine and the potential for muscle over-exertion injuries.
Implementation of ergonomic interventions in healthcare: results from 111 facilities BIBAFull-Text 1365-1369
  Christopher A. Hamrick; Kaori Fujishiro; Jean Weaver; William S. Marras; Catherine A. Heaney
Work-related injuries in healthcare facilities are highly prevalent. This study examines the effectiveness of ergonomic interventions in 111 healthcare facilities on reducing musculoskeletal disorders (MSDs). Data from OSHA logs were collected prior to (baseline) and after implementing (follow-up) engineering controls. The average length of the baseline period was 445 days, and the average length of follow-up was 629 days. Overall, 83 work units (64%) experienced a decrease in the MSD rates during the follow%up period (z = -5.193, p< .001). The median rate ratio for all interventions was .63; that is, the intervention is associated with overall 37% decrease in MSD rates. The decrease in back injury rates observed in the study (44%) was much higher than the decline in the national data (17%). This study demonstrates that ergonomic interventions in healthcare facilities can result in decreased MSD rates.


Task-Based Measurement of Force in Automotive Assembly Using Worker Self-Assessment, Observational Analysis and Electromyography BIBAFull-Text 1370-1374
  Marissa L. Ebersole; Michael H. Lau; Thomas J. Armstrong
Worker self-assessments of force and observational assessments are convenient and efficient ways of assessing force demands. Past studies have criticized the accuracy and reliability of these methods of assessment. This study related worker perceptions of peak hand force, observational ratings of peak hand force and peak finger flexor and extensor EMG to understand the reliability and accuracy of these subjective methods when used at a subtask level. Worker and observer ratings of force had moderate correlation (R2 = 0.49). While the correlation of these subjective ratings to peak subtask EMG values was poor at an aggregate level, the percent agreement showed that workers and observers were within 1 point on a 10-point scale at least 61% of the time. This suggests that certain types of tasks were more suited to comparisons with the finger flexor and extensor EMG than others, and further investigation of these relationships is required.
An Observational Tool to Assess Work Organizational Factors BIBAFull-Text 1375-1379
  Ninica L. Howard
In a large 5-year prospective study of work-related upper extremity musculoskeletal disorders (UEMSDs), conducted by the SHARP Program in Washington State, an observational tool was used to assess the organization of work in twelve worksites in the health care and manufacturing industries. The tool, a two page checklist, assessed the physical, social and temporal aspects of the work, and the global and task level job content. A comparison between industry sectors found variability. Significant associations between industry sector and both structural restraints of the task activities (p<0.0001) and pacing determinant (p<0.0001) were found. Several work organizational factors were negatively correlated including labor skill level and pacing determinant (-0.51, p<0.0001). Other work organization factors were positively correlated such as social content and pacing determinant (0.62, p<0.0001). These data will be used to investigate the relationships between physical, psychosocial, work organizational and individual factors and the risk of UEMSDs.
Repeatability of an Exposure Assessment Method for Job Rotation BIBAFull-Text 1380-1384
  Susan Kotowski; Kermit Davis; Michael Jorgensen
As job rotation has become a widely used intervention strategy for the prevention of a wide variety of musculoskeletal disorders, there is a need for the development of assessment techniques that take into account the complexities of multiple body region stressors. The current study investigates the repeatability of a video-based analysis method that combines the exposure measure of four body regions: neck, shoulder, low back, and hand/wrist. Twelve analysts completed the assessment twice for 15 different job rotation schemes. The repeatability was found to be strong (ICC > 0.53) in many of the body regions when individual jobs were evaluated with minimal decrease in repeatability when the entire rotation scheme was considered. Overall, the video-based method provides a potential quick and easy method that will allow for the versatile evaluation needed for practitioners when quantifying exposure for job rotation schemes.
Exposure Assessment of Musculoskeletal Disorder Risk Factors in Hospital Work: Inter-Rater Reliability of Path Observations BIBAFull-Text 1385-1389
  Jungkeun Park; Jon Boyer; Jamie Tessler; Gustavo Perez; Laura Punnett
We examined the inter-rater reliability (IRR) of expert observations of ergonomic risk factors by four analysts. Ten jobs were observed at a hospital using a revision of the PATH method (Buchholz 1996). Two of four raters simultaneously observed each worker onsite. A total of 18 categorical exposure items were available for analysis. For most of the items, kappa coefficients were 0.4 or higher, showing that the IRR of the revised method was good. As predicted, agreement among observers was higher for the jobs with less rapid hand activity and for the analysts with more ergonomics and job analysis experience. The results show that the revised method can be reliably applicable to hospital work, and suggest that it can reasonably assess ergonomic exposure in any type of non-routine job across industries including healthcare industry.


Time Pressure and Mental Workload Effects on Perceived Workload and Key Strike Force During Typing BIBAFull-Text 1390-1394
  Laura E. Hughes; Kari Babski-Reeves
Although physical factors are accepted as risks in the development of work related musculoskeletal disorders (WMSDs), psychosocial factors may explain some of the remaining differences in susceptibility to WMSDs. The following study examined the effects of two psychosocial factors, mental workload and time pressure, on typing performance, perceived workload, and key strike force while typing. The majority of the key strike force measures increased with increases in time pressure and mental workload. Perceived overall workload (as measured using SWAT) increased with mental workload and time pressure, and typing performance decreased. Additionally, gender, locus of control, and perceived stress level did not influence outcomes. Physical risk factors may be mediated by psychosocial factors to increase risk for WMSD development in the upper extremities. Therefore, both physical and psychosocial aspects of work environments should be considered when designing jobs and work tasks to prevent injuries and improve productivity.
Assessing Palmar and Pinch Forces in a Manufacturing Plant Using a Dynamic Pressure System BIBAFull-Text 1395-1398
  Karin N. Barsness; Nathan J. Anderson; Paul E. Cassidy; Holly S. Wick
For work tasks requiring hand force and repetitive motions, risk increases directly proportional to an increase in force and repetition. Data on hand force exertion is generally collected by estimation of these forces by using subjective measurements, EMG recordings, or strain gauges. The objective of this study was to evaluate the use of a pressure pad system to quantify the ergonomic risk of a repetitive forceful manufacturing task. Effects of palmar and pinch forces and pressures associated with the current and proposed new work tasks were investigated by using a Novel Pliance dynamic pressure analysis system. Use of this system allowed the researchers to validate the reduction in forces associated with the tasks. This methodology has profound implications in that no compromise between internal and external validity is necessary, and allows quantification of ergonomic issues around forces, including tasks which requiring repetition and force exertions.
Arm Posture and Muscular Activity While Inserting and Aiming with Laparoscopic Tools BIBAFull-Text 1399-1403
  A. E. Trejo; M.-C. Jung; M. S. Hallbeck
Two laparoscopic tools, a scissor-type grasper and an ergonomically designed grasper, were compared in terms of arm posture and muscle activity during insertion into a trocar and during a standardized aiming task. Participants were asked to insert a laparoscopic tool into a simulated abdomen and hit five cross-shaped targets using their dominant hand; similar to reaching an organ during laparoscopic surgery. Twenty-six right-handed novice participants volunteered for the study. Two electrogoniometers were used to measure wrist flexion/extension, wrist deviation, and elbow flexion/extension angles. Six surface electrodes were used to measure%MVE of wrist flexors, wrist extensors, biceps brachii, triceps brachii, deltoid, and upper trapezius. The conditions used were five target positions, two touch screen monitor angles, and five hand postures. The scissors-type tool caused the largest wrist flexion, but the smallest %MVE from the wrist flexors. The method of gripping the tools was the most important factor determining joint angles and muscular load during the insertion and aiming tasks.
There Must be an Easier Way to Get the Paramedics Victim From a Bed to the Stretcher BIBAFull-Text 1404
  Steven A. Lavender; Karen M. Conrad; Paul Reichelt; Jessica Gacki-Smith; Aniruddha Kohok
Previous findings, based on interviewing and surveying firefighter/paramedics (FFPs), indicated that lateral transfers are strenuous and frequently performed (Conrad 2000). This research was aimed at biomechanically evaluating ergonomic interventions hypothesized to reduce the muscle use and loads placed on the spine during lateral transfers of victims between a bed and a stretcher. Specifically, this study tested the following hypotheses: 1) The use of folding rod(s) to facilitate grasping of the draw sheet and would reduce the amount of lifting required to actually move the patient, thereby reducing the dynamic load and the muscle recruitment. 2) The use of a polyethylene bridgeboard between the bed and the stretcher would facilitate sliding, thereby reducing the amount the victim actually had to be lifted. Eleven 2-person teams participated in a study in which a 75 kg dummy was laterally transferred from a bed to a stretcher using 2 rods, no rods, or 1 rod (both FFPs on the same side of the stretcher) with and without a bridgeboard. The FFPs were instrumented with surface electrodes over the left and right Latissimus Dorsi, Erector Spinae, External Oblique, and Rectus Abdominus. The 90th percentile normalized EMG values were analyzed for each condition. The results showed that the use of two folding rods, one on each side of the patient, did not significantly change muscle activity levels. The use of one rod significantly reduced Erector Spinae Activity and increased Latissimus Dorsi activity. The use of the bridgeboard significantly reduced the Erector Spinae Activity by 26 percent for the FFP on the cotside and be 16 percent for the FFP on the bedside. A significant interaction for the Erector Spinae muscles between the bridgeboard and the rod interventions suggests that FFPs could use either the single rod or the bridgeboard to minimize Erector Spinae recruitment when performing lateral transfers. In conclusion, the bridgeboard or the use of a single rod should be considered as potential interventions for the bed to cot lateral transfer tasks. Moreover, these results suggest that interventions may prove beneficial for other health care workers performing similar tasks, although the effectiveness should be validated with further studies.
Prediction of 2-D Lift Motions Using Artificial Neural Networks: An Evolutionary Approach BIBAFull-Text 1405-1409
  Miguel A. Perez; Maury A. Nussbaum
Movement prediction is an important aspect of human simulation, where more efficient and accurate models are needed. Artificial neural networks could potentially serve as a modeling option in this realm. This investigation evaluates the performance of a particular artificial neural network structure in modeling sagittally symmetric two-dimensional lifting and lowering movements. Model performance was evaluated using three training datasets, each consisting of distinct representation levels of the overall dataset. Results are discussed in terms of their practical meaning, and suggestions for future improvements in the modeling scheme are provided. Overall, artificial neural networks show promise as a modeling paradigm for the prediction of human movement.


Effect of User Experience on Powered Nutrunner Torque Reactions BIBAFull-Text 1410-1414
  Jia-Hua Lin; Raymond W. McGorry; Chien-Chi Chang; Patrick G. Dempsey
Powered tools are widely used in industries and they produce reaction forces that may be associated with upper extremity musculoskeletal disorders. The handle displacement, grip force, and upper limb EMG during impulsive torque reactions due to the effect of operator experience was examined in the study with 15 experienced and 15 novice tool users. The results show that experienced users allowed an average of 7.9° of handle displacement, while novice users allowed 11.5° when pistol grip tools were used on a horizontal surface. Experienced users exerted more grip force than novice users when using right angle tools, but less when using pistol grip tools. Average EMG magnitudes at flexors, extensors, and biceps were greater for experienced users. Recommendations regarding tool selection and workstation design can be derived from the results to minimize physical exposure for both user groups during power tool usage.
Development of a Multi-Joint Postural Exposure Assessment Tool for Job Rotation BIBAFull-Text 1415-1419
  Kermit Davis; Susan Kotowski; Michael Jorgensen
With practitioners more often adopting job rotation practices in their facilities, there is an increased necessity for effective methods to measure the complex exposures in the diverse jobs that may be selected for a particular job rotation scheme. Potential methods need to be both versatile and simple, ensuring easy application and low cost. The current study developed and evaluated the potential of a video-based analysis method that combines the exposure measure of four body regions: neck, shoulder, low back, and hand/wrist. Three experienced analysts assessed the postural load for all jobs within fifteen different job rotation schemes at a manufacturing facility. Several potential indices were developed, computed and discussed. Overall, the video-based analyses evaluated in the current study provide an easy and cost effective method that allows a practitioner to compare multiple stressors at one time. Future work will evaluate the effectiveness of the method in actually controlling musculoskeletal disorders as well as incorporate other risk factor exposures such as forces, repetition and motion.
Integrating Decision Support Systems and Ergonomics: A Case Study of Software Designed for Evaluating and Controlling Ergonomic Stresses BIBAFull-Text 1420-1423
  Sarah K. Womack; Thomas J. Armstrong
The study examines the use of a computerized decision support system developed for evaluating and controlling ergonomic stresses in an automobile assembly plant. The decision support system is based on a database of job videos, standardized work information, upper-extremity physical stress ratings for over 400 jobs, and historical job data that could be used in the job evaluation and improvement process. The study showed the software was useful to the extent that it had a user-friendly design, provided a significant amount of job information in one centralized location, and facilitated a more detailed analysis during injury investigation.

INTERNET: Internet

Can Experience Overcome Prior Knowledge's Impact on Web Navigation BIBAFull-Text 1424-1428
  Keith S. Jones; J. Shawn Farris; Brian R. Johnson
Farris (2003) discovered that users had greater difficulty finding information on a Web site when their prior knowledge was inconsistent with the site's content, relative to when their knowledge was consistent with it. In addition, he found that this difficulty was persistent over trials. To explain this persistence, Farris offered a schema-based account, which instantiated inconsistency in a single manner. The present study tested a prediction that was derived from Farris' account. The results associated with navigation efficiency supported Farris' account. The results associated with the choices made by participants as they navigated the site, however, contradicted his explanation. A new account, based on production-rules rather than schemata, is offered that accounts for both sets of results because it instantiates inconsistency in more than one manner. This new account has implications for the design and redesign of Web sites.
An Empirical Study of Paid Listings in Product Search and Purchase BIBAFull-Text 1429-1433
  Marc L. Resnick; Bernard J. Jansen
Pay-for-placement search has been described contradictorily as either the future business model of information retrieval on the Internet or as a deceptive nuisance for unsuspecting Web surfers. This study investigated user interaction with paid search listings during a set of naturalistic product search and purchase tasks. The study compared objective measures of how often these listings are used and subjective user opinions both during and after the task. Participants were more likely to view and select organic listings than paid listings. They also rated the organic results as more relevant for the shopping tasks and expressed suspicion of the paid listings. However, some users did use the paid listings and when the content was relevant there was no difference in the relevance ratings of the content pages themselves. A lack of neutral ratings for paid listings suggests that users will respond either negatively or positively to the paid listings, creating a difficult decision for online retailers and product search companies when considering whether to support paid search listings.
Ranking Versus Categorization: The Effects of Sorting the Results for Web Search Engine Multiterm Queries BIBAFull-Text 1434-1438
  David N. Aurelio; Ronald R. Mourant
Many Web search engine users have difficulty writing search queries and finding a useful query result. One element of ineffective Web searches is that many search engine queries are ambiguous or their results do not include the desired information in their first page. The objective of this research was to investigate the effects of sorting the results of multiterm queries. The sorting methods included Categorizing and Ranking. The dependent variables consisted of user performance and preference measures. Statistical analyses revealed that when the correct result was found on page 1 of the results, the Ranking sorting method was associated with faster trial times, fewer false alarms, higher trial ratings, and the preferred sorting method. However, when the correct result was found on subsequent pages, the Category sorting method was associated with better performance and increased preference.
A Comparison of Subject-Based Classification Strategies for Enhanced Usability BIBAFull-Text 1439-1443
  Vicki Ahlstrom
Collections of documents, such as technical notes, are often classified on websites using a set of keywords that describe general subject areas. These keywords are used as a set of links to help the user navigate to the information he or she is seeking. This subject-based classification is intended to help users find information. A poorly designed subject-based index can make it difficult or impossible for users to find the information they need, however, creating an effective subject-based index is not easy. There are many different classification strategies that can be used. Each of these strategies can result in a different set of key words/key phrases. Some of these strategies may result in an index that is more usable than others. This paper addresses the problem of how to create a subject index that facilitates usability. Several strategies are compared against user search data. The five strategies resulted in differences in search success rate and efficiency.
Culture and Cognition: Implications for Cognitive Design of Learning Resources BIBAFull-Text 1444-1448
  Chang S. Nam; Hyung N. Kim; Tonya L. Smith-Jackson; Wayne A. Scales
The rapid growth of computer-based learning applications has generated the need for the consideration of learning styles of culturally diverse students. However, few attempts have been made to empirically study the influence of learner's cultural backgrounds on computer-based learning. Many studies have shown that mismatches between students' cultural learning preferences and pedagogy may negatively affect their academic performance and attitudes toward learning. The primary purpose of the study was to evaluate a Web-based tutorial for global positioning systems (GPS) designed by employing culture-centered interface design guidelines that would be compatible with cultural learning preferences of two ethnic groups -- African- and European-Americans. Results of the study showed that AA students preferred a Web-based tutorial designed with interface design guidelines that were compatible with their cultural learning preferences. There are several implications for culture-centered cognitive design of learning resource.


The Design and Presentation Order of Web Page Buttons BIBAFull-Text 1449-1453
  Aaron W. Bangor; James T. Miller
As part of a guidelines standardization effort, a company wanted to know what customers think a "good" button looks like for web sites. A study was conducted with 63 participants that had them rank-order four existing button designs and then asked follow-up questions about their preference for several button characteristics. Results show that participants preferred bold text for labels, dark characters on a lighter background, rounded corners, and the button and page background colors to be different. One of the four designs was preferred over the other three, even though it embodied only three of the four preferred characteristics. The horizontal ordering of button pairs was also investigated. Participants preferred Save to the left of Cancel and Next to the right of Back, but did not indicate a preference for Continue with respect to Cancel. Possible reasons for these findings and future research topics are discussed.
Effect of Scroll Bar and Navigation Menu Co-Location on Web Performance BIBAFull-Text 1454-1458
  Heather Devine; Anthony D. Andre
This study explored the effect of scroll bar and navigation menu co-location on web performance. Participants interacted with fictitious web sites that co-located the menu and scroll bar, or placed them opposite one another. We did not find support for the hypothesis that menu and scroll bar co-location would result in improved menu navigation performance. However, participants indicated a preference for co-location and found it easier and faster to use than non-co-location. The results show a strong advantage for the conventional right-side placement of the scroll bar and a potential benefit for the unconventional right-side placement of the menu.
Using Eye Tracking to Evaluate Alternative Search Results Interfaces BIBAFull-Text 1459-1463
  Rachana S. Rele; Andrew T. Duchowski
Surveys have shown that 75% of users get frustrated with search engines and only 21% find relevant information. Inability to find relevant results can be partially attributed to cluttered results pages and failure in constructing Boolean queries. This research used sixteen subjects to evaluate two types of search results interfaces using four tasks while measuring performance and studying their ocular behavior using a Tobii 1750 eye-tracker. The two interfaces used were list interface, commonly seen on many search engines and a tabular interface presenting information in discrete categories or elements of the result's abstract. Quantitative comparisons of two interfaces are made on performance metrics such as time and errors, process metrics such as fixation durations, number of fixations, and eye movement transitions from one element or category of the abstract. Subjective data was collected through post-task and post-test questionnaires. The results did not show any significant difference in performance between the two interfaces, however, eye movements analysis provide some insights into importance of search result's abstract elements such as title, summary, and URL of the interface while searching.

MACROERGONOMICS: Macroergonomics in Health Care

Patient Safety Climate (Psc) in Outpatient Surgery Centers Part Two BIBAFull-Text 1464-1468
  Carla J. Alvarado; Pascale Carayon; Ann Schoofs Hundt
We report results of safety climate questions from health care professionals involved in the "Systems Engineering Intervention in Outpatient Surgery -- a Collaborative Community Perspective" study undertaken at the University of Wisconsin-Madison. Surveys were conducted in five outpatient surgery centers pre- and post-intervention. The objectives of this study were to examine patient safety climate across various outpatient surgery centers pre- and post-specific patient safety interventions and to examine the relationship between patient safety climate and job categories, individual outpatient centers and the respondents' Quality of Working Life (QWL). Our results indicate that four patient safety climate scales can be created from the pre- and post-intervention 12-item questionnaire: (1) Top management commitment to patient safety, (2) General patent safety climate, (3) Employee commitment to patient safety and (4) Patient safety change. In one of the survey centers, patient safety climate became more negative over time.
Patient Care Process and Information Flow in Outpatient Surgery BIBAFull-Text 1469-1473
  Kara Schultz; Pascale Carayon; Ann Schoofs Hundt; Scott R. Springman
Patient care transitions have been shown to be critical points at which failure as well as recovery from potential failure may occur. The purpose of this research is to identify transitions in patient care and the flow of information for different steps of the outpatient surgery preoperative care process and, in turn, identify breakdowns in the process of the information flow and their consequences. A study of one hospital's preoperative process in outpatient surgery was conducted. The design of this study involved four data collection methods to gather data on preoperative work processes: employee shadowing, patient shadowing, clinic observation, and dictated feedback from midlevel providers. Various facilitators and obstacles of information flow were found to be present in the preoperative care process that affected the flow of patient information and resulted in negative consequences for healthcare providers and patients.
Handbooks or Mentors The Role of a Resident Physician Manual in Resident Education BIBAFull-Text 1474-1477
  Danny Ho; Yan Xiao; F. Jacob Seagull; Amy Sisley; Richard Dutton; Colin F. Mackenzie
Teaching hospitals with rotating residents face the challenge of training and orienting new personnel. We studied a pocket-sized resident manual used for meeting these challenges in a leading trauma center. This study examines motivations and barriers associated with adopting the resident manual through structured survey and semi-formal interview. Multiple factors shaped the use and effectiveness of the manual, including learning style, organizational culture, and specific usability issues. Findings suggest that organizational culture was the primary determinant of how the resident manual was used, as residents strongly favor attending physicians, fellows, and other residents as their first source of knowledge. Meanwhile, the small form factor of the resident manual afforded optimal accessibility as a quick reference source, but findings suggest enhanced searchability is necessary to realize the manual's full potential. Recommendations for future implementation strategies are made.

MACROERGONOMICS: Participatory Ergonomics and Multicultural Factors in Decision and Computer Work Systems

Initial Development of the Employee Perception of Participatory Ergonomics Questionnaire BIBAFull-Text 1478-1482
  Russell A. Matthews; Jessica A. Gallus
In an organizational context, Participatory ergonomics (PE) programs set out to involve employees in ergonomic design and analysis efforts in order to promote a safer, more user-friendly, and productive workplace. While the purpose of a PE program is to involve employees, currently there is no quantitative method to evaluate the effectiveness of PE programs from the employee's perspective. The current study set out to address this void. Based on a review of the recent published literature, five key constructs were identified as critical evaluative components: Employee Knowledge Base, Employee Involvement, Employee Support, Perceptions of Managerial Support, and Employee Stress due to Ergonomic Changes. With the help of an organizational management-labor committee, a content validity approach was used to generate items. The proposed five-dimension measure was administered to 63 participants working in large manufacturing plant with an established PE program. Initial empirical support for the proposed dimensions was found. Potential uses of the developed measure in a larger context are discussed.
Computer and Information Security Culture: Findings from Two Studies BIBAFull-Text 1483-1487
  Sara Kraemer; Pascale Carayon
This research outlines some dimensions of computer and information security (CIS) culture. Two exploratory studies were conducted to identify the various dimensions of CIS culture. One study included an industry workgroup consisting of six CIS managers and specialists. The second study consisted of individual interviews with eight CIS managers and managers and eight network administrators. The workgroup and CIS managers and network administrators provided a preliminary list of elements in CIS culture dimensions, including: employee participation, training, hiring practices, reward system, management commitment, and communication and feedback.
Going Paperless in Mission Readiness Management: Challenges to Designing a Readiness Management Work Support System BIBAFull-Text 1488-1492
  Kelly Neville; Dawn L. Riddle; Amanda Hafich; H. Barbara Sorensen
This paper describes a recordkeeping and readiness management support system designed to replace and extend a paper-based system used in a large military organization. The focus of the paper is a set of system design challenges that are particularly relevant to the present effort. These challenges involve gaining user acceptance; anticipating changes and variations in work practices; understanding and accommodating macroergonomic factors; and facilitating information access and use.
Multicultural Considerations in Work Processes BIBAFull-Text 1493-1497
  Holly A. H. Handley; Nancy J. Heacox
The Integrative Decision Space (I-DecS), a multi-faceted model with accompanying simulation algorithm, was designed to facilitate modeling and simulation of cultural differences among personnel in a work process. This system, originally developed for military coalitions, has been extended to address issues facing multinational corporations. Factors that influence the decision process of both individual and team decision-makers have been identified. A system architecture was developed that includes component models for work processes, cultural predispositions, organizational climate, personnel experience and training, and the complexity of the specific tasks. The interaction of these models using the integrating algorithm provides a multi-faceted view of a decision process. As multinational corporations address issues of globalization, the I-DecS Analytical System (AnSys) can offer insights to the consequences of multiple cultures interacting in a work process.

MACROERGONOMICS: Trends in Macroergonomics

The State, Trends and Future of Macroergonomics BIBAFull-Text 1498
  Hal W. Hendrick; Pascale Carayon; Michelle Robertson; Brian M. Kleiner
Key developments from ODAM VIII will be used to summarize the state of this important sub-discipline of Human Factors and Ergonomics. This summary will include the methods currently being employed and an impact evaluation. Traditional pitfalls to system design include technology-driven design, a leftover approach to function and task allocation/design and a failure to consider the sociotechnical characteristics of work systems. As a result, many systems have failed and the reputation of ergonomics has suffered. Clearly, as represented around the world, many ergonomists have found success by considering organizational design and management factors in system design and through the emerging science of Macroergonomics, the study of work systems. Macroergonomics focuses on the analysis and design of work systems, which are comprised of two or more persons interacting with some form of (1) hardware and/or software, (2) internal environment, (3) external environment, and (4) an organizational design. Since the environmental factors are perhaps the most important determinants of organizational success, it is useful to understand the application of macroergonomic methods and tools in various environments. We will highlight the need to first understand macroergonomic methods and tools, second to apply these methods and tools within particular work environments and third, to measure and evaluate the effects of human well-being and performance. Based on the results of macroergonomics interventions, the future of macroergonomics will be predicted.


Separate Sides of the Same Coin: Organization Design and (Good) Design of a Decision Support Tool BIBAFull-Text 1499-1503
  Nancy J. Heacox; Holly A. H. Handley
A decision support tool has been designed to allow operations planners to incorporate organizational and cultural factors into the building of effective multinational mission forces. Development of this tool was guided by principles from Human Factors and the Congruence Model of organizations. A user-centered design process was employed. The work process of the target user was analyzed and formed the basis for the steps in the tool's work process. The tool contains several databases that allow a user to build alternate task-staffing configurations associated with a mission plan. The tool simulates the projected performance of these configurations, based on characteristics of tasks, assigned units, and command arrangements. Planners are provided with a macro-level perspective of the mission structure as the operation is staffed; the tool enables them to construct the "best fit" from the operational requirements and the tasking resources at their disposal.
Cooperative Research Incentives: Lessons Learned Using Students as Experimental Subjects BIBAFull-Text 1504-1507
  Charlene A. Yauch; Daniel O. Navaresse
This paper reviews two experiments in which student volunteers were employed for research on cooperative and competitive behaviors. In both experiments the students were given the opportunity to earn incentive pay; the independent variable was the offering of incentives on either a competitive or cooperative basis. The researchers expected the incentives to influence the students' behaviors but found that some behaviors contradicted the expectations, particularly for the cooperative treatments. In both experiments, limited cooperation occurred despite the incentives offered. This paper presents a brief literature review, the experimental methods, incentives used, and instructions given to the subjects. It then reviews the behaviors observed and summarizes lessons learned to assist other researchers that want to minimize problems and increase validity when conducting research experiments where cooperation is expected or encouraged.

PERCEPTION AND PERFORMANCE: Attention/Vigilance/Alarms

Combating Cry Wolf: The Effects of Synthetic Verbal Alarm Urgency on Choice Reaction Performance BIBAFull-Text 1508-1512
  Corey K. Fallon; Ernesto A. Bustamante; James P. Bliss; Brittany L. Anderson
Researchers have shown that increasing the perceived urgency of nonverbal auditory alarms can meliorate alarm response performance degradation due to the cry wolf effect. We conducted two experiments to examine the effects of verbal alarm urgency on the cry wolf effect. Experiment 1 revealed that participants responded significantly less often and correctly rejected more urgent alarms. Experiment 2 revealed that the results in Experiment 1 were contingent on the presence of additional task critical information. Response degradation due to the cry wolf effect was not moderated by alarm urgency in either study. However, the results suggest that performance may still benefit from increased alarm urgency provided additional task critical information is available. These results can be utilized to design verbal alarm systems that evoke more appropriate reactions to false alarms.
A Signal Detection Analysis of the Effects of Workload, Task-Critical and Likelihood Information on Human Alarm Response BIBAFull-Text 1513-1517
  Ernesto A. Bustamante
The purpose of this study was to examine the effects of task-critical and likelihood information on participants' sensitivity and bias to alarm signals under varying levels of workload. Participants performed a complex primary task at the same time they performed a secondary task. Likelihood information was manipulated through the use of either a Binary Alarm System (BAS) or a Likelihood Alarm System (LAS). As expected, task-critical and likelihood information significantly increased participants' sensitivity, and this varied across workload levels. Participants benefited from task-critical information only when they were interacting with the BAS. However, participants benefited from likelihood information regardless of task-critical information, particularly under high-workload conditions. Furthermore, task-critical information increased participants' response bias under low workload, making them less likely to respond to alarm signals. These results demonstrated the superior advantage of an LAS over a traditional BAS and showed support for the use of an LAS as a way to mitigate the cry-wolf effect above and beyond task-critical information.
Concurrent Monitoring for Multiple Critical Signals in a Complex Display: A Vigilance Perspective BIBAFull-Text 1518-1522
  Nathan R. Bailey; Mark W. Scerbo
The present study was designed to examine the monitoring performance of operators in a complex environment requiring concurrent monitoring of multiple displays with different types of critical signals. Participants performed a manual flight task concurrently with three monitoring tasks over three separate 2-hour sessions. The monitoring tasks required operators to detect deviations in the gauge, mode, and digital readout portions of a simulated EICAS display. Results indicated that while performance on the primary flight task degraded within each session, monitoring performance remained constant. Further, intrasession monitoring performance did not degrade across trials. These findings suggest that vigilance performance for complex displays may be influenced by a number of factors including compensatory strategies related to mental effort regulation, the complexity of monitoring task demands, the duration of the monitoring session, and the nature of additional operator responsibilities.
Demand Transitions and Tracking Performance Efficiency: Structural and Strategic Models BIBAFull-Text 1523-1526
  Nathaniel R. Ungar; Gerald Matthews; Joel S. Warm; William N. Dember; John K. Thomas; Victor S. Finomore; Tyler H. Shaw
A compensatory tracking task with hard and easy levels of difficulty was used to test resource depletion and effort regulation models of dual-to-single task transition effects. Both models were supported by the data. Consistent with a resource depletion view, participants who shared the difficult tracking task with a vigilance task during an induction phase, and then performed the tracking task alone during a transition phase, had greater levels of tracking error in both phases than those who were confronted only with the tracking task. By contrast, in accord with expectations derived from the effort regulation view, tracking error on the easy task was smaller during both phases of the study for participants who originally shared tracking with vigilance than for those confronted only with the tracking task. Evidently, task difficulty is a key factor in determining the domains in which these models apply.
How late can you Update Detecting Blur and Transients in Gaze-Contingent Multi-Resolutional Displays BIBAFull-Text 1527-1530
  Lester C. Loschky; George W. McConkie
This study investigated perceptual disruptions in gaze-contingent multi-resolutional displays (GCMRDs) due to delays in updating the image after an eye movement. GCMRDs can be used to save processing resources and transmission bandwidth in many single-user display applications such as virtual reality, simulators, video-telephony, remote piloting, and teleoperation. The current study found that image update delays after an eye movement could be as long as 60 ms without significantly increasing the detectability of image degradation and/or transients due to the update. This is good news for designers of GCMRD applications, since it is ample time to update their displays after an eye movement without disrupting perception.


Steering Errors may Result from Non-Rigid Transparent Optical Flow BIBAFull-Text 1531-1534
  Brian P. Dyre; Roger Lew
Transparent, non-rigid optical flow can result from environmental factors (e.g., wind-blown snow) or technological factors (e.g., superposition of sensor imagery flow on the environmental flow viewed directly through the windscreen) and can produce systematic errors in judgments of the direction of heading and control of yaw. Here, we examined whether these systematic errors generalize to control of heading in a more realistic scenario, driving across a textured ground plane through falling snow. Simulated crosswinds caused the snow to move at varying angles (0-32°) relative to the simulated direction of translation. Participants were instructed to steer such that they maintained a straight path relative to the ground plane. For non-zero angles, a pattern of systematic steering errors was found that was consistent with the pattern of errors previously observed with judgments of heading. These results suggest that motion transparency occurring in more realistic simulations can introduce systematic errors in controlling vehicles.
Visual Displays of Route Properties in Route Guidance Systems: Effects on Driving Performance and Route Selection BIBAFull-Text 1535-1539
  Talia Lavie; Joachim Meyer; Klaus-Josef Bengler; Joseph F. Coughlin
Route guidance systems are predominant examples for in-vehicle telematic systems. The format in which the information is presented in these systems determines the ease of interacting with the system and may influence driving performance. An experiment compared the effects of a table, a separable bar graph and an integrated object display on the time required for route selection, driving performance and subjective evaluations of route guidance information. The integrated display was superior in performance times and participants' preferences and led to the least lane deviations in a driving simulator study. The tabular display led to the most accurate performance. The study provides information on issues related to information display in telematic systems and on the effects the display and system use may have on driving performance. These issues need to be taken into account when designing next generation telematic systems.
An Investigation of the Potential to Influence Braking Behaviour through Manipulation of Optical Looming Cues in a Simulated Driving Task BIBAFull-Text 1540-1544
  Zhonghai Li; Paul Milgram
This paper reports on an investigation of how manipulation of optical looming cues can influence braking behaviour, for automobile driving in a low-fidelity simulator. Twenty participants were instructed to follow a leading vehicle (LV) and appropriately respond to braking events of the LV, which occurred randomly and at different deceleration rates. During some braking events, the size of the LV was manipulated in different ways, without subjects being aware, in a manner concordant with the optical expansion that would have been observed during braking if the LV had been displaced to be closer or further away. Results showed that subjects braked sooner when confronting an expanding LV and later for a contracting LV, relative to a constant-size LV, to an extent corresponding to the magnitude of the manipulation. The experiment supports the theory that drivers use TTC information derived from optic looming to control braking.
Task and Effector Constraints on the Kinematics of Pointing Movements BIBAFull-Text 1545-1548
  Michael Bohan; Daniel McConnell; Shelby Thompson; Alex Chaparro
Recent work has emphasized the distinction between task and effector constraints underlying performance in Fitts' type discrete pointing tasks. We explored the relative contributions of these constraints in a cursor-pointing task by manipulating the control-display scale, thereby dissociating movement scale at the level of the hand from movement scale at the level of the cursor. Using linear regressions to predict movement time, we found that effector constraints best predict the primary transport phase of the movement, bringing the hand near the target. Visual task constraints underlie the secondary target acquisition phase of the movement. We present a reformulation of Fitts' (1954) index of difficulty, capturing the relative contributions of effector and visual task constraints.
Attention Performance After Exposure to Combined Noise and Whole-Body Vibration BIBAFull-Text 1549-1553
  Jessica Ljungberg; Gregory Neely
An experimental study with 24 male subjects between 21 and 30 years (X= 25, SD= 2.4) was conducted. The objective was to investigate post-exposure effects in attention performance after exposure to noise, a whole-body vibration, both factors combined and a control condition. Another aim was to explore if participants would have more degraded performance after exposure to the combined condition compared to just one single stimuli. Both the noise (78 dB(A)) and vibration stimuli (1.1 m/s2 r.m.s) was similar to those that are typically for a forest machine. Results showed no combined effects but an after-effect was detected generated by the vibration exposure. The participants had performed significantly poorer in the attention task after exposure to vibration exposure compared to no exposure at all. While not reaching a statistically significant level, even the performance in the other experimental conditions was poorer than in the control condition.

PERCEPTION AND PERFORMANCE: Overarching Principles of Display Design

Overarching Principles of Display Design BIBAFull-Text 1554-1555
  Harvey S. Smallman
As an applied scientific discipline studying the interface between people and technology, Human Factors and Ergonomics (HF/E) has a variety of goals. One primary goal is to codify its science into a set of predictive principles and guidelines for the design of technology. This is important for several reasons. First is to provide practical, useful guidance to technology developers and designers to maximize the chances that their artifacts will be accepted, liked and perform well. The second reason is the general intellectual motivation of any maturing scientific discipline to operationalize its accumulated knowledge as laws that feed guiding principles for the use of others. Third is that without predictive principles, HF/E runs the risk of becoming -- or at least of being perceived as no more than -- an arbitrary series of applied case studies that do not build one on the next to inform, constrain and improve future designs. This symposium will review the state of display principles and discuss how HF/E can further the codification of its knowledge base so that display design can start to become more science than art.
Choosing the Best from the Good: Display Engineering Principles BIBAFull-Text 1556-1560
  Catherine M. Burns
Most guidance documents on display design either provide a rigid design standard or a list of high level principles. I argue that neither of these approaches is adequate for a complex display design effort. We need instead to develop a category of higher level "display engineering" principles and methods that can consistently drive a professional display designer to best practices in display design. While this concept of display engineering principles still needs development, I will propose two example display engineering practices, graphical object sensitivity analysis and display design with a margin of safety as examples of what could be gained by establishing a systematic display engineering process.
On Redundancy in the Design of Spatial Instruments BIBAFull-Text 1561-1563
  Stephen R. Ellis
Alternative formats for information displays are sometimes identified as being best suited for presentation of particular types of information. This view is assessed in terms of the role of noise and distortion in the presentation of spatial information. It is shown that introduction of redundant elements may compensate for weaknesses in different formats. Consequently, it is argued that the observed differences among formats may in fact arise from specific design decisions relating to the redundancy in the presented information rather than features inherent to the formats themselves.
Naive Realism: Limits of Realism as a Display Principle BIBAFull-Text 1564-1568
  Harvey S. Smallman; Mark St. John
Display designers are often called upon to create visualizations of complex geo-spatial environments for users engaged in tasks such as civil emergency, air traffic, or military operations. What visualization principles exist to guide them? One principle is to strive towards realism, on the belief that realistic depictions result in near effortless comprehension. We think this faith in realism is misplaced and term this misplaced faith Naïve Realism. Naïve Realism appears to stem from the folk belief that scene perception is simple, accurate, and rich, when, in fact, perception is remarkably complex, error-prone, and sparse. It results in the development of realistic displays that give users flawed, imprecise representations. Therefore, Naïve Realism offers a new account of why users sometimes prefer displays that subsequently under-perform. We review the evidence for Naïve Realism, its origins, why it persists, and conclude with a discussion of how good design can counteract it.
Allocating Bits to Displays for Dynamic Control: When More is More and When More is Less BIBAFull-Text 1569-1572
  Thomas B. Sheridan
This symposium provides the opportunity to address not only the stated topic of "naïve realism" but also to discuss some surrounding issues about display design. My paper reviews four relationships between information variables as related to design of displays for dynamic control tasks. It raises questions about what we need to know but don't. All four are themes that have been visited before in different display applications and contexts, but deserve to be quantified and interrelated. They are: (1) the "amount" of information presented in a display; (2) the simultaneous presentation of both past and predicted future information along with present state; (3) the abstraction versus realism tradeoff (naïve realism?); and (4) the issue of whether "immersion" in a virtual reality improves performance. I certainly make no claim of ability to tie them into a unified formal comprehensive structure at this time, but I think considering them in juxtaposition can be suggestive of proper allocation when best performance is the main goal.


Viewpoint Tethering in Complex Terrain Navigation and Awareness BIBAFull-Text 1573-1577
  Matthew Lamb; J. G. Hollands
Twelve participants navigated a simulated vehicle across complex virtual terrain using five different display viewpoints: egocentric, dynamic tether, rigid tether, three-dimensional (3D) exocentric, and two-dimensional (2D) exocentric. While navigating, participants had to avoid being seen by simulated enemy units. After the navigation task, participants' spatial awareness was assessed using a recognition task. The egocentric display was more effective than exocentric displays (2D or 3D) for navigation, and the exocentric displays were more effective than egocentric for time seen during navigation and the recognition task. The tethered displays generally produced intermediate results, but minimized the time during which the participant's avatar was visible to enemy positions. In summary, it would appear that the tether facilitated spatial awareness involving knowledge of locations of interest with respect to one's own position while navigating.
Evaluation of a Collaborative Movement Task in a Distributed Three-Dimensional Virtual Environment BIBAFull-Text 1578-1582
  Julio C. Mateo; Joseph T. Manning; Jeffrey L. Cowgill; Thomas J. Moore; Robert H. Gilkey
A task designed to estimate the impact of communication channel performance on individual and collaborative human performance in distributed, shared, virtual environments was evaluated. The 'Fitts-like' task required participants to press buttons as fast as they could in a three-dimensional virtual workspace. In addition, in the collaborative task the 2 participants were required to press the buttons simultaneously. The size of the buttons, the distance between buttons, and the delay between movement and visual feedback were manipulated. The results were well described by Fitts' law. Movement Time increased with increases in Index of Difficulty and delay. The Index of Performance decreased with delay and was lower in the collaborative task. Overall, orderly changes in performance were observed with manipulation of task parameters, suggesting that future studies to examine more complicated manipulations of network performance and multisensory displays are appropriate.
Displaying Depth in Computer Systems: Lessons from Two-Dimensional Works of Art BIBAFull-Text 1583-1587
  Skye Lee Pazuchanics; Douglas J. Gillan
Virtual depth displays depend on static, monocular cues. Models of integrating monocular cues may be continuous (additive) or discontinuous. Previous research using simple displays and a small number of cues supported continuous cue integration. The present research is designed to expand the understanding of how the visual system integrates information from multiple pictorial cues by investigating combinations of one to ten pictorial cues in visually-rich, two-dimensional displays (paintings and photographs). Participants estimated depth in target paintings and photographs relative to a standard two dimensional display. Certain results suggest that the visual system integrates cues in a largely additive way, but after a number of cues are present there may be an additional boost in perceived depth resulting in a best-fitting discontinuous model of cue combination. However, this discontinuous effect may be due to design decisions made by the painters rather than exclusively to the perceptual processes of the viewers. Analyses of these design decisions provide lessons for the design of two-dimensional displays.
Static Representation of Object Motion BIBAFull-Text 1588-1592
  Douglas J. Gillan; Merrill V. Sapp
Displaying motion information is useful in dynamic tasks, such as tracking or predicting the course of moving objects or systems (e.g., unmanned ground or air vehicles, troops, or weather). Static representations of object motion may be useful when technological limitations prevent use of dynamic displays. The present experiment examined people's interpretations of a variety of static cues to represent object motion. Participants viewed and rated two static types of representation of object motion -- motion lines and arrows. The features of object motion that participants rated were distance traveled, direction, path, speed, and acceleration. The results show that observers reliably interpret certain static cues to represent features of object motion, especially distance, direction, path and speed; the cues examined were not interpreted as representing acceleration. The results are interpreted as guidelines for design of displays that include object motion information.
Common Region and Spatial Performance using Map-Like Displays BIBAFull-Text 1593-1597
  Karel Hurts
Three techniques of perceptual grouping were compared in terms of their effect on people's ability to read maps that always remained visible. The techniques differ in the way they create clusters of objects on map-like displays: by using boundary lines to form adjacent "countries" (Common Region), by coloring "city" symbols that belong to the same, contiguous, country in a unique way (Adjacent Color), or by using color to create spatially non-contiguous, overlapping, clusters (Color Only). Subjects were asked to compare the horizontal orientations of two cities at a time, and, in another task, to compare two distances corresponding to three map cities. Results show that orientation statements were verified faster for same-cluster cities than for different-cluster cities, but only in the Common Region condition. Neither distance estimations nor orientation judgments were distorted by any grouping technique, as indicated by an effect on judgment accuracy. The implications of these results for our understanding of map reading ability in relation to techniques for perceptual grouping are discussed.

PERCEPTION AND PERFORMANCE: Audio Displays & Sonification

Conceptual Versus Perceptual Training for Auditory Graphs BIBAFull-Text 1598-1601
  Bruce N. Walker; Michael A. Nees
A study examined different types of brief training for performance of a point estimation task with a sonified graph of quantitative data. For a given trial, participants estimated the price of a stock at a randomly selected hour of a 10-hour trading day as displayed by an auditory graph of the stock price. Sixty Georgia Tech undergraduate students completed a pre-test, an experimental training session, and a post-test for the point estimation task. In an extension of Smith and Walker (in press), a highly conceptual, task analysis-derived method of training was examined along with training paradigms that used either practice alone, prompting of correct responses, or feedback for correct answers during the training session. A control group completed a filler task during training. Results indicated that practice with feedback during training produced better post-test scores than the control condition.
Spatial Audio as a Navigation Aid and Attitude Indicator BIBAFull-Text 1602-1606
  Brian D. Simpson; Douglas S. Brungart; Ronald C. Dallman; Jacque Joffrion; Michael D. Presnar; Robert H. Gilkey
Most current display systems in general aviation (GA) environments employ, at best, relatively simple audio displays that do not fully exploit a pilot's auditory processing capabilities. Spatial audio displays, however, take advantage of the spatial processing capabilities of the auditory system and have the ability to provide, in an intuitive manner, comprehensive information about the status of an aircraft to the pilot. This paper describes a study conducted in order to assess the utility of spatial audio as (1) a navigation aid, and (2) an attitude indicator in an actual flight environment. Performance was measured in tasks requiring pilots to fly in the direction of a spatial audio "navigation beacon" and use an auditory artificial horizon display to detect changes in attitude and maintain straight and level flight when no visual cues were available. The results indicate that spatial audio displays can effectively be used by pilots for both navigation and attitude monitoring, and thus may be a valuable tool in supporting pilot situation awareness and improving overall safety in GA environments.
Development and Evaluation of a System for Wearable Audio Navigation BIBAFull-Text 1607-1609
  Bruce N. Walker; Jeffrey Lindsay
If it is not possible to use vision when navigating through one's surroundings, moving safely and effectively becomes much harder. In such cases, non-speech audio cues can serve as navigation beacons, as well as denote features in the environment relevant to the user. This paper outlines and summarizes the development and evaluation of a System for Wearable Audio Navigation (SWAN), including an overview of completed, ongoing, and future research relating to the sounds used, the human-system interaction, output hardware, divided attention, and task effects.
Optimizing Alarm Location and Effects of Hearing Protection for Machining Industries BIBAFull-Text 1610-1614
  Jun-Seok Lee; Dongjoon Kong
Emergency alarm systems are extremely important in our daily life since these can provide adequate and timely warning to people in event of threatened disaster. These systems cause a traumatic hearing loss due to their extremely high sound level. Hearing protection devices are the most popular and convenient solution for avoiding a traumatic hearing loss. However, the study of alarm location problems with hearing protection has not been much paid attention. The purposes of this study were; (1) to determine the number of alarm devices, their optimum locations and minimum sound power levels and; (2) to find the effectiveness of hearing protection devices. The selected working environment was a machining facility that usually generates extremely high noise level. An analytical model was provided and the effects of hearing protection devices were discussed with two examples. The results showed that hearing protection was highly required at or above 85dBA noisy environment.
Evaluation of Bone-Conduction Headsets for use in Multitalker Communication Environments BIBAFull-Text 1615-1619
  Bruce N. Walker; Raymond M. Stanley; Nandini Iyer; Brian D. Simpson; Douglas S. Brungart
Standard audio headphones are useful in many applications, but they cover the ears of the listener and thus may impair the perception of ambient sounds. Bone-conduction headphones offer a possible alternative, but traditionally their use has been limited to monaural applications due to the high propagation speed of sound in the human skull. Here we show that stereo bone-conduction headsets can be used to provide a limited amount of interaural isolation in a dichotic speech perception task. The results suggest that reliable spatial separation is possible with bone-conduction headsets, but that they probably cannot be used to lateralize signals to extreme left or right apparent locations.

PERCEPTION AND PERFORMANCE: Issues in Object Identification and Motion in Complex Displays

Metacognitive Judgments in a Simulated Luggage Screening Task BIBAFull-Text 1620-1624
  Jason S. McCarley; Jessica Gosney
A pair of experiments examined the accuracy and potential role of predictive metacognitive judgments in a simulated baggage screening task. Procedure was modeled after the ease-of-learning task (Underwood, 1966). Subjects searched for knives hidden in x-ray images of passenger bags. Before performing the search task, subjects viewed each stimulus without the embedded target and rated the likelihood of finding the target if it was hidden in that image. Experiment 1 used a 2IFC search task. Experiment 2 used a speeded yes-no search procedure. Results suggest that predictive metacognitive judgments are only modestly accurate, but that the information on which such judgments are based is nonetheless used to regulate search behavior.
The Role of Motion in Object Recognition BIBAFull-Text 1625-1629
  Charles L. Harrison; Douglas J. Gillan
Do motion cues influence object recognition when contour information is available? Three experiments examined four motion conditions for a variety of objects (no motion, random motion, atypical motion, and typical motion) when contour information was also available. A typical motion pattern was one that would normally be associated with the moving object, whereas atypical motion involved a regular motion pattern that was typical for one object in the set of 15 used in the experiments, but wasn't associated with the object in motion. In Experiments 1 and 2, the objects were made difficult to recognize, by eliminating vertices and by using small representations, respectively. In Experiment 3, large, complete contour wire frame pictures were used. In all experiments, recognition speed and accuracy were best for the typical motion condition and second best for the atypical motion. With easily-recognized objects, random motion led to faster recognition than no motion, whereas, with difficult recognition, random motion led to slower response times than no motion. The results are interpreted with a three-process model. Applications to the design of computer icons, signage, and camouflage are discussed.
Magnitude Estimation of Velocity in the X, Y, And Z Axes BIBAFull-Text 1630-1634
  Sommer N. Thompson; Nathan R. Bailey; Mark W. Scerbo
The present study examined the perception of velocity along different axes. Participants viewed the movement of two small circles on a computer display and gave verbal responses for the perceived velocity of one of the circles relative to the other using the psychophysical method of magnitude estimation. Stimuli were presented along the x, y, and z axes. Other variables included direction traveled, time and distance constant, and velocity. Movement in the z axis was represented through angular expansion. As expected, results indicated that velocity judgments increased with increases in stimulus velocity. Perceived velocity was expected to be higher for vertical as compared to horizontal stimuli. The results provided partial support for this hypothesis. Estimates for velocity along the z axis were qualitatively different than for the other two axes. Further, velocity estimates depended upon whether the time or distance was held constant and suggest that the perception of velocity is tied to both spatial and temporal properties of the stimuli.
An Examination of Head-Mounted Displays and Task Complexity in an Airborne Command and Control Simulation Environment BIBAFull-Text 1635-1638
  Scott M. Galster; Robert S. Bolia; Rebecca D. Brown; Alison M. Tollner
Technology-induced increases in information availability have elevated the issue of display cluttering in application domains in which display space is limited. To remediate this problem, evaluations of potential display technologies should be conducted. This paper discusses the examination of head-mounted displays (HMDs) in a simulated airborne command and control environment. Twelve participants engaged in tasks in which they were required to retrieve information from one of several display technologies. This information was available via two HMDs, on paper, and on the primary display. Further, as in previous work, the task complexity was also manipulated. The results indicated that the HMDs tested, in general, did not produce a performance benefit over the other methods of information retrieval. However, the HMDs did not show a decrement in performance as previous studies have shown. Potential uses of HMDs and other display technologies are discussed.
The Opto-Kinetic Cervical Reflex Observed in Pilots Viewing a Synthetic Vision Display and Electronic Attitude Indicator BIBAFull-Text 1639-1643
  John Carl Faust
Prior research indicates that during roll maneuvers in visual meteorological conditions (VMC) pilots exhibit the opto-kinetic cervical reflex (OKCR), an instinctive postural response that humans use to maintain awareness of their spatial orientation. This simulator study was conducted to see if a moving-horizon attitude indicator (AI), electronic attitude indicator (EAI), or Synthetic Vision System (SVS) would elicit the OKCR. The current research found evidence of the OKCR in pilots who viewed both an SVS display and an EAI. Pilots viewing a standard moving-horizon AI produced very little OKCR response.


The Influence of Brightness Highlighting on Eye Movements within a Cockpit Display of Traffic Information BIBAFull-Text 1644-1648
  Min-Ju Liao; Stacy Granada; Walter W. Johnson
Several experiments were conducted to examine the effect of brightness highlighting on search of a target aircraft among distractor aircraft within a cockpit display of traffic information (CDTI). The present experiment partially replicated the design of one of these experiments, adding an examination of eye movements. The display presented homogenous all bright, all dim, or mixed bright and dim aircraft. Within the mixed display, target aircraft were non-predictive and either bright or dim. Results showed that with the mixed display, participants yielded slower detection times, exhibited more eye fixations, and searched with longer paths, compared to the homogenous all bright or dim displays. The duration of the fixation and the speed of eye movements did not show any difference between the homogeneous and mixed displays. The present detection time analysis did not replicate previous experimental results and this is likely due to the fewer trials given in the current experiment. The present results demonstrated how using highlighting to segregate information domains may impose costs on visual search performance in the early stages of a search task.
Compressed File Length Predicts Search Time and Errors on Visual Displays BIBAFull-Text 1649-1652
  D. C. Donderi; Sharon McFaddenx
Search times and errors were recorded for targets (a triangle or trapezoid) in marine radar, chart, and radar-chart overlay bitmap computer displays. Lossless JPEG and ZIP compressed file lengths were obtained for each display. The two types of file length were correlated and they predicted both the maximum time to search each display and the number of errors made per search. Compressed file length is analogous to algorithmic complexity, a theoretical measure of bit string complexity. It predicts both subjective complexity judgments (previous research) and search performance (this study) for a set of static marine electronic displays. The data suggest that compressed file length will predict minimum anticipated performance in a range of applied visual search tasks.
The Effects of Active Head Rotation on the Vestibulo-Ocular Reflex During Visual Pursuit of a Target Displayed on the Integrated Helmet and Display Sight Subsystem BIBAFull-Text 1653-1657
  William R. Bailey
Military helicopter pilots are relying more on night vision devices as the number of night operations continues to increase. However, previous studies have indicated that night vision devices do not provide adequate peripheral orientation and motion cues. This study aimed to develop a new technique for examining sustained reductions in the vestibulo-ocular reflex (VOR) as a means of improving motion discrimination among pilots that use night vision devices. Nine participants performed a series of active head rotation tasks designed to establish a baseline VOR measurement in the control condition, and to suppress the VOR in the experimental condition. The results of the active head rotation tasks revealed that the VOR was not significantly reduced in the experimental condition. Future research will be aimed at altering the task duration and stimuli to determine whether active head rotation is capable of reducing the VOR.
An Eye-Tracking Approach to Inattentional Blindness BIBAFull-Text 1658-1662
  Jennifer M. Pappas; Stephanie R. Fishel; Jason D. Moss; Jacob M. Hicks; Teri D. Leech
Inattentional blindness, the act of failing to notice clearly visible, salient objects in one's environment when engaged in a task, is of great interest due to both its commonality and its overall applications. This study attempted to objectively support previous claims made about the inattentional blindness phenomenon using eye tracking data. It was found that even when a stimulus crossed the fovea, not all individuals saw it. It was also discovered that some participants managed to notice the stimulus without fixating on it, in direct opposition to a hypothesis stating that fixation was required to notice a stimulus.
Body Orientation and the Perception of Spatial Auditory and Tactile Cues BIBAFull-Text 1663-1667
  Peter I. Terrence; J. Christopher Brill; Richard D. Gilson
This study investigated the effects of five body orientations (supine, kneeling, sitting, standing, and prone) on perception of spatial auditory and spatial tactile cues along eight equidistant points (45° separation) of the azimuth, using a within-participant design. Participants (N = 30) used a graphics tablet and stylus to indicate the perceived direction indicated by either vibrotactile stimuli applied to the abdomen, or spatial auditory stimuli presented via headphones. Response time data show responses to spatial tactile cues were significantly faster than spatial auditory cues at each body position and for each point along the azimuth, with no significant effects of body orientation. Absolute angle differences between presented and perceived cues were significantly smaller in the tactile condition for five of the eight stimulus positions, with no significant effects of body orientation. Results are discussed in terms of designing multi-sensory directional cues for reducing visual search space for dismounted soldiers.
Improved Tactical Headset: The Effect of Noise Cancellation on Sound Localization BIBAFull-Text 1668-1672
  Edward W. Klein; Jonathan M. Wertz; Daniel R. Smith
Among other dangers, soldiers in combat often risk hearing damage. A new source of damage is an increase in crew compartment noise resulting from the addition of armored protection to Highly Mobile Multi-Wheeled Vehicles (HMMWVs, commonly known as "Humvee"). To protect soldiers, the US Army may replace the current Interim Headset (IH) with an Improved Tactical Headset (ITH), which uses noise cancellation technology. However, decision makers are concerned that the ITH may affect perception. In the current study, twenty-one soldiers were tested for accuracy of sound localization in an 8 x 2 mixed experimental design (Speaker Location x Headset Type). Results indicate soldiers wearing either headset experienced the front/back confusion typically found in the literature; but soldiers wearing the ITH localized sound more accurately when the sounds originated from their rear and right rear. These findings may support the ITH as the preferred intervention.
Effects of Optical Flow and Discrete Warnings on Deceleration Detection during Car Following BIBAFull-Text 1673-1676
  Patricia R. DeLucia; Anand Tharanathan
Tau specifies time-to-contact between a driver and a lead car, and is potentially useful to prevent rear-end collisions. However, studies suggest that time-to-contact judgments are based on multiple information sources and that effective information varies with distance. We focused on three questions: Does a driver's response to a lead car's deceleration occur when the car's optical size, expansion rate, or tau reaches a "critical" value? Does effective information differ for near and far lead cars? Is a driver's response affected by discrete warnings (brake lights and auditory warnings) that occur independently of optical flow information? Results suggested that responses were not based on a critical value of the optical parameters considered here, and were affected by discrete warnings. Further, effective information varied with the distance and deceleration rate of the lead car. Results were consistent with prior proposals that advanced brake warning systems and collision-avoidance warning systems can reduce the incidence of rear-end collisions. Future studies of this kind will help to improve the design of collision-avoidance systems and to reduce rear-end collisions.
Enhancing Perceived Situation Awareness and Reducing Perceived Workload with a Likelihood Alarm Display BIBAFull-Text 1677-1681
  Corey K. Fallon; Ernesto A. Bustamante; James P. Bliss
The researchers investigated the effects of a likelihood alarm display (LAD) on perceptions of workload and situation awareness (SA) during varying degrees of taskload. Twenty-four psychology students reacted to alarms while performing a complex primary task. The researchers examined participants' performances during four experimental sessions. Two conditions of alarm display (binary and likelihood) and task load (low and high) were manipulated within groups. In addition, alarm display order (binary first or likelihood first) and task load order (low first or high first) were examined between groups. Results showed greater SA and reduced workload when participants used a likelihood alarm display and when they experienced low task load. Significant order effects also occurred. This study demonstrated the positive effects of a likelihood alarm display on perceptions of workload and SA, and suggests that LAD use may reduce workload and enhance SA.

PRODUCT DESIGN: Product Design Aesthetics and Methods

An Ergonomic Computer Keyboard for Conventional, Straight Keyboard Users: Ergonomic Research in Generative Product Design BIBAFull-Text 1682-1685
  Hugh E. McLoone; Melissa Jacobson; Peter Clark; Ryan Opina
Straight, conventional keyboards are still the most popular design among those shipped with new personal computer sales and standalone keyboard retail sales. Many keyboard users are reluctant to switch to a more ergonomic keyboard -- designs that reduce awkward wrist postures. Ergonomic research led to a design of a new keyboard providing more ergonomic benefit to the masses of conventional, straight keyboard users while being equally or even more preferred. The result was a keyboard: Microsoft Comfort Curve Keyboard, designed with a subtle split angle of 12° (instead of 24° of traditional ergonomic keyboards), extending the keys' sizes within this split. The design goals were to reduce ulnar deviation and to maintain approachability and typing performance.
Understanding Customer Needs in Designing Automotive Center Consoles BIBAFull-Text 1686-1690
  Vivek D. Bhise; Rashad Hammoudeh; James Dowd; Marc Hayes
This paper presents results of two studies conducted to determine customer needs in designing future center console designs for automotive products. The first study involved an observational survey of 150 vehicles in three parking lots to determine what items people store in their vehicles and the item locations. The data obtained from the survey provided a list of all the stored items, their distribution and their locations inside the vehicle. Papers, bottles, cups, books, bags and sunglasses were most frequently observed items in the vehicles. The second study was conducted to determine storage preferences of items in the center console. A foam-core center console with velcro surfaces was built inside a minivan. Thirty-six drivers were asked to select items that they would carry most often in their vehicles and place them on the center console surfaces. The resulting layouts of stored items were summarized. The summary data were provided to four teams of industrial design and engineering students to create design concepts for future automotive center consoles.
Underlying Theories of Hedonomics for Affective and Pleasurable Design BIBAFull-Text 1691-1695
  Martin G. Helander; Halimahtun M. Khalid
This paper summarizes underlying theories from psychology that can contribute to the further development of the science of Hedonomics. The methodology in this emerging area is immature. Although we do not know fully understand the mechanics of Hedonomics, we can measure emotions and apply the results in designing artifacts which hopefully will be affective and pleasurable. A model for design of pleasurable artifacts and tasks is presented.
Taxonomy of Discretely Manufactured Products for Making Ergonomic Considerations BIBAFull-Text 1696-1700
  Adaeze Nwaigwe; Bart Nnaji
There are hundreds of thousands of everyday products -- from screws and pens to washing machines. Each of these products has certain ergonomic rules that are necessary for designing them for safety and comfort. To efficiently and concisely capture ergonomic design rules relevant to the great variety of products, this paper applied group technology in categorizing discrete manufactured products for ergonomic design. The method of classification was on the basis of user-actions on such products. Ten classes were determined and corresponding ergonomic rules pertinent to each class were stipulated. The taxonomy showed its robustness by accurately determining ergonomic rules relevant to the design of several products. The potential application of this work is to computer-aided design.

PRODUCT DESIGN: The Role of Hedonomics in the Future of Industry, Service, and Product Design

The Role of Hedonomics in the Future of Industry, Service, and Product Design: Panel Overview BIBAFull-Text 1701-1704
  Tal Oron-Gilad; P. A. Hancock
Hedonomics has been defined as "the branch of science which facilitates the pleasant or enjoyable aspects of human-technology interaction." Hedonomics in general is a fairly new area in research and it is evidently new in ergonomics, human factors, usability and human-computer interaction (HCI). During the last ten years there has been a rapid growth in research about affect and pleasure. Considering the lack of interest from the psychological community during much of the 1900's this comes as a surprise. Affective evaluations provide a new and different perspective in Human Factors Engineering. It is not how to evaluate users -- it is how the user evaluates. The research on hedonic values and seductive interfaces is in fact a welcome contrast to issues of safety and productivity, which have dominated human factors and ergonomics (HF/E). In order for industry to adopt these user-evaluating principles (as opposed to user-evaluation principles) it has to be convinced of their practical effectiveness in the workplace. This panel will focus on this issue and the role of Hedonomics in future work environments and products.

PRODUCT DESIGN: Product Design

Evaluation of a Surgeon-Centered Laparoscopic Tool Design to Conventional Tools BIBAFull-Text 1705-1709
  A. E. Trejo; M.-C Jung; D. Oleynikov; M. S. Hallbeck
Surgeon-centered design principles were employed to design an articulating laparoscopic tool. Evaluation of this tool by 38 expert laparoscopic surgeons demonstrated that they believed the new tool could significantly reduce back, shoulder, arm, wrist and hand pain and stiffness. They preferred the new design to conventional designs for comfort and general impression. The added articulation at the grasper tip was deemed a useful addition by 92%; in addition, 89% of the surgeons would purchase the tool once it was on the market. This study demonstrates that good surgeon-centered design can improve a standard laparoscopic tool. It further demonstrates that given a choice between current tools and ergonomically designed tools, laparoscopic surgeons will select the more comfortable, useful tool.
Determination of Trackball and End Effector Diameters in Laparoscopic Tools BIBAFull-Text 1710-1713
  A. E. Trejo; M.-C. Jung; M. S. Hallbeck
As part of a continuous effort of reaching the optimal use of the intuitool, a study was conducted to identify the optimal diameter combination between the trackball and the end effector ball. The task was to simulate the end effector movement during an operation, using different diameter combinations. Twenty students performed the trackball-controlling tasks to move the end effector from an initial position to designated circular-shaped targets. The trackball diameters were 19 mm and 40 mm, and those of the end effector balls were 3 mm, 5 mm, and 10 mm. There were four targets: right, left, up, and down. Travel time, accuracy, and trail deviation were measured as independent variables. Accuracy was not a significant factor showing that all participants followed instructions to reach each target as accurately as possible. The time to reach the target depended both on target location and trackball to end effector ratio individually and in their interaction. It was quickest to get to the upper target compared to all other locations. Trial deviation depended only on the target position and the target location and ratio interaction. The performance of going in a straight line was best for the left and right directions as opposed to up and down using the trackball.
Evaluating the Accessibility of Laser Printers BIBAFull-Text 1714-1718
  Michael A. Rodriguez; Ron Van Buskirk
The US Rehabilitation Act was amended by Congress in 1998 to require Federal agencies to make their electronic and information technology accessible to people with disabilities. IBM is committed to supporting accessible technology. IBM Printing Systems Division and the IBM Accessibility Center have developed checklists, guidelines and methodologies for evaluating printers with respect to the Section 508 Accessibility Requirements (Section 508 home page). This paper describes the methodology and available tools for evaluating the accessibility of laser printers.
A Human Factors Field Evaluation of a Handheld GPS for Dismounted Soldiers BIBAFull-Text 1719-1723
  Pamela A. Savage-Knepshield; John H. Martin
Land navigation is a vital skill for dismounted Soldiers. Global Positioning System (GPS) technology provides the potential to enhance Soldier survivability by allowing Soldiers to precisely identify their location, track friendly troops, plot and share information about enemies, and exploit terrain characteristics when coupled with a topographical map. To evaluate the effectiveness of an improved handheld military GPS receiver, 16 Soldiers participated in a scenario-based usability study during which performance and preference data were collected. Overall, response to the receiver was favorable. However, the study revealed a Soldier-machine interaction that could result in catastrophic consequences on the battlefield. During a simulated call for fire from air support, 38% (6 out of 16) of the participants failed to identify the intended target's position and instead reported their own. This finding and the user interface interventions implemented to resolve it are discussed within the context of human perception and cognition.
Ergonomics Evaluation of the Use of a Handled Shower-Cleaning Tool BIBAFull-Text 1724-1728
  Ira Janowitz; Gary Urbiel Goldner; Sarah S. Scott
Cleaning a bathroom presents several risk factors for acute and cumulative musculoskeletal injury. This study attempted to determine if using a handled tool while cleaning a typical North American bathtub/shower combination reduces the stress placed on the musculoskeletal system when compared to the use of a spray cleaner and sponge. Nineteen right-handed female subjects cleaned a systematically dirtied shower/bathtub combination using a sponge and a handled tool 21 inches long. The subjects' rated their perceived strain and effort both during and after cleaning. Videotape was obtained simultaneously from three cameras at different locations in the test bathroom and subsequently analyzed for postural data. Subjective responses indicated that subjects felt more comfortable while using the handled tool, and the majority of respondents said they preferred it to a typical sponge and spray cleaner. Postural analysis clearly indicated that the handled tool allowed users to remain in more neutral wrist, shoulder, and trunk postures a greater percentage of the time, and enabled them to remain in less awkward, more stable foot and lower extremity positions. The handled tool significantly reduced the percentage of time that subjects spent cleaning the bathtub, but not the entire shower enclosure.

PRODUCT DESIGN: Design Potpourri

Analysis of Assembly Instructions for Children: The Good, the Bad, and the Ugly BIBAFull-Text 1729-1733
  Cortney V. Martin; L. Smith Smith-Jackson
Building toys and models are vital for learning, yet accompanying assembly instructions are often confusing and difficult to use, especially for children. This exploratory study takes the first step toward developing a taxonomy of design variables and identifying features that may have the largest impact on the usability of pictorial assembly instructions. A secondary data analysis is employed comparing product ratings and reviews from an online retailer to the design factors of the corresponding instruction sets. Not surprisingly, results show a tremendous range of design formats and lack of standardization. However, several factors emerged that were associated more often with the instructions of highly rated products including pictures without text, color illustrations, structural and action diagrams, a higher number of instructions per frame, and one or two frames per page.
Human Factors in Digital Rights Management for Consumer Products BIBAFull-Text 1734-1738
  Marc L. Resnick
Digital Rights Management (DRM) is a means through which copyrights can be protected using technology rather than the legal system. It is controversial because it allows content creators to control the level of access that users have to content they have purchased to a much greater degree than ever before. In additional to preventing illegal piracy, DRM allows content creators to prohibit the "Fair Uses" that the legal system has consistently protected. Human factors practitioners involved in the design of electronic devices that use copyrighted media, including computers, music players, gaming systems, cell phones, digital video recorders, and others, must recognize the effects of DRM on consumer product design. When analyzing user requirements, the interaction between DRM software and user behaviors must be considered. User interfaces should be designed to make the constraints imposed by DRM and the access that is supported easily visible. Including a consideration of DRM and its interactions with interface design will increase the likelihood that consumer electronics are successful.
Lessons Learned from Plant Modernization Programs and their Implications for Reactor Design BIBAFull-Text 1739-1742
  John O'Hara; James Higgins; J. Persensky; Paul Lewis
There is renewed interest in nuclear power in the United States and in constructing new reactors within the next decade. The new reactors likely will be based on advanced digital technology unlike most of the current plants. To better understand the human factors issues associated with these advanced systems, we studied plants that have undergone significant modernization using digital technology. Many of the lessons learned from these plants are also applicable to advanced designs and we are analyzing them with the goal of developing guidance for conducting safety reviews to ensure that both the modernization programs and advanced plant designs realize their potential safety and operational benefits and do not adversely impact human performance and safety. The purpose of this paper is to identify the lessons learned from the modernization programs and their implications for design reviews.
Design of Consumer Product Webpages: Experimental Investigations of Aesthetic and Performance Factors BIBAFull-Text 1743-1746
  Kristi E. Schmidt; Yili Liu
Consumer products are increasingly being purchased online, yet the surge in e-commerce for the sale of retail products was not paired with widespread design savvy or consideration for usability. In this paper, two experimental investigations of aesthetic and performance factors affecting the design of consumer product webpages yield results that designers can use to help create webpages that are useful, usable, and desirable in the competitive e-commerce environment. This research shows how aesthetic and overall preference, ease of use, and interaction speed vary as a function of webpage link color and style, quantity of webpage information, loading speed, and display complexity. Aesthetic preference increases as column width, display complexity, and loading speed increase, and varies with link style. Ease of use and interaction time also vary with link style.
Assessing the Distributed Nature of Home Health Information Management to Inform Human Factors Design BIBAFull-Text 1747-1751
  Teresa Zayas-Caban
In order to gain a deeper and more complete understanding of the job of health information management in the home, case studies of four families were carried out. Examination of household layouts, photographs and health information storage behaviors shows that health information is distributed across the household. This information is distributed across spaces. Storage patterns can be associated with where or when the information is used, frequency and urgency of use, and ownership. Using a human factors approach to understanding storage patterns can be of benefit to consumer health informatics designers in developing unique tools to support distributed home health information use.


Muscular Forces and Joint Angles in Small-Handed Pianists: A Pilot Study on the 78 Size Keyboard Versus the Full Size Keyboard BIBAFull-Text 1752-1756
  B. G. Wristen; A. K. G. Wismer; M.-C. Jung; M. S. Hallbeck
This pilot study examined whether the use of a 7/8 keyboard contributed to the physical ease of small-handed pianists in comparison with the conventional piano keyboard. A secondary research question focused on the transition from one keyboard to the other. For the purposes of this study, we adopted David Steinbuhler's postulated hand span of 8 inches or less as defining a "small-handed" pianist. The goal was to measure muscle loading and hand span during performance of the excerpt. Data collection included each participant being monitored using electromyography via surface electrodes, which were attached to the upper back/shoulder, parts of the hand and arm, and the masseter muscle of the jaw. Subjects were also fitted with electrogoniometers to capture how the span from the first metacarpophalangeal (MCP) joint to the fifth MCP joint moved according to performance demands, as well as recording wrist flexion and extension, radial and ulnar deviation. The findings were that small-handed pianists preferred the smaller keyboard and were able to transition smoothly between it and the conventional keyboard. The maximal angle of hand span while playing a difficult piece averaged about 5° smaller on the radial side and 10° smaller on the ulnar side for the 7/8 keyboard, leading to perceived comfort (ease) and better performance as rated by the subjects.
Consumer Knowledge of Tire Maintenance and Aging Hazard BIBAFull-Text 1757
  Michael J. Kalsher; Michael S. Wogalter; Raymond W. Lim; Kenneth R. Laughery
This research suggests that many consumers in the U.S. do not have the knowledge and skills required to carryout proper maintenance on their vehicles tires -- including knowing when to replace them. Many participants in this study did not know that tires have a limited useful safe lifespan with some participants substantially over-estimating it. Consumers need better and more accessible information about tire safety and maintenance, including explicit warnings about the dangers associated with older tires and date of manufacture or expiration dates. Given the significant risk associated with driving with tires that are past their recommended lifespan (e.g., loss-of-control, collisions, and rollovers), manufacturers should develop more effective ways of getting this important information to consumers.
Evaluating Both Usability and Desirability in the Evaluation of Cell Phones: Towards an Integrated Model BIBAFull-Text 1758-1761
  Laura Moody; Joan Burtner
The goal of human-centered product design is to create products that are useful, usable, and desirable. For many years, human factors has been about research, modeling, and evaluating the functional usefulness and usability of products and systems. In recent years, however, the role of emotion in product design has become a 'hot topic' for human factors professionals, and a variety of methods have been developed for identifying emotional needs and the emotional response people have to products. In this paper, a preliminary study aimed at developing an integrated understanding of the functional and emotional aspects of user experience with cell phones is discussed. A variety of techniques were employed and the combined data analyzed to develop a holistic picture of the user experience. We anticipate that the results of the study will serve as 'proof of concept' for future development work.

SAFETY: Arnold Small Lecture in Safety

The Cognitive Neuroscience of Memory: Relations to Human Factors Research BIBAFull-Text 1762
The cognitive neuroscience approach to memory relies on evidence from cognitive, neuropsychological, and neuro-imaging investigations. Though it has led to much experimental and theoretical progress, there has been little or no attempt to relate cognitive neuroscience evidence to the concerns of human factors researchers. This lecture will attempt to bridge the two fields by focusing on recent cognitive neuroscience analyses of memory errors. I have proposed that memory errors can be divided into seven fundamental categories or "sins": transience, absent-mindedness, blocking, misattribution, suggestibility, bias, and persistence. I will first consider broadly how the seven sins might be related to human factors issues. I will then focus on recent studies that illuminate neural processes pertinent to understanding several of the sins, and consider possible implications of the findings for human factors research.

SAFETY: Safety Potpourri

Effect of Sand on the Slipperiness of Ice BIBAFull-Text 1763-1766
  Daniel Johnson
Ice on walkway surfaces increases the chance that a pedestrian will slip and fall. Sand in the amount of 2.2 lb/100 ft2 (10.8 kg/100 m2) increases slip resistance to about 0.5, the commonly accepted minimum slip resistance for a flat, straight walking surface. Ice covered with a layer of water has about the same level of slip resistance but could be more dangerous since the ice may not be perceived.
Case Study on Evacuation Rates within the World Trade Center Towers on September 11, 2001 BIBAFull-Text 1767-1770
  Jeff D. Colwell; Rajiv K. Mongia; Ali Reza
While movement of people in crowds and fire drills has been studied by numerous investigators, little data exist for real fire evacuations. This is largely due to the difficulty in establishing an accurate position-time history for the evacuees. The evacuation of the World Trade Center North and South Towers on September 11, 2001 was unique in that major, catastrophic events occurred at distinct times during the evacuation. In this paper, 14 evacuation case studies are presented in which the evacuee reported their position at these known points in time to the media. From this position-time history, the descent rate of these evacuees could be determined. These descent rates are not necessarily representative of the evacuation population in general, but they do provide some distinct data points which are of value to the fire protection and building evacuation community in assessing evacuation from high-rise buildings.
Communications in Severe Low-Frequency Noise: An Investigation of Microphone Type and Speech Level on Intelligibility and Attenuation BIBAFull-Text 1771-1775
  Ryan L. Urquhart; John G. Casali
Severe (114 dBA) low-frequency-biased noise, characteristic of military tracked vehicles, was used to examine the speech intelligibility and cognitive effects of at-ear noise reductions provided by contrasting microphone technologies. Using two communications microphones (hereafter, "CommMic1 and CommMic2") intended for U.S. Army tank crew members, participants underwent Modified Rhyme intelligibility tests and Complex Cognitive Assessment Battery (CCAB) tests simultaneously in the noise environment while immersed in loading tasks. Results indicated that CommMic2 reduced the noise level at the ear by about 2 dB more than CommMic1. However, CommMic1 yielded significantly better speech intelligibility at a 96 dB speech level. CCAB performance showed an increasing trend with higher speech levels for both communication microphones, but only significantly so for CommMic1. Speech level and communication microphone type did not have an effect on perceived mental workload.
Cognitive Change in Special Forces Personnel Following Stressful Survival Training BIBAFull-Text 1776-1779
  W. C. Harris; P. A. Hancock; C. A. Morogan
Understanding the deterioration in cognitive functioning produced by stress continues to gain in importance due to the increasing demands imposed by technologically sophisticated systems. Although the general deleterious effects of stress are well established, the relative sensitivity of different cognitive functions to stress and the pattern of cognitive recovery with rest have not been fully distinguished. In this paper, we examined the cognitive performance of Special Forces soldiers immediately prior to and immediately following one week of Survival, Evasion, Resistance and Escape (SERE) School training at Ft. Bragg, NC. Post-stress cognitive performance was characterized by significantly increased response time with minimal change in response accuracy. While response time increased for all tasks, memory appears to be most sensitive to stress. Performance returned to pre-stress levels the next morning following one night of sleep. The tasks affected most in the current study differed from changes which follow primarily upon physical stress, implying that the effects of combined psychological and physical stress on cognitive performance differ substantively from the effects of physical demand alone.
The Effect of Social Proof on Weather-Related Decision Making in Aviation BIBAFull-Text 1780-1784
  Eugenio L. Facci; Meredith A. Bell; Razia Nayeem
This paper examines several accident reports to investigate how a pilot's decision-making is influenced by the decisions made by pilots flying in her/his proximity. Among all the possible theories on influence we frame the problem in terms of Cialdini's (1993) concept of social proof, one that seems particularly appropriate for the analysis of accidents that occurred under deteriorating weather conditions in high-density terminal areas. In the paper we argue that, under those conditions, a very critical moment occurs when pilots should start making no-go or divert decisions after a stream of successful takeoffs and landings has been conducted. Following our examination, we highlight potential streams of research that may yield significant results in this area.

SAFETY: Warnings and Decision Making

Predicted Versus Actual Response to Warning Signs and Labels: Examining the Role of ANSI Z535 Features BIBAFull-Text 1785-1789
  J. Paul Frantz; Stephen L. Young; Timothy P. Rhoades; Elaine C. Wisniewski
This study examined the extent to which predicted responses to ANSI Z535-style warning signs and labels correspond to actual responses. In previous studies, lay people's impressions of the influence of warning attributes have not been found to accurately predict actual responses to warnings or to reflect the effects obtained in behavioral studies for different warning conditions. However, these studies have not specifically focused on the connection between predicted and actual responses to warnings that vary according to conformance with an ANSI standard for product warnings. Four warning scenarios were employed in the present study, with warnings varying according to the extent of ANSI-conformance. Participants consistently and incorrectly predicted that people would be more likely to notice and/or comply with warnings that were more consistent with ANSI as opposed to those warnings that were less-consistent with ANSI. Collectively, people/s perception of differences in response to warnings was not consistent with what has been reported in observational studies.
ANSI Z535 Signal Words and the Ability to Infer Hazard and Consequence Information 1992 Versus 2004 BIBAFull-Text 1790-1794
  J. Paul Frantz; Timothy P. Rhoades; Raina J. Shah; Steven M. Hall; Judith J. Isaacson; Charles G. Burhans
This study examined the influence of signal word on the interpretation of a product safety label in 1992 and 2004. It also examined people's ability to infer consequences from a label that did not explicitly state hazard or consequence information. Participants were shown a label with the signal word DANGER, WARNING, or CAUTION, or with no signal word and asked a series of questions regarding willingness to engage in certain activities with the product, perceived degree of hazard associated with engaging in these activities, perceived degree of hazard associated with not heeding the label, and perceived consequences of not heeding the label. Participants were able to infer the type of hazard and other consequence information that was not explicitly stated. Presence or type of signal word did not influence perceived hazardousness or perceived consequences and with one exception did not influence willingness to engage in certain activities. With one minor exception, there were no differences in responses between 1992 and 2004. In a separate analysis, hazard ratings, overall, were lower for signal words when presented second than when presented first.
A Semantic Relatedness Paradigm for Assessing Comprehension of Warning Symbols BIBAFull-Text 1795-1799
  Mary F. Lesch
In order to avoid critical misunderstandings, comprehension of warning symbols must be assessed prior to use. This study implemented a new method for testing warning symbols -- a semantic relatedness task with paired-response contingent scoring. The participant views the symbol with a label and is asked whether the label conveys the meaning of the symbol. On some trials the label is correct whereas, on others, distractors are presented. A symbol is "understood" only if the respondent accepts the correct answer and rejects all alternatives. 48 participants were tested on twenty-eight warning symbols using a semantic relatedness task and a staged questionnaire (Davies et al., 1998). Three types of knowledge were assessed: 1) the symbol's verbal label, 2) required or prohibited actions, and 3) consequences of failing to comply. There was a strong correspondence in scores across the two methods. It is concluded that the semantic relatedness task is an attractive alternative to open-ended and multiple-choice test methods.
Rider Responsibility and Amusement Ride Accidents: An Observational and Consensus Study of Rider Behaviours BIBAFull-Text 1800-1804
  Kathryn Woodcock; Janet Tsao
"Rider responsibility" regulations will oblige riders to comply with rules and safety features and to abide by the range and limits of their abilities. This study observed rider errors and analysed inspectors' reports of undesirable rider and operator behaviours. In most errors, provisions for error prevention and error capturing were ineffective, although error tolerance prevented most injury. While inspectors used a discourse of violation to describe undesirable behaviour, the observed errors were goal oriented and made sense in the rider's task or possible mental model. "Rider responsibility" obligations may not eliminate the contextual aspects of the errors resulting in deviation from the existing safety rules.
A Preliminary Investigation of Costs and Benefits in Dietary Decisions BIBAFull-Text 1805-1809
  Danielle Paige Smith
This paper describes an exploratory study that examined the perceived costs and benefits and general attitudes toward dietary supplements and seeking a doctor's dietary advice. Thirty-five undergraduates completed a survey packet that used various methods to assessed attitudes toward dieting and obesity (i.e. Likert scales, cost-benefit generation, scenario-based decision tasks). Results generally replicate past work, in that participants were unsure about the safety and regulation of dietary supplements, and although physician's advice is important, they were unlikely to seek their doctor's advice prior to beginning to try and lose weight. Further, responses indicated a perception of few risks associated with seeking physician's advice; however, these appear to be weighted heavily when deciding on a dietary method based on the scenario decision-making task. The implications of these results on planned future research are discussed.

SAFETY: Posters

Postural Stability of Commercial Truck Drivers: Impact of Extended Durations of Whole-Body Vibration BIBAFull-Text 1810-1814
  Shaman Ahuja; Jerry Davis; Lloyd R. Wade
Falls from non-moving vehicles constitute a significant portion of fall related fatal occupational injuries, with a yearly average of 48.7 fatal falls, from 1992 to 2002. Whole-body vibration (WBV) has been thought to be a contributing factor to loss of balance, more specifically, falls while descending from a vehicle. The current research employed a "real-time" actual trucking environment, rather than vibration platforms in laboratories, as is typically the case. Nine (9) full-time, long haul truck drivers' drove over 3000 miles in total, while participating in this study. The protocol required postural stability testing prior to, and immediately following, each of three driving sessions of 2.5 hours during a single shift. Results indicate significant changes in postural stability as a result of exposure to extended durations of WBV. The results also showed an increase of sway (cm) at each of the post-test measures compared to the pre-test, and an overall increase over the 8.5 hour shift, suggesting a time dependent increase over the course of the driving shift.
Human Reliability Analysis in the U.S. Nuclear Power Industry: A Comparison of Atomistic and Holistic Methods BIBAFull-Text 1815-1819
  Ronald L. Boring; David I. Gertman; Jeffrey C. Joe; Julie L. Marble
A variety of methods have been developed to generate human error probabilities for use in the US nuclear power industry. When actual operations data are not available, it is necessary for an analyst to estimate these probabilities. Most approaches, including THERP, ASEP, SLIM-MAUD, and SPAR-H, feature an atomistic approach to characterizing and estimating error. The atomistic approach is based on the notion that events and their causes can be decomposed and individually quantified. In contrast, in the holistic approach, such as found in ATHEANA, the analysis centers on the entire event, which is typically quantified as an indivisible whole. The distinction between atomistic and holistic approaches is important in understanding the nature of human reliability analysis quantification and the utility and shortcomings associated with each approach.

STUDENT FORUM: Training and Cognitive Engineering

Eliciting user Analogies to Improve Documentation BIBAFull-Text 1821-1825
  Lisa J. Elliott; Peter W. Foltz
An invisible language barrier exists between users and creators of technology. This mental model disparity has been described as the "gulf of evaluation and the gulf of execution" (Norman, 1988). Typically, when such common ground is lacking, analogies are used. However, it is unclear whether professional writers and system designers have the naïve knowledge necessary to create analogies that users find helpful. Some researchers claim that through discovery learning, users are able to create analogies (Shrager and Klahr, 1985). It is hypothesized that these analogies offer clues to appropriate mental models and to indicate skills needed to aid other new users. Furthermore, analogies elicited from novice users, should produce successful analogies for other users. In the present study, participants receiving analogies created by other users reported an increased level of confidence and more accurate expectations of the results of their actions with a single exposure to the system. This study found the discovery learning method elicited analogies which users found benefit from by reporting an increase of confidence, increase of motivation and increased accuracy in their expectations as the result of their actions thereby narrowing the "gulf of evaluation and the gulf of execution" (Norman, 1988).
Mind as Magnitude: Reconsidering Information Processing in Cognitive Engineering BIBAFull-Text 1826-1830
  Ronald L. Boring; Robert L. West
The purpose of this paper is twofold: (i) to explore how the predominant information processing paradigm has shaped cognitive engineering; (ii) to propose an alternative framework for cognitive engineering, in which magnitude takes equal importance to information categorization. This reconceptualization of cognitive engineering opens up new topics for human factors research as well as new approaches to human factors measurement. It is intended that this paper will highlight a fruitful path for reconsidering information processing in cognitive engineering.
The Effect of Contradictory Information on Recently Acquired Knowledge BIBAFull-Text 1831-1835
  Anne E. Adams; C. Travis Bowles; Ki C. Choi; Wendy A. Rogers; Arthur D. Fisk
When individuals encounter information contradicting their beliefs, they may briefly retain the contradiction, but are likely to revert to their original beliefs over time. Past research has focused on the effects of prior knowledge and consistency of information when prior knowledge was well-established. This study investigated the effects of prior knowledge and information consistency for recently acquired knowledge. By learning whether the same reverting effect holds for recently acquired information, interventions can be sought to enhance recall of important information. Participants in this study were given two information packages about a fictional animal and their recall on various facts tested. Although a large proportion of participants recalled the updated information, overall recall of contradicted information after two weeks was reduced compared to when information was consistent. Recall of the original information was shown to resurface.
The Effect of within Stimulus Presentation in Implicit Sequence Learning BIBAFull-Text 1836-1840
  Timothy A. Nichols; Arthur D. Fisk; Wendy A. Rogers
The tacit and incidental acquisition of sequential information can occur in tasks from air-traffic control to crossing the streets in a crowded metropolis. The present study investigated how implicit sequence learning occurs when attention is divided amongst tasks. Our conceptualization of implicit sequence learning is that dual task interference arises from multiple control processes in the secondary task. This fits with findings that implicit learning remains intact when a within stimulus dual task is employed, where the stimulus for both tasks is incorporated within a single stimulus. However, a direct comparison with the standard dual task condition has not been presented. This comparison revealed another possible explanation for dual task interference in implicit sequence learning, that longer inter-trial intervals, a function of the within stimulus methodology, result in better performance and implicit learning. The data suggest that implicit learning and overall performance in a task that contains an incidental, consistent structure is optimized when stimuli are contained within a single stimulus.
The Influence of Web-Writing Styles on Readers' Mental Text Representation BIBAFull-Text 1841-1845
  Tuan Q. Tran; Peter D. Elgin; Keith S. Jones; Kimberly R. Raddatz; Elizabeth T. Cady
The increasingly popular avenue of web-based distance education places high demand on distance educators to format web pages that facilitate learning. Guidelines regarding appropriate writing styles for web-based distance education, however, do not currently exist. The purpose of this study is to investigate the effects of four different writing styles on the reader's mental representation of web text. Participants will study hypertext written in one of four web-writing styles (e.g., concise, scannable, objective, and combined) and then be given a cued association task intended to measure participants' mental representations of the studied information. It is hypothesized that the scannable and combined styles will bias readers to scan rather than elaborately read which may result in less dense mental representations relative to the objective and concise writing styles. Further, the use of more descriptors in the objective writing style will lead to better integration of ideas and more dense mental representations than the concise writing style.

STUDENT FORUM: Achieving Success in the Hf/E Field: Expert Advice on How to Become a Future Expert!

Achieving Success in the HfE Field: Expert Advice on How to Become a Future Expert BIBAFull-Text 1846-1850
  Janet I. Creaser; Arnold M. Lund; Jeff English; Ronald G. Shapiro; Anthony D. Andre
Welcome to the 12th Annual Human Factors and Ergonomics Career Panel. This year, the panel will impart wisdom on achieving expertise in the HF/E field. First, Jeff English defines for us what it means to be an expert and the steps to take on the journey to expertise. Arnold Lund describes the ingredients individuals possess that help them on their way to expertise and success. Ronald Shapiro will help you conduct a reality check of how you personally define success and set goals to achieve that success. Anthony Andre provides tips for new graduates on getting a job in a market that is increasingly emphasizing experience. Finally, Janet Creaser has a few words about some of the advice she has put into practice in the past two years.

STUDENT FORUM: Human-Computer Interaction

The Effect of Perceived Consequence on Automation Reliance in a Human-Automation Collaborative System BIBAFull-Text 1851-1855
  Neta Ezer; Arthur D. Fisk; Wendy A. Rogers
As automated systems are entering new environments, some of which involve high-risk decision making, it is critical that we understand in what situations people will or will not rely on the recommendations of automated decision aids. It is theorized that in deciding whether to trust automation people consider perceived consequence, weighing the cost associated with inappropriate action or inaction and the psychological cost associated with verifying the aid. This study will address the effect that perceived consequence has on attitudes and behavior toward decision aids by exposing participants to different levels of consequence, manipulated by the cost associated with making a mistake and the cost needed to verify the aid. It is expected that as the cost of making a mistake increases and the cost of verifying the automation decreases, trust and reliance in a decision aid will decrease.
Privacy Perceptions of an Aware Home with Visual Sensing Devices BIBAFull-Text 1856-1858
  Kelly E. Caine; Wendy A. Rogers; Arthur D. Fisk
Homes that can collaborate with their residents rather than simply provide shelter are becoming a reality. These homes such as Georgia Tech's "Aware Home" can potentially provide support to residents. Older adults in particular may benefit from the supports provided by these Aware Homes if they utilize the technologies they offer. The purpose of this study is to explore the privacy concerns that older adults may have about a home equipped with a visual sensing device. Using a structured interview approach we propose to investigate how variables such as the type of images the home captures and the physical and mental health of the residents of the home may affect privacy concerns. Findings from scenario-based structured interviews will be used to better understand the characteristics of these variables and how they relate to privacy concerns about visual sensing devices. Such data are critical for a model of home-based privacy concerns, for better design of home based visual sensing systems, and for providing information about sensing systems so that individuals may make informed choices concerning what devices to have in their homes.
Automation in the Home: The Development of an Appropriate System Representation and Its Effects on Reliance BIBAFull-Text 1859-1862
  Julian Sanchez; Gina Calcaterra; Quan Q. Tran
To achieve an appropriate level of reliance on an automated system, the operator must have an accurate system representation such that he/she is aware of the capabilities and limitations of the system. The appropriate use of an automated system can lead to optimal performance by the human-machine dyad. This study investigates the relationship between an accurate system representation and behaviors associated with human-automation interaction (e.g., reliance). Furthermore, age-related effects are also included in the investigation. A cooking memory aid (Cook/s Collage) is used as an automated aid that keeps track of the ingredients used in a specific recipe. Participants are asked to interact with the automated device for 5 sessions (each on different days). Tasks are structured to simulate those in a real kitchen. Preliminary results suggest that there is a different pattern of interaction with the aid as a function of age. Older adults tend to rely on the aid for real-time feedback while younger adults use the aid as a verification tool that they have executed the recipe as desired.
Exploring the Role of Shared Mental Models for Implicit Coordination in Teams BIBAFull-Text 1863-1867
  Raegan M. Hoeft; Florian Jentsch; Kimberly Smith-Jentsch; Clint Bowers
Previous research has suggested that when high-performing teams are experiencing increased workload, they will adaptively shift from explicit to more implicit forms of coordination. This is thought to occur because the team members have shared mental models (SMMs) which allow them to anticipate one another's needs. However, it is currently not known how SMMs are related to implicit coordination. Much of the research on SMMs had focused on the actual level of sharedness and, to some degree, on the accuracy of each team member's model. However, to our knowledge, none has investigated the relationship between SMMs and implicit coordination. Furthermore, one line of research that has received very little attention is the notion of perceptions of sharedness. Must team members have an accurate perception of how well they share mental models in order to exploit them via implicit coordination?The purpose of this paper is to explore these fundamental questions that drive the process of implicit coordination.

STUDENT FORUM: Virtual Environments

Gender Differences in Navigation and Wayfinding Using Mobile Augmented Reality BIBAFull-Text 1868-1872
  Ali M. Ahmad; Brian F. Goldiez; P. A. Hancock
Augmented Reality (AR) technology is sufficiently mature, where it is possible to evaluate improvement in human performance. A critical aspect of human performance is individual differences in AR. In the present study, the effect of gender on human performance in a "search and rescue" navigation task is assessed. Six conditions were investigated in the study: Two control conditions (paper map or compass prior to entering the maze), and four experimental conditions (combinations of egocentric and exocentric maps, and a continuously-on or on-demand map display). 120 subjects equally divided between males and females were tested. Pre and post test questionnaires were administered. Guilford-Zimmerman (G-Z) scores indicate that males perform better than females in spatial visualization and orientation tasks. The time for maze traversal for females exceeded that of males by 127 seconds on average for the no map condition. Also, males had better performance in covering the maze.
Spatial Orientation with a Prominent Hallway Landmark BIBAFull-Text 1873-1877
  Lisa J. Douglas; Herbert A. Colle
The design of 3-D perspective interfaces can be facilitated by using virtual room displays for spatially organizing information inside of rooms, but additional design methods are needed to enhance between-room spatial knowledge. To evaluate its potential as a design enhancement, a prominent landmark in the hallway between the rooms was compared with a no landmark condition. Participants navigated a shopping center via hallways on a desktop virtual environment. Pointing and sketch map data were obtained as measures of configural (or survey) spatial knowledge for objects in the same store or in different stores. A robust "room effect" was found. Spatial knowledge was better for objects in the same store than for objects in different stores. However, the landmark had little or no effect on between-store spatial knowledge. These results suggest that landmarks may not be effective at enhancing the design of 3-D human-computer interfaces.
Developing Visualization Tools for the Design of Air Traffic Control Experiments BIBAFull-Text 1878-1881
  Chris G. Tsonis; Daniel C. Cunha; Jonathan M. Histon
While there has been significant research in the development of visualization tools for users of technology, little attention has been paid to developing visualization tools for human factors researchers designing experiments. From a design of experiments perspective, it is difficult to design video game-like experiments like those in found in air traffic control research, because of the need to control potential confounds such as consistency of scenarios and possible practice effects. When designing scenarios, the state and consistency of initial conditions can critically affect the experiment's outcome and validity. In this paper, we discuss several tools and techniques that were developed to better visualize these initial conditions and easily export them to the interface software. The key features of these tools are that they are relatively simple to develop, straightforward and fast to use, provide a graphical interface for the experiment designer, and ultimately can reduce the total design time for each experiment. Visualization tools based on the same general principles can also be of value in other domains.
Teleportation and Navigation in a 3-D Web-Based Virtual Shopping Environment BIBAFull-Text 1882-1886
  Tiffany N. Saffell; Herbert A. Colle
Using teleportation via a map menu icon instead of navigation from store to store via hallways was investigated in a web shopping simulation. Participants shopped in a virtual shopping center, examining and learning about various items. The simulation used HTML web pages that simulated a 3-D virtual environment. Half of the participants traveled from store to store using a map icon, which accurately depicted the shopping center. Clicking on a store in the icon teleported the perspective viewpoint to its doorway. Participants' configural (survey) spatial knowledge was tested using both sketch maps and pointing. No navigation mode differences were found with pointing angular error or sketch map angular error. These results indicate that teleportation via an iconic map did not improve spatial knowledge acquisition. However, it also did not impair it, while making navigation easier.

SURFACE TRANSPORTATION: Intersections, Teens, and Teens in Intersections

Rural Stop-Controlled Intersection Decision Support Systems BIBAFull-Text 1887-1891
  Jason Laberge; Nicholas Ward; Michael Rakauskas; Janet Creaser
Minnesota drivers are over-represented in accidents at rural stop-controlled intersections. There is also evidence that drivers in other states as well as older drivers are involved in many of these crashes. A task analysis and literature review showed that rural drivers could be getting into accidents because of problems detecting vehicles or gaps, perceiving or estimating the size of gaps, and/or judging gaps as safe. It is suggested that intersection decision support (IDS) systems present drivers with information elements that help them correctly identify and locate other vehicles and in some cases highlight (safe) gaps in approaching traffic. Several design concepts are proposed and research needs are discussed.
Effects of Haptic Brake Pulse Warnings on Driver Behavior During an Intersection Approach BIBAFull-Text 1892-1896
  Sarah B. Brown; Suzanne E. Lee; Miguel A. Perez; Zachary R. Doerzaph; Vicki L. Neale; Thomas A. Dingus
Intersection crashes account for nearly a quarter of all police reported crashes, and 39% of these result in injury or death. In this experiment, haptic warnings were explored as an alternative to auditory and visual warnings as part of an overall effort to reduce the number of intersection related crashes. The study objective was to determine the haptic brake pulse warning candidate that most often results in the driver successfully stopping for an intersection. Five candidate brake pulse warnings were tested; these varied with respect to length and number of pulses. Significant differences were found between haptic conditions for peak and constant deceleration. Participants receiving the haptic warning were 38 times more likely to stop than those receiving no warning.
Normal and Hard Braking Behavior at Stop Signs and Traffic Signals BIBAFull-Text 1897-1901
  Suzanne E. Lee; Sarah B. Brown; Miguel A. Perez; Zachary R. Doerzaph; Vicki L. Neale
A testbed intersection violation warning system was developed to address the problem of intersection crashes. The effectiveness of such systems is fundamentally dependent on the driver-braking model used to decide if a warning should be issued to the driver. If the model is unrealistic, drivers can either be annoyed due to assumed braking levels that are too low, or can be warned too late if braking expectations are too high. Initial algorithm development relied on data from the Collision Avoidance Metrics Partnership (CAMP) Forward Collision Warning (FCW) project. However, it was unknown whether the CAMP data (collected in the presence of stopped lead vehicles) would be applicable to the intersection problem (e.g., will drivers respond similarly to red traffic signals and stopped lead vehicles). Braking profile and performance tests were thus conducted to determine the applicability of the CAMP FCW results to the intersection violation warning.
The Effects of Teen Passengers on Teen Driver Speeds and Headways BIBAFull-Text 1902-1906
  Neil Lerner; Jeremiah Singer; Bruce Simons-Morton
This observational study investigated teen driving as a function of passenger presence and passenger gender. Vehicles were observed leaving high school parking lots at dismissal time, and the apparent age (teen or adult) and gender of drivers and passengers were recorded. At sites near the school, vehicle speeds and headways were recorded using a LIDAR and video-based system. Vehicles in the traffic stream were matched, where possible, to vehicles identified leaving the school. Thus, vehicles driven by teens could be distinguished from "general traffic." Passenger presence and gender had strong effects on speed and headway and were more pronounced than driver gender effects. While teens drove slightly faster than general traffic, the primary influence on speed was the presence of a male passenger. Similarly, shorter headways were associated with male, rather than female, passengers. Passenger influences on teen driving depend on passenger gender, driver gender, and the particular driving measure.
Intersection Behavior of Novice Teen Drivers and Experienced Adult Drivers BIBAFull-Text 1907-1911
  Erik C. B. Olsen; Bruce G. Simons-Morton; Suzanne E. Lee; Vicki L. Neale
Most unintentional deaths among 16-17 year olds are due to motor vehicle crashes; crash rates for teens are highest for novice teen drivers during the first six months and 1,000 miles after licensure. To date, no on-road research efforts have documented the initial deficits in driving skills for novice teen drivers and improvements with experience. In addition, few efforts have investigated the effects of in-vehicle tasks on driving performance for teens. To address this shortcoming, the performance of novice teen (licensed <1 month) and experienced adult drivers was investigated on a test track. Results for intersection tasks revealed that adults were more likely to stop for an amber light activated at various distances. When performing a cellular phone task while approaching an intersection, adults were more likely to notice and stop for the red light, and teens who did notice the red light were indecisive about how to respond.

SURFACE TRANSPORTATION: Internal and External Factors: Driver Impairment and Nighttime Driving

Behavioral Effects of Driver Distraction and Alcohol Impairment BIBAFull-Text 1912-1916
  Michael Rakauskas; Nicholas Ward
There remains some debate regarding secondary task distractions, such as cell phones, as a risk factor in traffic crashes and their relative risk compared to existing factors, such as engagement in common in-vehicle tasks and alcohol impairment. Moreover, studies of driver impairment often investigate single risk factors rather than combined factors (e.g. distraction task while drunk). This study compared non-distracted driving in a motion-based driving simulator to distracted driving (hands-free cell phone conversations, common in-vehicle tasks) either while sober or combined with alcohol (BAC 0.08). The results indicated that during a car following scenario, drivers engaged in the conversations or completing in-vehicle tasks were more impaired than drivers that were not involved in any distraction task. Indeed, both the cell phone and in-vehicle sources of distraction were generally more impairing than intoxication at the legal limit.
Leading Indicators of Drowsiness in Simulated Driving BIBAFull-Text 1917-1921
  Ksenia Kozak; Reates Curry; Jeff Greenberg; Bruce Artz; Mike Blommer; Larry Cathey
Drowsiness while driving was measured using three measures: a physiological measure of eye closure, a sustained reaction time task and a subjective assessment. The study was conducted in Ford's VIRTTEX driving simulator. Thirty-two adults who were sleep deprived for 24 hours and six adults who had a full night of sleep participated in the study. The performance of the sleep-deprived group was compared with that of the control group. Sleep-deprived drivers had significantly longer PVT reaction times, a greater number of lapses, higher PERCLOS values and perceived themselves as sleepier than did the control group. This study demonstrated the ability to successfully implement drowsiness measures in a driving simulator. The advantage of a three-hour simulator drive in providing increasing levels of drowsiness in each subject was established. These findings provide metrics that can be used to evaluate the efficacy and acceptability of safety systems for drowsy drivers.
Driver Inattention: A Contributing Factor to Crashes and Near-Crashes BIBAFull-Text 1922-1926
  Sheila G. Klauer; Vicki L. Neale; Thomas A. Dingus; David Ramsey; Jeremy Sudweeks
Driver distraction, or inattention, has been receiving wide media attention recently as many state legislatures are considering various levels of restricting cell phone use. Research has been conducted using a variety of experimental methods to determine the level of risk associated with driving inattention. While most of this research suggests that inattention impairs driving, there have been no studies to directly link driving inattention to crashes. Data from the 100-Car Naturalistic Driving Study, an instrumented vehicle study for which data was collected on 100 drivers in the Washington, DC metropolitan area for 12 months, were used in the following analyses. Crashes and near-crashes were identified in the data using post-hoc triggers based upon driving performance metrics, (i.e. hard braking). Results suggest that inattention contributed to 78% of all crashes collected over the 12 month data collection period.
Effects of Driving Speed and Sign Reflectance on Nighttime Highway Sign Legibility Distance and Reading Time Requirements BIBAFull-Text 1927-1930
  Frank Schieber
Nighttime highway sign legibility distance was evaluated as drivers maintained speeds of 5 versus 60 MPH. Effective legibility distance fell by approximately 30% when driving at high speed (114.9 versus 81.2 m at 5 and 60 MPH, respectively; F(1,9) = 48.6, p < 0.001). This finding suggests that past research, usually conducted under static viewing conditions (i.e., less than 5 MPH), probably overestimates the distance at which drivers can effectively read signs at night. In order to evaluate the appropriateness of new minimum sign reflectance levels proposed by the Federal Highway Administration (FHWA), legibility distance was also evaluated using 100% (new) versus 15% reflectance signs. Results indicate that nighttime legibility distance can be expected to fall by approximately 12% over the life cycle of a microprismatic retroreflective highway sign given the proposed FHWA minimum reflectance specification (104.2 versus 91.9 m for 100% and 15% reflectance, respectively; F(1,9) = 20.6, p < 0.001).
Size Isn't Everything: The Effects of Size and Brightness of Retroreflective Materials on Nighttime Conspicuity BIBAFull-Text 1931-1934
  Paul E. Cassidy; Brian E. Brooks; Nathan J. Anderson
To increase their level of conspicuity, emergency response personnel wear Personal Protective Equipment (PPE) with retroreflective materials. That is, retroreflective materials increase the probability that oncoming motorists will see them. The goal of the current study was to provide empirical evidence regarding the relative nighttime conspicuity of conventional-trim retroreflective patterned garments (which have retroreflective material concentrated on specific portions of the garment) and area-retroreflective patterned garments (which have retroreflective material distributed evenly across the surface area of the garments). The question of interest was whether trim and area-reflective garments that reflect the same amount of light (i.e., equal RI values) provide equivalent conspicuity. At night, subjects seated in the passenger seat of cars approaching a live simulated roadway accident scene attempted to detect and recognize a human form in the road. Across three different levels of RI, the results demonstrate that when area reflective and trim garments reflect the same overall amount of light, area reflective garments provide lower levels of conspicuity than do conventional trim garments. These results suggest that, under the conditions of the current study, the brightness per unit area of retroreflective material needs to be considered rather than simply considering the total brightness of the garment independent of the size of the retroreflective surface-area.

SURFACE TRANSPORTATION: About Driver Awareness Systems: "I'm a Good Driver; It's Everyone Else"

How much Clearance Drivers want while Parking: Data to Guide the Design of Parking Assistance Systems BIBAFull-Text 1935-1939
  Sujata Gadgil; Paul Green
This experiment examined how close to objects (such as a wall or another vehicle) people would drive when parking. The findings determined the distance at which visual and/or auditory warnings should be provided by parking assistance systems.
   Sixteen drivers (8 aged 18-30, 8 over age 65) served as subjects. Data was collected for the subject sitting in the driver's seat of a 2004 Nissan Q45 (a full-size sedan) and when they were outside the vehicle (as if directing someone else to park). Data was collected for moving a simulated brick wall towards and away from the test vehicle for 8 cardinal clock positions.
   The overall mean distance was 20.4 in for the 640 data points collected, ranging from 2.5 to 48.5 in. Using the regression method, 1 of the 2 developed methods, the desired distance (in) was equal to 9.5 + 1.6 (if the position was to the side or rear) + 6.7 (if a door was to be opened) + 5.7 (if the object was approaching the car) + 4.9 (if the driver's clearance was estimated) + .07 times the driver's age.