HCI Bibliography Home | HCI Conferences | HFES Archive | Detailed Records | RefWorks | EndNote | Hide Abstracts
HFES Tables of Contents: 000102030405060708091011121314

Proceedings of the Human Factors and Ergonomics Society 48th Annual Meeting 2004-09-20

Fullname:Proceedings of the Human Factors and Ergonomics Society 48th Annual Meeting
Location:New Orleans, Louisiana
Dates:2004-Sep-20 to 2004-Sep-24
Standard No:ISBN: 0-945289-24-3; hcibib: HFES04; TA 166 H794
Links:Online Proceedings | Online Order Form
  1. HFES 2004-09-20 Volume 48
    1. AEROSPACE SYSTEMS: Advanced Displays
    2. AEROSPACE SYSTEMS: Air Traffic Management and Control
    3. AEROSPACE SYSTEMS: Automation and Aids
    4. AEROSPACE SYSTEMS: Human Factors Engineering for Space Exploration Missions
    5. AEROSPACE SYSTEMS: Human Factors Issues in Synthetic Vision Displays: Government, Academic, Military, and Industry Perspectives
    6. AEROSPACE SYSTEMS: Measures
    7. AEROSPACE SYSTEMS: Methods and Models
    8. AEROSPACE SYSTEMS: Multimodal Displays and Virtual Environments
    10. AEROSPACE SYSTEMS: Synthetic Vision
    11. AGING: Aging General Session
    12. AGING: Posters
    13. AGING: Technology Aids for Aging
    14. COGNITIVE ENGINEERING AND DECISION MAKING: Task Planning, Interruptions, and Situation Awareness
    15. COGNITIVE ENGINEERING AND DECISION MAKING: Applying Cognitive Engineering to Meteorological Forecasting
    16. COGNITIVE ENGINEERING AND DECISION MAKING: Aviation Systems and Displays
    17. COGNITIVE ENGINEERING AND DECISION MAKING: Brunswik's Lens Model in HF Research: Modern Applications of a Classic Theory
    18. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Factors in Intelligence Analysis
    19. COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Modeling and Interface Design
    20. COGNITIVE ENGINEERING AND DECISION MAKING: Designing Support for Intelligence Analysis
    21. COGNITIVE ENGINEERING AND DECISION MAKING: Displays and Interface Design
    22. COGNITIVE ENGINEERING AND DECISION MAKING: Error Analysis and Decision Quality
    23. COGNITIVE ENGINEERING AND DECISION MAKING: Expertise and Macrocognition Analysis
    24. COGNITIVE ENGINEERING AND DECISION MAKING: Exploration in Cognitive Work Analysis
    25. COGNITIVE ENGINEERING AND DECISION MAKING: Factors and Analysis in Command and Control
    26. COGNITIVE ENGINEERING AND DECISION MAKING: Human Control of Teams of Robotic Vehicles: Exploring the Limits of the Possible
    27. COGNITIVE ENGINEERING AND DECISION MAKING: Information Overload, Data Fusion, and EID
    30. COGNITIVE ENGINEERING AND DECISION MAKING: Team Cognition in Multirobot Control
    31. COGNITIVE ENGINEERING AND DECISION MAKING: Tightening the Linkage of CSE and Software Systems Engineering
    33. COMMUNICATIONS: Phones, Videoconferences and Automated Speech Systems
    34. COMMUNICATIONS: Poster
    35. COMPUTER SYSTEMS: Displays, Auditory and Visual
    36. COMPUTER SYSTEMS: Input for Handheld Devices
    37. COMPUTER SYSTEMS: Interfaces: Making Them Work
    38. COMPUTER SYSTEMS: Mouse Design and Use
    39. COMPUTER SYSTEMS: Navigation and Feedback
    40. COMPUTER SYSTEMS: Posters
    41. COMPUTER SYSTEMS: Systems and Usability
    42. CONSUMER PRODUCTS: Issues in Usability
    43. CONSUMER PRODUCTS: Methods in Product Development and Evaluation
    44. CONSUMER PRODUCTS: Posters
    45. CONSUMER PRODUCTS: Product Development and Annual PDTG Product Award
    46. EDUCATION: Education Tools
    47. EDUCATION: How Do You Teach HF to Colleagues at Work?
    48. EDUCATION: Posters
    49. EDUCATION: Potpourri
    50. EDUCATION: Team Behavior -- Its Use for Human Factors Professionals
    51. ENVIRONMENTAL DESIGN: Environmental Design at the Office
    53. ENVIRONMENTAL DESIGN: Universal Design
    54. FORENSICS PROFESSIONAL: A Two-Way Street -- With Hazards: Expert/Attorney Communications
    55. FORENSICS PROFESSIONAL: Forensic Research
    56. FORENSICS PROFESSIONAL: The Forensics Human Factors Consultant
    57. GENERAL SESSION: Augmented Cognition
    58. GENERAL SESSION: Lessons Learned
    59. GENERAL SESSION: New Practices in Human Factors
    60. GENERAL SESSION: Posters
    61. GENERAL SESSION: Virtual Reality Simulators in Medicine: Current and Future Concerns
    65. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Stress Effects on Soldier Performance
    66. INDUSTRIAL ERGONOMICS: Electromyography/Upper Extremity
    67. INDUSTRIAL ERGONOMICS: Hand Force and Posture
    68. INDUSTRIAL ERGONOMICS: Implications of Dynamic Touch for Human Factors/Ergonomics
    70. INDUSTRIAL ERGONOMICS: Practice-Oriented Session
    71. INDUSTRIAL ERGONOMICS: Psychosocial
    72. INDUSTRIAL ERGONOMICS: Quantification of Exposure
    73. INDUSTRIAL ERGONOMICS: Slips and Falls/Aging
    74. INDUSTRIAL ERGONOMICS: Upper Extremity
    75. INTERNET: Applications
    76. INTERNET: E-Commerce
    77. INTERNET: Finding Information Online
    78. INTERNET: Posters
    79. MACROERGONOMICS: Macroergonomics: Analysis, Technology, and Quality of Worklife
    80. MACROERGONOMICS: Macroergonomics: Approaches and Interventions
    81. MACROERGONOMICS: Posters
    82. MACROERGONOMICS: Macroergonomics in Health Care
    83. MEDICAL SYSTEMS AND REHABILITATION: Analysis and Decision Support in Medical Systems
    84. MEDICAL SYSTEMS AND REHABILITATION: Human Factors and Safety in Medical Systems: Where Have We Reached? Where Should We Go?
    85. MEDICAL SYSTEMS AND REHABILITATION: Medical Systems and Rehabilitation
    86. MEDICAL SYSTEMS AND REHABILITATION: Migration of Medical Devices from Clinical to Home Care
    87. MEDICAL SYSTEMS AND REHABILITATION: Performance Issues in Medical Applications
    89. MEDICAL SYSTEMS AND REHABILITATION: Psychological and Physical Issues in the Clinical Environment
    90. MEDICAL SYSTEMS AND REHABILITATION: Role of Human Factors in Health Care 2020
    91. MEDICAL SYSTEMS AND REHABILITATION: Usability and Assistive Technology in Health Care
    93. PERCEPTION AND PERFORMANCE: Auditory Displays and Sonification
    94. PERCEPTION AND PERFORMANCE: Menus, Icons, and Visual Search
    95. PERCEPTION AND PERFORMANCE: Perception & Psychophysics
    97. PERCEPTION AND PERFORMANCE: Speed Perception, Spatial Reference Systems, and Vigilance
    98. PERCEPTION AND PERFORMANCE: Workload and Performance
    99. PERCEPTION AND PERFORMANCE: Components of Adverse Events: Examples in Multiple Contexts
    100. PERCEPTION AND PERFORMANCE: Development, Status, and Implications of ANSI Z535.6
    102. PERCEPTION AND PERFORMANCE: Safety and Communication
    103. PERCEPTION AND PERFORMANCE: Safety Relationships and Methods
    104. SPECIAL SESSION: Afterwords: The Quality of Medical Accident Investigations and Analyses
    105. SPECIAL SESSION: Analysis and Design Demonstrations
    106. SPECIAL SESSION: Cognitive Human Performance Modeling
    107. SPECIAL SESSION: Virtual Humans and Virtual Environments
    108. STUDENT FORUM: Cutting-Edge Research by Students I
    109. STUDENT FORUM: Cutting-Edge Research by Students II
    110. STUDENT FORUM: Cutting-Edge Research by Students III
    111. STUDENT FORUM: Launching Your Career in HF/E: Guidelines for Soaring High in the Job Market
    112. STUDENT FORUM: Posters
    113. SURFACE TRANSPORTATION: Drive Now, Talk Later? Driving Issues With In-Vehicle Cell Phone Use
    114. SURFACE TRANSPORTATION: Collision Avoidance Systems: Intersection of Man and Machine
    115. SURFACE TRANSPORTATION: Critical Issues in Driving Simulation Methods & Measures
    116. SURFACE TRANSPORTATION: New Designs, New Drivers
    118. SURFACE TRANSPORTATION: Psychophysiology in Driving Research
    119. SURFACE TRANSPORTATION: Teen Drivers, Education, and Licensing
    120. SURFACE TRANSPORTATION: Watch Out! Issues in Driver Distraction and Situational Awareness
    121. SYSTEM DEVELOPMENT: Posters
    122. SYSTEM DEVELOPMENT: System Development Applications
    123. TEST AND EVALUATION: Methodology I
    124. TEST AND EVALUATION: Methodology II
    125. TEST AND EVALUATION: Posters
    126. TEST AND EVALUATION: Potpourri
    127. TRAINING: Extending and Incorporating Approaches from Traditional Intelligent Tutoring Systems into Scenario-Based Training Systems
    128. TRAINING: Human Learning and Performance in Training Research
    129. TRAINING: Improving Distributed Simulation-Based Training
    130. TRAINING: Posters
    132. VIRTUAL ENVIRONMENTS: Virtual Environments I
    133. VIRTUAL ENVIRONMENTS: Virtual Environments II

HFES 2004-09-20 Volume 48

AEROSPACE SYSTEMS: Advanced Displays

The Effect of Functional Information in an Avionics Display BIBAFull-Text 1-5
  Carl F. Smith; Deborah A. Boehm-Davis; Ronald Chong
Allowing pilots to directly perceive the functional properties of flight may improve piloting performance. This study examines differences in piloting performance between a flight display (OZ) that displays a functional relationship between power and airspeed and a conventional Cessna display. Eight pilots performed flight maneuvers on a fixed base flight simulator over six trials per display. Pilots' performance with the functional display (OZ) showed greater control of power and reduced individual differences. The role of functional information and its implementation in future aviation displays are discussed.
A Visual Display of Flight Time and Distance BIBAFull-Text 6-10
  Roshanak M. Nadimian; Catherine M. Burns
A flight simulation study was conducted to examine the effect of a visual display of flight time and distance added to a pathway prediction symbology on pilot's flight time management. Twelve participants flew a standard flight path with a time-constrained landing task. Some conditions such as flight under various wind and visibility levels, or instrumentation failures were also applied to the flight tests to measure performance in more challenging conditions. We measured flight's time error as our measure in this study. The results showed that participants flew more accurate flights and landed closer to the required landing time with the visual display particularly under challenging conditions. We concluded that the enhancements made to the pathway prediction display by adding the time-distance gauge supported improved flight time management and flight control.
Comparison of Head-Up and Head-Down Highway-in-the-Sky Tunnel and Guidance Concepts for Synthetic Vision Displays BIBFull-Text 11-15
  Lawrence J. Prinzel; Lynda J. Kramer; Jarvis J. Arthur; Randall E. Bailey; Raymond J. Comstock
HUD Use Improves Landing Performance in a Full-Motion Simulator BIBAFull-Text 16-20
  Orjan Goteman; Kip Smith; Sidney Dekker
The operational community has assumed that using a head-up display (HUD) rather than conventional head-down displays will increase safety margins in approach and landing operations. This paper discusses a pair of experiments that test that hypothesis. Using a Boeing 737-700 full-motion simulator and commercial airline pilots as subjects, we explored the effects of (1) HUD use, (2) ambient visibility, and (3) length of approach lighting on the size and location of the touchdown footprint. HUD use reduced the width of the touchdown footprint in all tested visibility and lighting conditions including visibility below the minimum allowed. HUD use had no effect on the length of the touchdown footprint. These are empirical data that could inform the writing of regulations regarding HUD-supported commercial aviation operations.
Evaluating the Utility of a Multi-layer Visual Display for Air Battle Managers BIBAFull-Text 21-25
  Robert S. Bolia; W. Todd Nelson; Matthew S. Middendorf; Nicole M. Guilliams; Annie B. McLaughlin
Air Battle Managers in the United States Air Force must continually monitor a situation display (SD) in addition to performing a number of secondary tasks, which typically occlude part or all of the SD. The purpose of the present investigation was to determine whether the use of a multi-layer display, on which visual information is presented at two different depths, with varying degrees of transparency, would reduce the performance decrement associated with concurrent task performance by eliminating the effects of occlusion. A multi-element tracking task was employed as an analogy to the SD, while a cognitive vigilance task was used to represent the additional visual task. Analyses suggest that transparency effects may play a role in reducing the deficits introduced by occlusion, and may also reduce perceived mental workload. However, despite the findings of previous research, there was no significant effect of depth.

AEROSPACE SYSTEMS: Air Traffic Management and Control

EFfects of Air Traffic Geometry on Pilots' Conflict Detection with Cockpit Display of Traffic Information BIBAFull-Text 26-30
  Xidong Xu; Christopher D. Wickens; Esa M. Rantanen
We explored the effects of conflict geometry on pilot conflict understanding, manifested in estimation accuracy of three continuous variables: miss distance, time to closest point of approach, and orientation at the closest point of approach. Results indicated (a) increased difficulty of understanding with conflicts that occurred with slower speeds, a longer time into the future, and a longer distance into the future; (b) a tendency for pilots' judgments often to be conservative, judging that conflicts were both more risky and would occur sooner than was actually the case; and (c) a "distance-over-speed" bias, such that two aircraft viewed farther apart and converging rapidly were perceived as less risky than two aircraft that were closer to each other and converging at a slower rate, even though the time until a conflict occurred was identical.
Pilot Use of a Cockpit Display of Traffic Information During Aircraft Navigation on the Airport Surface: An Analysis of PilotController Operational Communication BIBAFull-Text 31-35
  O. Veronika Prinzo
The Federal Aviation Administration is making a concerted effort to reduce runway incursions. A 5-day operational evaluation conducted in October 2000 assessed pilot use of varying types of CDTI devices. Structured and unstructured taxi routes examined how well pilots navigated their aircraft using electronic surface-map displays (north-up, track-up) or a paper surface map. An analysis was performed of 15 hours of communication data to determine how the use of these displays might aid situation awareness and influence operational communications. A Type-of-Route x Type-of-Map ANOVA revealed that more problems occurred, and more messages were exchanged for structured taxi routes. Most problems occurred for the north-up group during structured taxi routes, and the number of problems encountered was comparable for the other map groups when pilots navigated unstructured taxi routes. The format in which a map is presented appears to affect some aspects of pilot performance during airport surface navigation.
Experimental Investigation of Predictive Probabilistic and Temporal Conflict Avoidance Displays BIBAFull-Text 36-40
  Jason Telner; Milgram Paul; Alexander R. Williamson
Inferring the future intentions and courses of aircraft or ships at various points in time can be problematic for traffic controllers. In this paper, a new graphical display concept is presented, comprising predictive information about the times, locations, and probabilities of potential traffic conflicts. Twelve participants engaged in a ship control conflict avoidance task. Results indicate that during the first block of experimental trials participants used significantly fewer manoeuvres to resolve potential conflicts and did so with better overall scores when using the new graphical display, as compared to the conventional format. However, during the second and third blocks of trials, performance did not significantly differ as a function of display condition. Nevertheless, subjective ratings strongly indicated participants' preferences for the new graphical format, suggesting that the new display format offers potential performance benefits for controllers of air and ship traffic.
Testing the Surface Management System (SMS) through Operational Trials with Air Traffic Control and Airline Participants BIBAFull-Text 41-45
  Lynne Martin; James M. Hitt; Sandra Lozito
The Surface Management System (SMS) aims to increase airport capacity and decrease surface gridlock, which are goals consistent with the Federal Aviation Administration's (FAA) National Airspace System Operational Evolution Plan (FAA, 2002). An operational trial was conducted to evaluate the initial design of the SMS traffic management tools. Although the dataset was small, participant responses were positive on four dimensions (usefulness, frequency of use, perceived accuracy, and ease of use) for nearly all of the six traffic management tools. Participant debriefs highlighted additional issues including the effects of SMS on coordination between Air Traffic Management facilities. This paper outlines the conduct of the operational trials and explores two of the major issues raised by the observations made during the trials.
Improving the Usability of an Automated Tool for the Recording, Coordination, and Communication of Traffic Management Initiatives BIBAFull-Text 46-50
  Bart Brickman; Tanya Yuditsky
The current processes for recording, coordinating, and communicating traffic management initiatives in Air Traffic Control (ATC) are inefficient, workload intensive, and time consuming. The National Traffic Management Log (NTML) is an automated tool that will enhance and streamline these processes. We used an iterative design methodology with a multidisciplinary design team to develop solutions to existing design problems, and to design new system capabilities. The design team included Human Factors specialists, hardware and software engineers, and ATC domain experts. The design challenges faced by the team included addressing the unique needs of the various ATC domains while providing a usable human-computer interface. The application of the iterative design methodology and the benefits of using a multidisciplinary design team will be discussed.

AEROSPACE SYSTEMS: Automation and Aids

GPS Outage En-Route Simulation BIBAFull-Text 51-55
  Nicole S. Racine; Edmundo A. Sierra; Karen Buondonno
This study was an initial examination of controllers' ability to manage Global Positioning System outage situations caused by intentional/unintentional radio frequency interference. Twenty-seven certified professional air traffic controllers staffed their on-the-job sectors that were emulated on a high fidelity platform. Three navigational system outage conditions were simulated: no outage, partial outage, and full outage. Three operational environments were also simulated: a current environment, a future avionics equipage environment, and a future avionics equipage environment with ground based navigation aid reductions. The research team collected coordination, task effectiveness measures, and real-time subjective workload ratings. Results indicated the controllers had significant increases in workload and coordination activities due to outages; however, no differences in task effectiveness measures emerged. The overall conclusion made in this study is that although there was a significant effect of outage on workload, controllers were generally able to compensate for the increase. The operational environment was inconsequential.
Supporting Taxiing for General Aviation Pilots through Dynamic Message Signs: Simulation Evaluation and Implications for the Prevention of Runway Incursions BIBAFull-Text 56-60
  Peter M. Moertl; Gregory Niehus; Kathleen McGarry; Nicole S. Racine; Raja Parasuraman; Albert Rehmann
The potential of dynamic message signs to update pilots' expectations about airport surface characteristics was investigated in a simulation experiment. Signs were placed at simulated high-hazard airport intersections to inform pilots about uncommon surface characteristics and it was investigated if and how general aviation pilots could use such signs to update their expectations during taxiing. The results of the simulation study indicate that about two thirds of the pilots without prior experience with dynamic message signs noticed and processed the sign information. About two thirds of those pilots adjusted their taxiing according to the sign information. On average, pilots who were more likely to notice the message sign also reported higher levels of situation awareness (Taylor 1990) than pilots who were less likely to notice the sign. It was found that dynamic message signs did not reduce the risk of violating hold-short instructions if pilots were not familiar with the dynamic message signs. Specific procedural and standardization recommendations are given to improve sign benefits.
Adaptability and Flexibility are Key Benefits of the Playbook Interface for Human Supervision of Multiple Unmanned Vehicles BIBAFull-Text 61-65
  Peter Squire; Hiroshi Furukawa; Scott Galster; Christopher Miller; Raja Parasuraman
There is increasing empirical evidence supporting the "Playbook" interface as an effective method for controlling multiple unmanned vehicles (UVs). To better understand the benefits provided by a flexible Playbook interface, participants controlled either four or eight robots in a simulated UV mission with different forms of restricted or flexible Playbook interfaces in the Roboflag environment. Level of abstraction (robot behavior) and level of aggregation (unit of robot selection) were manipulated to yield different restricted or flexible interfaces. The results confirmed the benefits provided by a flexible Playbook interface in which operators are empowered to delegate (or not) tasks to automated agents, compared to less flexible interfaces which are susceptible to negative effects due to suboptimal automation or unexpected events.
Command and Telemetry Latency Effects on Operator Performance during International Space Station Robotic Operations BIBAFull-Text 66-70
  Nancy J. Currie; Jennifer Rochlis
International Space Station operations require onboard crewmembers to perform numerous robotic assembly, maintenance, and inspection activities. Ground-based control of the Mobile Servicing System (MSS), in particular the Special Purpose Dexterous Manipulator (SPDM), has been identified as one potential solution to alleviate disproportionate robotic maintenance and inspection timelines that potentially exceed crew availability and duty times. Challenges to operator performance and safety of ground-based control of these manipulators include significant data and telemetry latency. Recent trends of transmissions between the International Space Station and NASA's Mission Control Center have determined the round-trip time delay can range from 6-8 seconds. The purpose of this study was to examine operator performance when subjects performed representative dexterous robotic tasks with anticipated command and telemetry time delays. Results from this study may determine whether augmentations to existing operator tools and procedures are required in order to manually control the SPDM from ground-based workstations.

AEROSPACE SYSTEMS: Human Factors Engineering for Space Exploration Missions

Human Factors Engineering for Space Exploration Missions BIBAFull-Text 71-74
  Brian Peacock; Jeffrey McCandless; Sudhakar Rajulu; Frances Mount; Melissa Mallis; Mihriban Whitmore; Cynthia Null
NASA now has a focused mission for space exploration. We will continue to use ground based analogs and simulators, the Space Shuttle and the International Space Station as research and development platforms, but the challenges of time, distance and very hostile environments raise the challenges to human factors engineering designers to an even greater level. We will have a new generation of vehicles, equipment, habitats and space suits; operations and activity management will present novel scheduling, training and task allocation opportunities. The safety stakes will also be higher and the cold euphemisms of risk management will require some humanization, both for the crew and the public.
   Space vehicle launch, docking, navigation and landing will require complex interactions between automation and human operators. Commanders and pilots will require considerable simulator training and will be expected to perform flawlessly despite the debilitating exposure to extended time in space. Physical tasks on planetary surfaces will require protective suits that allow explorers to function effectively without the risk of excessive fatigue. Deviations from our familiar 24 hour day night cycle will demand innovative countermeasures if crew members are not to succumb to performance decrements due to cumulative sleep deprivation. Operation of complex life support, transportation, emergency response and scientific systems will require the development of effective and efficient job aids and procedures. Planetary surface habitats will be designed with the life support systems and home comforts necessary for long duration tenure. Finally, the safety of the human crew will be paramount and will require robust hybrid human-robotic systems, activity schedules and operations management.
   The NASA space human factors community is addressing these challenges by observing the performance of crew members in analogs, simulators and real missions and supporting this activity by basic and applied research in NASA laboratories and in collaboration with external scientists. The presentations in this panel will describe some of the current efforts to support this focused NASA exploration mission.

AEROSPACE SYSTEMS: Human Factors Issues in Synthetic Vision Displays: Government, Academic, Military, and Industry Perspectives

Human Factors Issues in Synthetic Vision Displays: Government, Academic, Military, and Industry Perspectives BIBAFull-Text 75-79
  Lawrence J. Prinzel; J. Raymond Comstock; Tim Etherington; Guy A. French; Michael P. Snow; Mica R. Endsley; Christopher D. Wickens; Kevin M. Corker
Aviation has been witness to rapid advancement in technologies that have significantly improved aviation safety. The development of attitude indicators, flight management systems, radio navigation aids, and instrument landing systems (ILS) have extended aircraft operations into weather conditions with reduced forward visibility. However, as Brooks (1997) has noted, "...while standard instrumentation has served us well, enabling aviation as we see it today, literally thousands of dead souls, victims of aviation catastrophe, offer mute and poignant testimony to its imperfections. The simple, elegant dream of soaring aloft visually, intuitively -- bird-like -- remain elusive" (p. 17). Using conventional displays, pilots must integrate information from many separate sources to achieve situation awareness. This integration process can lead to errors, which in some cases can have deadly consequences.


Development of Novel Measures to Assess the Effectiveness of Commercial Airline Pilot Situation Awareness Training BIBAFull-Text 80-84
  Simon Banbury; Helen Dudfield; Hans-Jurgen Hormann
The present study took a novel approach to the assessment of a commercial airline pilot Situation Awareness (SA) training programme developed under the European Commission Framework V ESSAI project. Two measures of SA were developed specifically for the present study; the Situation Awareness Knowledge Test (SAKT) and the Situation Awareness and Workload In-flight Measure (SAWIM). Thirty-two aircrew participants took part in this study; half received standard Line-Oriented Flight Training (LOFT) and half received the bespoke ESSAI SA training. The results of the study provide evidence for the validity of these tools to detect improvements to aircrew SA afforded by the novel training programme.
Effects of Task Demand and Time-on-Task on Psychophysiological Candidates for Biocybernetic Control BIBAFull-Text 85-89
  Stephen H. Fairclough; Louise Venables
Biocybernetic control refers the use of psychophysiology as a real-time input to a computerised system. Psychophysiology may be used to monitor relevant variables such as subjective mental workload in order to drive the control of adaptive automation. This study was concerned with the sensitivity and diagnosticity of psychophysiological measures to subjective mental workload and time-on-task. Thirty participants performed the Multi-Attribute Test Battery (MATB) for a period of sixty-four minutes. The results revealed an augmentation of Θ in conjunction with a suppression of α activity from parietal sites in response to high workload. In addition, heart rate, vagal tone and blink duration were sensitive to mental workload. The implications for the selection of psychophysiological variables for biocybernetic control are discussed.
Establishing the Psychophysiological Variables that can Identify and Predict Operator Subjective State BIBAFull-Text 90-94
  Louise Venables; Stephen H. Fairclough
Biocybernetic adaptation describes a system wherein automation is regulated by the operator's physiology. The identification of real-time psychophysiological variables capable of detecting and predicting operator subjective states is an important requisite for biocybernetic control. The present study investigated how psychophysiology may index negative subjective states, namely, task-disengagement, distress and worry.
   To encourage negative states, 35 participants performed the (high demand) Multi-Attribute Task Battery (MATB), for 100 minutes in total. Subjective state was assessed using the Dundee Stress State Questionnaire (DSSQ). The psychophysiological measures recorded included: GSR, EOG, EEG, ECG, and respiration. Analysis of the data revealed performance was sustained throughout the task although subjective states became more negative over time. This was accompanied by various psychophysiological changes, e.g. increased respiration rate. Regression analyses indicated that psychophysiological changes were predictive of changes in subjective states. The results and implications for biocybernetic systems are discussed.
Psychophysiologically Determined Classification of Cognitive Activity BIBAFull-Text 95-98
  Glenn F. Wilson; Christopher A. Russell
Psychophysiological measures and artificial neural networks were used to determine how well higher levels of cognitive activity, such as executive function, spatial and verbal working memory and global workload, could be assessed. A complex uninhabited air vehicle simulator was used in which subjects were responsible for four vehicles simultaneously. The subjects had to evaluate visual images and maintain the status of the vehicles. The results showed that the cognitive states, derived from subjective reports, could be accurately classified. These results have application in human factors environments which demand higher level cognitive processing and may be useful when implementing adaptive aiding in these systems.

AEROSPACE SYSTEMS: Methods and Models

Using Cognitive Modeling to Understand Crew Behavior BIBAFull-Text 99-103
  Deborah A. Boehm-Davis; Robert W. Holt; Ronald Chong; Jeffrey T. Hansberger
The ACT-R cognitive architecture has been used successfully to model aviation crew performance during the descent phase of flight. This study extended that approach by simulating the duties of a pilot flying (PF) and Pilot Not Flying (PNF) in separate ACT-R models which then were run jointly across several executions. For each set of executions, level of expertise and taskload of the PF and PNF were varied. The models were further tested by implementing interruptions through Air Traffic Control (ATC) calls. The results showed that both expertise and taskload affected performance. Further, ATC interruptions produced crew miscommunication, differential situation awareness, and forgetting relevant goals.
Goms on the Flight Deck: A Case Study of the Boeing 777 Mcp BIBAFull-Text 104-107
  Luis Ricardo Prada; Deborah A. Boehm-Davis
Despite the extensive literature available on GOMS methods for predicting task performance, there are relatively few hands-on examples of GOMS being used in an applied setting. This proof-of-concept paper will describe the use of CPM-GOMS and NGOMSL, in combination with an existing RAFIV, to evaluate the Boeing 777 autoflight system.
Examining New Flight Deck Technology using Human Performance Modeling BIBAFull-Text 108-112
  Stephen Deutsch; Richard Pew
Aircraft flight deck synthetic vision systems (SVS) always provide a "clear day" view and hence have the potential to improve safety in commercial aviation. Approach, landing, and taxi operations will most readily profit from the SVS capabilities. A part-task simulation study provided data on pilot performance using a baseline and an SVS-equipped flight deck. One effect of adding the separate SVS to the flight deck was that pilot scan patterns changed significantly -- more time was devoted to the attitude displays and less to the navigation display. Concern over the change in well-established scan patterns lead to the suggestion that the SVS, an attitude display, be combined with the primary flight display as a single Enhanced-SVS attitude display rather than augment it as a separate display. A human performance model study was used to reproduce the results of the part-task study and then establish that the Enhanced-SVS attitude instrument would restore the original pilot scan pattern.
Temporal Effects in Aircraft Inspection: What Price Vigilance Research BIBAFull-Text 113-117
  Colin G. Drury; Monique Saran; John L. Schultz
This paper examines issues of fatigue in inspection by using an established function analysis of inspection to show its characteristics, and then proposing a four-level classification of temporal effects to help future applications. This classification divides the temporal effects into four components: weekly, daily, hourly, and minute time scales. The analysis presented here will form the basis for the design of future experimental studies of temporal factors in aircraft inspection.
Experiments on Language Errors in Aviation Maintenance BIBAFull-Text 118-122
  Colin G. Drury; Jiao Ma
The Federal Aviation Administration has raised many issues concerning the outsourcing of maintenance to foreign repair stations and recommends establishing a method for determining whether language barriers result in maintenance deficiencies. This work addresses concerns that non-native English speakers may be prone to an increased error rate that could potentially affect airworthiness. This paper presents Year 2 of the project. We used the seven scenarios of language error developed in Year 1 as the basis for our data collection effort to quantify the frequency of error. An intervention experiment has been designed and tested on two groups of participants: English-speaking maintenance personnel and Chinese speaking engineering graduate students. Neither is the final target group, but the methodology needed to be verified before on-site data collection. The analysis of the data from these two experiments is presented here.

AEROSPACE SYSTEMS: Multimodal Displays and Virtual Environments

Comparing Pilot Training Performance in Immersive and Non-Immersive Virtual Environments BIBAFull-Text 123-126
  Celestine A. Ntuen; Kaize Adams; Peter M. Crane
This research investigated whether there was equal improvement for instrument pilot skill trained under an immersive virtual environment (IVE) versus a nonimmersive virtual environment (NIVE). In the IVE, sensory input to the human from external world is provided by head mounted displays, while NIVEs are represented by desktop displays. Subjects were tested in IVE and NIVE flight scenarios using three flying tasks -- normal crosswind approach and landing (NCAL), go-around (GA) and constant speed during climbing and descending (CSCD). Error rate data were analyzed for four pilot control tasks. The results show that NIVE provides error rate reduction for training altitude control under NCAL and GA tasks, and vertical speed control for CSCD. No significant differences were observed for both NIVE and IVE for vertical speed control. IVE showed error rate decrements for the rest of the tasks.
Comparison of Two Voice Synthesis Systems as to Speech Intelligibility in Aircraft Cockpit Engine Noise BIBAFull-Text 127-131
  Jeff A. Lancaster; Gary S. Robinson; John G. Casali
Empirical studies comparing newer text-to-speech (TTS) synthesis systems to older systems are lacking. This study compared two speech synthesizers, DECtalk 'Perfect Paul,' one of the most popular 'older' synthesizers, and a 'newer' synthesizer, AT&T's Natural Voices 'Mike,' for intelligibility utilizing the Modified Rhyme Test (MRT). Each system was evaluated at three speech-to-noise (S/N) ratios: -5 dB, -8 dB, and -11 dB, in a within-subjects design. Aircraft engine noise at 85 dB(A), produced by a Cessna 172R flight simulator, served as background noise. Normal hearing non-pilots served as subjects. Results indicated differences in intelligibility between the two speech synthesizers at each speech-to-noise ratio, with the AT&T product showing significantly better intelligibility than the DECtalk product. Potential applications of this research include guidance for the integration of automated voice technologies in the cockpit and in similar systems that present elevated levels of background noise during normal communications and auditory display operations.
The Effect of Audio Attitude Symbology on Unusual Attitude Recovery for General Aviation Pilots BIBAFull-Text 132-136
  Kristen K. Liggett; Peter Venero; Martin N. Anesgart
Eight general aviation pilots participated in a series of unusual attitude recovery tasks to determine the effect of the addition of audio symbology to visual symbology on performance. Two audio symbology sets were tested including a non-localized set of recovery commands, and a set of localized "fly-to" cues. Results showed that there was no significant difference in performance among the visual only condition, the visual plus non-localized audio commands, and the visual plus localized cues. There were, however, significant differences in performance based on the initial climb/dive angle condition of the unusual attitudes.
Tactile Versus Aural Redundant Alert Cues for Uav Control Applications BIBAFull-Text 137-141
  Gloria L. Calhoun; John V. Fontejon; Mark H. Draper; Heath A. Ruff; Brian J. Guilfoos
In complex UAV control stations, it is important to alert operators to actionable information in a timely manner. Tactile displays may alleviate visual workload by transmitting information through the skin, cueing operators to high priority, unexpected events. The utility of tactile alerts (vibration on wrists) in substitution for aural alerts, as a redundant cue to visual alerts, was examined. Participants responded to critical events alerted with aural or tactile redundant cues, while performing multiple tasks in a simulated UAV control station. Results showed that there were no significant performance differences between the conditions employing unique aural and tactile cues. These data suggest that the non-visual alerts may be equally compelling and the tactile alerts can substitute for aural alerts as a redundant cue to visual cues. Also, there was not a strong indication that tactile alerts were advantageous in a high noise environment. However, subjective comments and trends in the data suggest that tactile alerts may be especially advantageous in noisy task environments requiring long periods of vigilance.
Flight-Test of a Tactile Situational Awareness System in a Land-based Deck Landing Task BIBAFull-Text 142-146
  S. Jennings; G. Craig; B. Cheung; A. Rupert; K. Schultz
The National Research Council of Canada and Defence Research and Development Canada flight-tested the U.S. Naval Aerospace Medical Research Laboratory's Tactile Situational Awareness System (TSAS) in a dynamic task. The TSAS vest uses small pneumatic actuators or 'tactors' to transmit information to the pilot. Eleven pilots used the TSAS to cue horizontal axis performance in a land-based deck landing task flown in the NRC Bell 205 helicopter. Pilots tracked a vertically moving target with and without the TSAS in good and degraded visual conditions. The TSAS effectively cued longitudinal fore/aft drifts and reduced RMS error. It had less effect on lateral positioning error, possibly due to the presence of strong visual cues. Pilot situational awareness during degraded visual environment conditions in high sea states was significantly improved by the TSAS, as measured by the China Lake situational awareness rating scale. No change in workload, as measured by Modified Cooper Harper Workload Scale, was attributable to the TSAS use. The improvements in situational awareness and the reduction in longitudinal error suggest that the TSAS would be beneficial for helicopter ship deck landing.


Effects of Reliable and Unreliable Automation on Subjective Measures of Mental Workload, Situation Awareness, Trust and Confidence in a Dynamic Flight Task BIBAFull-Text 147-151
  Rebecca D. Brown; Scott M. Galster
Eight military pilots completed a study of human-interaction with reliable and unreliable automation in a complex air-to-ground search and destroy mission. Each mission consisted of four distinct stages. Automation was available in three of the four stages to aid the pilot in completing the required tasks. Automation reliability level was manipulated and combined factorially with two levels of workload, resulting in sixteen mission scenarios. Subjective measures of mental workload, situation awareness, trust, confidence, and judgments of the automation reliability were recorded after each mission. An analysis of the subjective measure ratings by mission workload level and the reliability of the first stage automation was performed. The results indicated that pilot trust in the automation was higher when the workload level was low and that there was a significant difference in confidence ratings between high and low workload levels, but only when the automation was unreliable. Design implications are discussed.
Unmanned Aerial Vehicle Flight Control: False Alarms Versus Misses BIBAFull-Text 152-156
  Stephen R. Dixon; Christopher D. Wickens; Dervon Chang
Thirty-two undergraduate pilots from the University of Illinois School of Aviation performed simulated military reconnaissance missions with an unmanned aerial vehicle (UAV). Pilots were required to: a) navigate the UAV through a series of mission legs, b) search for possible targets of opportunity, and c) monitor system health. They performed the missions under three types of auditory auto-alert aids (a 100% reliable system, a 67% reliable system with automation false alarms, and a 67% reliable system with automation misses), as well as a non-automated baseline condition. Results indicate that while reliable automation can benefit performance relative to baseline in the automated task, the unreliable automation aids reduced performance to that of baseline or worse. The automation false alarms and misses harmed performance in qualitatively different ways, with false alarm prone automation appearing to cause more damage than miss prone automation to both the automated task and the concurrent target search task.
Criterion Setting for Objective, Fourier Analysis Based Pilot Performance Metrics BIBAFull-Text 157-160
  Nicholas R. Johnson; Esa M. Rantanen; Donald A. Talleur
This study reports the development and evaluation of time series based objective pilot performance metrics. From a previously developed array of autocorrelation and Fourier analysis based metrics, five Fourier-based metrics that employed a threshold value were chosen to investigate their effectiveness in separating pilots who, based on instructor pilot (IP) evaluations, had either passed or failed a particular segment of an instrument proficiency check flight. An instrument landing system (ILS) approach was chosen for analysis based on IP feedback of what flight segments were most difficult to evaluate, had greatest sensitivity to overall pilot performance, and greatest criticality to the flying task. Further analysis showed that an optimal value for the criterion value could be found that most effectively separated those pilots that had passed the ILS segment from those who had failed. Criterion setting methods without external criteria using multidimensional scaling and cluster analysis techniques are also discussed.
An Empirical Investigation of the Effects of Controller Experience on Conflict Detection Ability Under Free Flight BIBAFull-Text 161-165
  Ashley Nunes
The progression towards the implementation of Free Flight has raised concerns over lapses in a controller's ability to detect the presence of conflicts amongst multiple aircraft pairs. These concerns have been supported through numerous empirical studies. An issue that has not received much attention is the impact of controller experience on conflict detection ability under Free flight. In the present study, fourteen controllers performed a conflict detection task. Variables manipulated included experience level and traffic load and controller performance was assessed using response time and accuracy as measures. Results from the study surprisingly suggest that controllers with more experience take longer to ascertain conflict likelihood under free flight conditions compared to their novice counterparts, even when the age factor is accounted for. We attribute the presence of the effect to the greater reliance on conventional cues, such as a route structure, and postulate that the absence of such cues produce the observed effects. The implications of these findings are discussed.
Atc Usability of the Navigation Reference System BIBAFull-Text 166-170
  Scott H. Mills; David A. Domino; Michael Borowski; Valerie Wendling; Celesta G. Ball; Dennis W. Rowe; John R. Helleberg
The navigation reference system (NRS) was designed to provide increased routing flexibility to aircraft operators and air traffic controllers. The NRS is a grid of points that employs a shorthand naming convention to specify waypoints independent of ground-based navigation aids. This study assessed usability of the NRS in simulated en route air traffic control (ATC). Scenarios were designed to exercise the NRS by varying factors such as traffic level and weather conditions. Twenty-four controllers representing four ATC facilities participated. Controllers completed six 45-minute simulation runs and completed questionnaires and debriefing sessions after each run. Controllers found the use of the NRS to be generally acceptable and usable even when traffic counts were high. The NRS was reported to provide significant added flexibility in performing important ATC rerouting procedures. Although several usability issues were identified, none were considered significant enough to outweigh the advantages of the NRS.
Measuring Traffic Awareness in an Integrated Hazard Display BIBAFull-Text 171-175
  Amy L. Alexander; Christopher D. Wickens
The ability for pilots to estimate traffic location, and how such estimations should be measured, was examined within an Integrated Hazard Display context. Twelve pilots viewed static images of traffic scenarios and then estimated the outside world locations of queried traffic represented in one of three display types (2D coplanar, 3D exocentric, and split-screen) and in one of four conditions (display present/blank crossed with outside world present/blank). Overall, the 2D coplanar display best supported both vertical (compared to 3D) and lateral (compared to split-screen) traffic position estimation performance. Furthermore, although pilots were faster in estimating traffic locations when the display was blank, accuracy was greatest when both the display and outside world were available.
Synthetic Vision Displays for In-Flight and Surface Navigation with Integrated Notam Information BIBAFull-Text 176-180
  F. D. Roefs; W. Theunissen; G. J. M. Koeners
A synthetic vision display provides the pilot with data regarding terrain, obstacles and traffic. At present, information from NOtices to AirMen (NOTAMs) is available from printouts obtained before the flight, but is not integrated into the synthetic vision display. A study consisting of two experiments was conducted to examine the effect and desirability of integrating electronic NOTAMs in synthetic vision displays. One experiment was concerned with in-flight navigation, the other with navigation on the airport surface. By combining quantitative and qualitative measures, it was established that by integrating NOTAMs in the displays pilots' situation awareness and performance improved, whereas mental workload decreased. Pilots rated the desirability of the integration of NOTAMs very highly.
Advanced Display Technology Effects on Flight Error and Workload in Average-Time Pilots BIBAFull-Text 181-185
  Steven M. Hall; Shawn M. Doherty; Albert Mion
A study of advanced cockpit displays (synthetic vision systems) and their impact on pilot performance and workload was investigated. Data from 42 average-time pilots were assessed for flight technical error and workload in simulated landings. Results indicated that the synthetic vision system greatly enhanced performance, but had little impact on workload.
Investigating Issues of Display Content Vs. Clutter during Air-to-Ground Targeting Missions BIBAFull-Text 186-190
  Maura C. Lohrenz; R. John Hansman
This paper investigates competing influences of display content and clutter on pilot performance during flight guidance and target acquisition phases of air-to-ground targeting missions. Based on interviews with F/A-18 pilots, a cognitive process model is presented to help understand how pilots use and transition between internal and external sources of information to support decision-making and aircraft control. Experiments were conducted in which subjects flew targeting missions using a flight simulator connected to the Navy's FalconView moving-map. In one experiment, subjects referred to three versions of the display: 1) a detailed map overlaid with critical mission symbology, 2) the map only, and 3) mission overlays only. Flight guidance and target acquisition performances were best with the overlays-only display. Performance was comparable or worse with the combination display and significantly worse with the map only, suggesting that the distraction of map clutter countered the benefits of map content.
Applying the Case/Control Methodology to the Study of Weather-Related General Aviation Accidents BIBAFull-Text 191-194
  Loren S. Groff; Jana M. Price
The case-control methodology is presented as an underused, yet versatile technique for studying risk factors in aviation accidents. By comparing information from accident flights and control flights conducted under similar circumstances, multiple hypotheses may be tested as they pertain to the accident outcome. This paper outlines practical methods for identifying and collecting aviation accident case-control data and presents examples in the context of an ongoing National Transportation Safety Board (NTSB) study of weather-related general aviation accidents. The paper includes a summary of study data collection from the point of initial accident notification, to identifying and gathering data from matching control pilots. Discussion of the specific difficulties and potential problems associated with the method is also included.
Identifying the Factors that Contributed to the Ueberlingen Midair Collision BIBAFull-Text 195-198
  Ashley Nunes; Tom Laursen
On the night of July 1, 2002, a Boeing 757 collided with a Tupolev-154 at 35,000 feet, resulting in 71 fatalities. Initially, this accident was immediately blamed on two individuals. First, the pilot of the Tupolev aircraft whose command of the English language was questioned when repeated descent instructions from ATC were not immediately responded to. The second individual was the controller on duty, who was accused of not exercising the abilities needed in order to detect the presence of a conflict between aircraft and resolve them. In this paper, we provide an analysis of the event, highlighting fundamental human and system errors that occurred that night: errors that contributed to the worst midair collision in recent history.
A Strategy for the Development of a Web-Based Tool to Reduce Aviation Maintenance Errors BIBAFull-Text 199-202
  Kunal Kapoor; Pallavi Dharwada; Nikhil Iyengar; Joel S. Greenstein; Anand K. Gramopadhye
The safety and reliability of air transportation depends on minimizing inspection and maintenance errors that occur in the aircraft maintenance system. Efforts have been invested to track maintenance errors. These efforts are reactive in nature: they analyze maintenance errors after their occurrence. There is a lack of standardization in the assessment of maintenance errors across the maintenance industry. Surveillance and auditing of maintenance activities are two important functions which help ensure airworthiness of an aircraft. A system that will document the processes and outcomes of these maintenance activities and will make this documentation more accessible will accomplish the goal of this research to reduce maintenance error. Such a system would then support robust and safer aircraft maintenance operations. Our research is developing a web-based surveillance and auditing tool (WebSAT) that promotes a standardized format for maintenance data collection, reduction and analysis to proactively identify the factors contributing to improper maintenance.
Improving Inspector's Performance and Reducing Errors General Aviation Inspection Training Systems (Gaits) BIBAFull-Text 203-207
  Raja J. Jacob; Satyen Raina; Saravanan Regunath; Ravikumar C. Subramanian; Anand. K. Gramopadhye
Inspection is an important step in ensuring product quality especially in aircraft industry where safety is the highest priority. Since safety is involved, effective strategies need to be set to improve quality and reliability of aircraft inspection/maintenance and for reducing errors. Humans play a critical role in visual inspection of airframe structures. Major advancements have been made in aircraft inspection, but General Aviation (GA) lags behind. Strategies that lead to improvement in inspection processes with GA environment will ensure reliability of the overall air transportation system. Training is one such strategy where advanced technology can be used for inspection training and reducing errors. A hierarchical task analytic (HTA) approach was used to systematically record and analyze the aircraft inspection/maintenance systems in geographically dispersed GA facilities. Using the task analytic approach a computer based training system (GAITS: General Aviation Inspection Training System) was developed for aircraft inspection that is anticipated to standardize and systematize the inspection process in GA. This paper documents the work involved in the development of General Aviation Inspection Training Systems.


Symbology Development for General Aviation Synthetic Vision Primary Flight Displays for the Approach and Missed-Approach Modes of Flight BIBAFull-Text 208-212
  Anthony P. Bartolone; Monica F. Hughes; Douglas T. Wong; Mohammad A. Takallu
Spatial disorientation induced by inadvertent flight into instrument meteorological conditions (IMC) continues to be a leading cause of fatal accidents in general aviation. The Synthetic Vision Systems -- General Aviation (SVS-GA) research element, an integral part of NASA's Aviation Safety and Security Program (AvSSP), is investigating a revolutionary display technology designed to mitigate low visibility events such as controlled flight into terrain (CFIT) and low-visibility loss of control (LVLOC). The integrated SVS Primary Flight Display (SVS-PFD) utilizes computer generated 3-dimensional imagery of the surrounding terrain augmented with flight path guidance symbology. This unique combination will provide GA pilots with an accurate representation of their environment and projection of their flight path, regardless of time of day or out-the-window (OTW) visibility. The initial Symbology Development for Head-Down Displays (SD-HDD) simulation experiment examined 16 display configurations on a centrally located high-resolution PFD installed in NASA's General Aviation Work Station (GAWS) flight simulator. The results of the experiment indicate that situation awareness (SA) can be enhanced without having a negative impact on task performance, by providing a general aviation pilot with an integrated SVS display to use when OTW visibility is obscured.
Factors Affecting Task Management in Aviation BIBAFull-Text 213-217
  Cristina Iani; Christopher D. Wickens
The present paper summarizes the results of a study investigating task management and task prioritization processes in aviation. Forty instrument rated pilots flew three curved approaches in a high fidelity simulation using a Synthetic Vision System (SVS) display. In addition to the primary task of flying, during the last approach they were required to select the approach path on the basis of environmental information concerning weather. The level of immersion in the task, the nature and saliency of the cues signaling the need to divert attention to the path selection task and the cost of not performing the secondary task were manipulated to investigate their influence on task prioritization. Our results indicate that cue saliency affected the frequency of the switch to the secondary task, while task compellingness did not show any reliable effect on task prioritization.
Traffic and Flight Guidance Depiction on a Synthetic Vision System Display: The Effects of Clutter on Performance and Visual Attention Allocation BIBAFull-Text 218-222
  Christopher D. Wickens; Amy L. Alexander; William J. Horrey; Ashley Nunes; Thomas J. Hardy
Fourteen pilots flew a synthetic vision system (SVS) display, through a terrain and traffic-rich environment in a high fidelity flight simulator. Traffic information was hosted on the SVS display. In a 2x2 factorial design, the SVS display hosted a highway-in-the-sky in half the conditions, and hosted an instrument panel overlay in the other half. We examined the effects of the resulting clutter from overlay (but reduced scanning) on routine flight performance, SVS traffic detection, and response to off-normal events, as these were mediated by visual scanning measures of attention allocation. The tunnel greatly improved flight path tracking and traffic detection, but slightly disrupted the detection of unexpected outside world traffic. The instrument panel overlay provided no benefits to tracking and a clutter-related time cost to SVS traffic detection. Visual attention was focused on the SVS display over half the time, and rarely on the outside world, even in visual meteorological conditions (VMC), a source of possible cognitive tunneling.
Eye-tracking and individual differences in off-normal event detection when flying with a Synthetic Vision System Display BIBAFull-Text 223-227
  Lisa C. Thomas; Christopher D. Wickens
Eye-tracking data were collected on eight pilots who flew a high fidelity flight simulator with a synthetic vision system (SVS) display, which included a tunnel-in-the-sky in half of the experimental conditions. In this paper, we examined the individual pilots' detection and response to two unexpected events, where the true information was inaccurately (or not) represented on the SVS display. The results indicate that the pilots who failed to detect these unexpected events spent most of their time scanning the SVS display, which included the tunnel, and rarely scanned the outside world. The pilot who detected the unexpected events showed scan patterns with a more even distribution of scans to the SVS, the outside world, and other displays even when the tunnel was present. This suggests that detection of unexpected in-the-world events depends on the individual pilot's vigilance in maintaining a regular scan pattern and resistance to "cognitively tunneling" into only one display.

AGING: Aging General Session

Expertise and Aging in a Pilot Decision-Making Task BIBAFull-Text 228-232
  Daniel Morrow; Lisa Soederberg Miller; Heather Ridolfo; Nina Kokayeff; Dervon Chang; Ute Fischer; Elizabeth Stine-Morrow
We examined age/expertise trade-offs in a laboratory pilot decision-making task. Expert and novice pilots read at their own pace brief scenarios that described simpler or more complex flight situations, then in a standard interview discussed the problem in the scenario and how they would respond if they were pilot-in-command. Decision making was measured by coding the protocols for correctly identifying the problems and solutions to problems. Scenario comprehension was measured by reading time and the accuracy of answering questions about the scenarios. All groups accurately identified the problems, but experts elaborated problem descriptions more than novices did. Older experts elaborated more, and older novices elaborated less, than their younger counterparts. Older experts also identified more appropriate solutions to problems while older novices identified less appropriate solutions compared to their younger counterparts. Reading time findings suggested that experts maintained decision-making accuracy by spending more time on critical information when reading more complex scenarios.
Age-Related Effects on Warning Symbol Comprehension BIBAFull-Text 233-237
  Mary F. Lesch
Prior research indicates that older individuals have greater difficulty in understanding warning symbols. However, research is inconclusive regarding age-related differences in understanding warning symbols and few studies have compared specific symbols. The current study examined 31 warning symbols for comprehension by younger (18-35) and older (50-65) individuals before and after training. Significant age-related differences were observed for 15 of the 31 symbols -- in every instance, the older group demonstrated poorer comprehension than the younger group. Training improved comprehension by both younger and older groups, but did not eliminate the effect of age. While rated familiarity was significantly correlated with comprehension performance, familiarity with the symbols did not explain the age effect. Rather, it is suggested that older adults's performance hinges to a greater extent on the effectiveness of symbols as cues to knowledge.
Investigating Issues in Aging and Work Performance Using a Customer Service Task Simulator BIBAFull-Text 238-242
  Joseph Sharit; Sara J. Czaja; Mario Hernandez; Yulong Yang
This paper discusses the use of a simulation tool for investigating information search performance in customer service work involving e-mail correspondence. Some unique opportunities for examining issues in aging and task performance that this customer service task simulator provides are also discussed. Integrated into this discussion are some results from an initial study of age group differences in performance of this type of task. Most importantly, this simulator's portability and the ease in which realistic customer queries can be captured enable it to be used as a platform for translating experimental research findings into more real-world settings by investigating task performance within the user's home environment.

AGING: Posters

Internet Searching by Ear: Decision Flow Diagrams for Sightless Internet Users BIBAFull-Text 243-247
  Megan E. Gorman; Laura G. Militello; Sarah J. Swierenga; Jesse L. Walker
A cognitive task analysis was conducted to better understand strategies that sighted and sightless users rely on to navigate the web and make sense of information encountered. Across participant groups, analyses revealed that users engaged in three primary cognitive modes: orienting themselves to the page, engaging in a goal-directed search, and completing the task by finding the results. Decision flow diagrams highlighted similarities and differences between user groups. While the sighted users consistently progressed in a linear fashion through the three modes, two distinct groups emerged within the sightless participants. Highly experienced sightless users exhibited actions much like those taken by the sighted users in their interaction with a weather website; however, interview data indicate that more complex cognitive processes were required during this portion of the task for the sightless user. Intermediate sightless users exhibited a more recursive flow that involved re-orienting themselves several times to complete the tasks.
Visual Characteristics of Elderly Drivers Aging Effects on Visual Acuity and Glare Feeling BIBAFull-Text 248-252
  Thurmon E. Lockhart; Bunji Atsumi; Arka Ghosh
The objective of the study was to investigate age related effects on visual acuity and reflected-glare associated with daytime and nighttime driving conditions. Fifty-six participants (28 young, 28 old) recruited from Virginia Tech student population and Blacksburg Community were tested in the study. Landolt's Circle Method was adopted to assess visual acuity under simulated daytime and nighttime conditions. Although, the age and distance main effects were found to be significant, no differences were reported among all the distances within the young group. The study also examined the effects of reflected headlamp glare on age and mirror types on the basis of angle of incidence, illumination-front-of-eyes and rating scores. The results indicated that with the same glare level (as measured by angle and illumination in front of the eye), elderly adults reported lower glare rating scores (i.e. worse feelings of glare). Furthermore, the young and elderly both reported lower De Boer's rating scores for planar driver-side mirrors than non-planar driver-side mirrors. This result can have practical implications in reducing nighttime discomfort glare for both young and elderly.
Effect of Aging on Driving Performance BIBAFull-Text 253-257
  Mustapha Mouloua; Edward Rinalducci; Janan Smither; J. Christopher Brill
The current research investigated the effects of aging on driving performance. Perceptual measures included far and near point acuity, stereopsis, a measure of lateral and vertical phoria, color vision; and spatial contrast sensitivity. Cognitive functioning was examined using the Useful-Field-of-View (UFOV) Test. In addition, each driver completed a Driving Habits Questionnaire (DHQ). Although older drivers tended to have fewer collisions and exhibited better adherence to speed limits in a simulated driving task than did younger, drivers, older drivers appear to be at a greater risk of having a collision, resulting from degraded divided and selective attention compared to the younger drivers.

AGING: Technology Aids for Aging

The Usability of Personal Digital Assistants as Prospective Memory Aids for Medication Adherence in Young and Older Adults BIBAFull-Text 258-261
  Vincent R. Lanzolla; Christopher B. Mayhorn
Medication adherence is essential to retaining functional independence into older adulthood. In the experiment reported here, 25 older and 26 young adults were asked to learn to use medication adherence software supported by a personal digital assistant (PDA). In addition to completing a battery of cognitive tests, each participant's PDA skill acquisition was assessed over time (i.e., during training, immediately following training, and after a delay). Consistent with previous research, older adults required longer to learn to use the PDA and committed more errors compared to younger adults. Over time, age differences in PDA performance were reduced suggesting that older adults might benefit from the use of PDAs as prospective memory aids.
An Analysis of Why People Lose Objects, How They Find Them, and Their Attitudes about a Technology Aid BIBAFull-Text 262-265
  Richard Pak; E. Peters Rodney; Wendy A. Rogers; Gregory D. Abowd; Arthur D. Fisk
The current paper presents findings from a survey examining, in a life span sample of healthy adults, the extent to which losing objects is perceived to be a problem. The goals of the survey were to determine who loses objects, what objects are lost, and what strategies are used to locate objects. The current findings suggest that young and middle-aged adults may consider losing objects to be a problem but older adults may not. Understanding what typical objects are lost, the strategies used to locate these objects, and attitudes toward technology may be applicable to the design of a technology aid for memory augmentation in the home.
Potential Intrusiveness of Aware Home Technology: Perceptions of Older Adults BIBAFull-Text 266-270
  Anne-Sophie Melenhorst; Arthur D. Fisk; Elizabeth D. Mynatt; Wendy A. Rogers
Older individuals in particular might benefit from an aware domestic environment. Yet, fear of intrusion is a potential barrier that might keep older adults from adopting smart technologies in the home. In this study, 44 participants (aged 65-75) were given a tour of the Georgia Tech Aware Home and shown five prototype smart home devices. The structured interviews after the tour yielded 2136 quotes containing the participants' opinions about living in a technology-rich home environment. A subset addressing technology intrusiveness of five devices is presented in this paper. The results show three domains of potential technology intrusion in the home as perceived by the older adults: physical obtrusiveness, invasion of privacy, and security risk. Technology intrusiveness represented 19% of the total technology judgments, but accounted for almost half of the negative judgments in general. The distribution of the participants' conditional statements (e.g., I wouldn't mind privacy intrusion if) suggested a careful weighing of potential intrusiveness against benefits such as prolonged independence for some of the devices in particular.
Designing Websites for Older Adults: The Relationship between Guideline Compliance and Usability BIBAFull-Text 271-274
  Traci A. Hart; Barbara S. Chaparro; Charles G. Halcomb
Three senior websites with varying levels of compliance to "senior-friendly" guidelines were evaluated for efficiency and usability with older adults. Results indicate that the website compliant with the most senior-friendly" guidelines resulted in higher task success, but did not result in significantly lower time on task or fewer number of pages visited. In addition, the site compliant with the most "senior-friendly" guidelines did not result in higher satisfaction or preference. The importance of adding usability testing to the website design process, especially for this target audience, is highlighted.
Effects of Computer Presentation Format on Learning in the Elderly BIBAFull-Text 275-279
  Celeste Y. M. Shai; Albert W. L. Chau
Younger and older adults studied two descriptions of the processes of measuring blood pressure and bees making honey under one of three experimental conditions: (a) text-only; (b) text plus narration; and (c) graphics plus narration. A control group without studying the materials was included in each age group. On verbal recall tests, the control group in both age groups performed more poorly than all the respective experimental groups, which were not different from each other. On transfer tests, the younger participants in the control group performed more poorly than all the experimental groups, which were not different from one another. For older participants, control group performed more poorly than text plus narration and graphics plus narration groups. Moreover, the text plus narration group performed better than the text-only group. These results revealed potential differences between the facilitations provided by verbal and non-verbal visual information for younger and older adults in learning novel information.

COGNITIVE ENGINEERING AND DECISION MAKING: Task Planning, Interruptions, and Situation Awareness

Human in the Loop Evaluation of a Mixed-Initiative System for Planning and Control of Multiple Uav Teams BIBAFull-Text 280-284
  Emilie M. Roth; Mark L. Hanson; Chris Hopkins; Vince Mancuso; Greg L. Zacharias
This paper describes a 'Human in the Loop' evaluation of an early prototype mixed-initiative control system that generated plans for single operator supervision of multiple unmanned aerial vehicles (UAV) missions. The objectives of the evaluation were to assess to what extent human operators were able to understand the plans generated by the automated controllers as well as to point to additional support requirements to drive further development of mixed-initiative planning systems. Six former fighter pilots served as test participants. Multiple convergent measures were utilized to evaluate the ability of users to understand and evaluate the plans generated by the automated controller. While test participants were able to understand the plans, the results provided compelling evidence for the need to communicate more effectively the rationale behind plan elements proposed by the automated controller and to provide 'levers'to enable the user to modify the plan. These results point to important challenges for design of 'mixed-initiative'controllers to enable the human and automated controller to function as effective 'partners'.
Describing Situation Awareness at an Emergency Medical Dispatch Centre BIBAFull-Text 285-289
  B. L. William Wong; Ann Blandford
In this paper we describe findings on Situation Awareness (SA) from a field study on decision making in ambulance control, or Emergency Medical Dispatch (EMD). Triangulating the results from observations and Contextual Inquiry interviews of 18 participants, with 13 Critical Decision Methods in-depth interviews, we found, among other things, that EMD work can be classified as routine operations, start of a major incident, and when an incident is established. Higher levels of SA were exhibited by dispatchers for non-routine or major incidents, than for routine events. Senior dispatchers, or allocators, developed a "picture in the head" of the situation, and used that to plan ahead and to evaluate their plans. They were also found to use an information hub strategy to develop and maintain their SA. Using a combined Wickens (2000) and Endsley (1995) framework, we see allocators interleaving their attention and information handling between routine and major incidents.
Interruption and Reorientation Effects of a Situation Awareness Probe on Driving Hazard Anticipation BIBAFull-Text 290-294
  Alastair McGowan; Simon Banbury
A driving-based Hazard Perception Test of anticipation (HPT) was applied alongside an interruption-based Situation Awareness (SA) probe to investigate the effects of interruption and reorienting the operator to the task. Content of the SA probe was manipulated in four conditions: No queries, SA queries, orienting queries, and irrelevant queries. The findings were firstly that the HPT scores correlated with the SA probe scores in the SA queries condition. Secondly, there was a negative effect of interruption on HPT scores. Finally, HPT scores increased during SA queries and orienting queries but not during irrelevant queries. The results imply that previous research showing no interruption effects from SA probe methods may be due to the orienting effects of the queries compensating for a decrease in scores caused by interruption.
The Effect of Frequent Versus Infrequent Interruptions on Primary Task Resumption BIBAFull-Text 295-299
  Christopher A. Monk
Recent interruptions research suggests that the timing of interruptions can play a critical role in the level of task primary disruption. An unanswered question regarding interruption timing is whether greater task disruption in terms of primary task resumption time is experienced with more frequent interruptions. The present study used a VCR programming task with a pursuit-tracking interruption task to measure how quickly people resume the primary task after an interruption. The results showed that primary task resumption times were faster for more frequent interruptions, which was contrary to the predicted outcome. In addition, frequent interruptions did not result in the more resumption errors or longer time-on-task results as predicted. These results are discussed as evidence that more frequent interruptions may compel people to adopt aggressive goal maintenance strategies when dealing with interruptions, but further research is required to fully test this hypothesis.
Paintshop: A Microworld Experiment Investigating Temporal Decisions in a Supervisory Control Task BIBAFull-Text 300-304
  Michael Hildebrandt; Michael Harrison
This paper explores temporal aspects of control behavior in order to support the design of systems where functions can be allocated flexibly in time. Dynamic Function Scheduling, an extension of Dynamic Function Allocation approaches, highlights the role of temporal information and temporal reasoning in supervisory control decisions. The microworld experiment presented 30 participants with a supervisory control task where they had to monitor production in a simulated paint station, make strategic decisions about automatic or manual production, and handle faults. Independent variables were event rate, the knowledge of event rate information, the availability of an online progress indicator, and the cost of fault servicing. Results showed that knowledge of event rate information improved performance, but availability of an online progress indicator had no additional effect. Implications for the investigation of temporal control behavior are discussed.

COGNITIVE ENGINEERING AND DECISION MAKING: Applying Cognitive Engineering to Meteorological Forecasting

Applying Cognitive Engineering to Meteorological Forecasting: From Analysis of Expertise to Human-Centered Design BIBAFull-Text 305
  Emilie M. Roth
Meteorological forecasting is an important area of study from both a theoretical and applied perspective. It provides a paradigmatic example of a complex decision-making task that requires integration of (and projection from) multiple, diverse sources that can be incomplete, ambiguous and uncertain. Further, it is a collaborative task that involves understanding and adapting to the goals and information needs of the forecast consumer (e.g., a military pilot, a fisherman, a commuter). This symposium showcases diverse cognitive engineering approaches that have been successfully applied to the analysis of weather forecasting and design of human-centered support systems. Topics include skills, strategies and mental models that underlie weather forecasting expertise; alternative cognitive analysis methods for uncovering the basis of expertise; human-centered approaches that 'bridge-the-gap'between analysis of expertise and design of support systems; and the use of controlled studies to explore the benefits of human-centered systems for weather forecasting. A practicing Navy meteorologist from the Ocean and Atmospheric Science and Technology Directorate at the Naval Research Laboratory will serve as discussant.
The Role of Comparison in Weather Forecasting: Evidence from Two Hemispheres BIBAFull-Text 306-310
  Susan S. Kirschenbaum
Northern hemisphere weather forecasters from the United States Navy (USN) and their Southern hemisphere counterparts in the Royal Australian Navy (RAN) were observed while making forecasts for air operations. A Comparative Cognitive Task Analysis showed that both groups employed the cognitive task of Comparing information to select among, validate, or modify the output of numerical models when making forecasts. This process was interpreted as key to the forecaster adding value to the automatic output of weather models.
Dynamic Mental Models in Weather Forecasting BIBAFull-Text 311-314
  J. Gregory Trafton
There are many definitions, descriptions, and usages of the term "mental model." Frequently, the definition of mental model is not described, leaving what the author means as an exercise for the reader. I propose a very explicit definition for a dynamic mental model and then show how that definition can be applied in the domain of meteorological forecasting. Specifically, I suggest that a dynamic mental model is a mix of images and propositions, relies on qualitative and spatial relationships, allows dynamic, runnable results to be inspected, and results in an inference. Finally, I offer suggestions on how to improve the usefulness of the term mental model.
Weather Forecasting and the Principles of Complex Cognitive Systems BIBAFull-Text 315-319
  Robert R. Hoffman; John W. Coffey
This presentation will illustrate some of the principles for the design of complex cognitive systems that were manifested in a recent project on weather forecasting (Hoffman, et al., 2000). One focus here is on how technologies and workspaces can facilitate or interfere with knowledge-sharing. A second focus is the notion of methodological opportunism. This is illustrated by a discussion of a new knowledge elicitation method, the Cognitive Modeling Procedure, which is intended to support the rapid refinement and behavioral validation (in the field setting) of macrocognitive models of practitioner reasoning.
Improved Workflow, Environmental Effects Analysis and user Control for Tactical Weather Forecasting BIBAFull-Text 320-324
  James Ballas; David Jones; Keith Kerr; Beth Kirby; Robert Carr; Ted Tsui; John Cook; Ramesh Mantri; Susan Kirschenbaum; Megan Gibson
A project called Environmental Visualization (EVIS) conducted and completed testing of a capability to improve the air strike forecasting workflow. The capability was tested in a yoked experimental paradigm that had pairs of fleet forecasters generating an air strike forecast, one forecaster using the EMES capability and one using the current web-based tools. Three pairs of forecasters were tested, and within each pair, the EMES capability supported substantially faster (~40%) forecast completion time. Feedback from the fleet users and personnel was positive about the approach we are taking and the capability that was tested. The team received substantial constructive feedback on the initial capability and will incorporate this into the next development phase.


A Centralized Display for Mission Monitoring BIBAFull-Text 325-329
  Anna C. Trujillo
Humans traditionally experience a vigilance decrement over extended periods of time on reliable systems. One possible solution to aiding operators in monitoring is to use polar-star displays that will show deviations from normal in a more salient manner. The primary objectives of this experiment were to determine if polar-star displays aid in monitoring and preliminary diagnosis of the aircraft state. This experiment indicated that the polar-star display does indeed aid operators in detecting and diagnosing system events. Subjects were able to notice system events earlier and they subjectively reported the polar-star display helped them in monitoring, noticing an event, and diagnosing an event. Therefore, these results indicate that the polar-star display used for monitoring and preliminary diagnosis improves performance in these areas for system related events.
Error Management on Modern Flight Decks: How Pilots Explain and Recover from Unintended Actions and Outcomes BIBAFull-Text 330-334
  Mark I. Nikolic; Nadine B. Sarter
Errors are a fundamental aspect of human adaptation in complex systems. Efforts to reduce and/or eliminate errors through training and design have met with only limited success. Therefore, it is critical to invest also in effective support for error management (the detection, explanation, and recovery from errors) to mitigate their negative consequences. To date, most research on error management has focused on the first step in this process -- error detection. Instead, this paper presents a subset of results from a recent simulator study that examined the role of error explanation and the nature and effectiveness of error recovery strategies. Process tracing was used to analyze error management activities of pilots on highly automated flight decks. Our findings suggest that incomplete mental models of automation function limit error explanation and often lead to recovery strategies that rely on either "resetting" the system or serendipitous error evasion prior to negative consequences, or reverting to lower levels of automation when immediate corrective actions become necessary. These findings will be discussed in terms of their implications for training and design.
Surprise and Unexpectedness in Flying: Database Reviews and Analyses BIBAFull-Text 335-339
  Janeen A. Kochan; Eyal G. Breiter; Florian Jentsch
This database search and evaluation was performed to ascertain what types of situations pilots consider surprising or unexpected. The purpose of the investigation was to determine if natural categories of events emerge from the existing accident, incident, and event reporting data commensurate with the current operational and research focus concerned with unexpected events and aviation safety. The underlying question was whether the involvement of surprise or unexpectedness in events may be a precursor to a loss of attention, increased workload, or other interruptions of ongoing processes, which may then contribute to an unwanted outcome of a maneuver, or an entire flight as revealed in these database reports. The study was also conducted to facilitate the development of a conceptual framework for the study of unexpected events in aviation.
General Aviation Pilot Takeoff into Adverse Weather: The GoNo-Go Equation BIBAFull-Text 340-344
  William Knecht; Howard Harris; Scott Shappell
This exploratory study assessed pilot takeoff behavior into adverse weather. Sixty general aviation pilots were presented with three levels of simulated ground visibility (1, 3, 5 sm), two levels of cloud ceiling (1000', 2000', and two levels of real financial incentive (straight salary, salary + bonus for takeoff). Trends were found in regression analysis for a number of environmental predictors of takeoff, though not for personality or demographic predictors. Methodological and analytical concerns inherent to this type of study were encountered and identified.
Verbal Protocol Analysis of Pilots' Cardinal Direction Judgments BIBAFull-Text 345-349
  Johnell O. Brooks; Leo Gugerty
This study investigated the types of strategies experienced navigators use to make cardinal direction judgments. While these judgments are important and necessary in navigation, people are generally poor at this task. Verbal protocol analysis revealed the strategies used by pilots in making cardinal direction judgments. These strategies were then compared to those previously identified using less experienced, non-pilot navigators (Gugerty & Brooks, 2001). Prior research on navigation tasks has pointed to mental rotation as the most common primary strategy. Our protocol analysis revealed a strategy not previously identified for other navigational tasks, heading referencing, suggesting that people often use a strategy involving little mental rotation for cardinal direction judgments. Individual participants used one of three patterns of primary strategies: mental rotation only, heading referencing only, or a combination of mental rotation and heading referencing. The novices relied equally on mental rotation and heading referencing while the pilots' primary strategy was heading referencing.

COGNITIVE ENGINEERING AND DECISION MAKING: Brunswik's Lens Model in HF Research: Modern Applications of a Classic Theory

Brunswik'S Lens Model in Human Factors Research: Modern Applications of a Classic Theory BIBAFull-Text 350-354
  Kathleen L. Mosier; Alex Kirlik
As we develop new ways of looking at decision making in applied contexts, such as those outlined in naturalistic decision models, it is easy to assume that these new models should be used in place of 'old'theories in investigations of human decision making -- and in many cases it may be appropriate to do so. In substituting the new for the old, however, it is important not to lose sight of the potential contributions that theoretically sound and empirically tested models can make to our understanding of judgment and decision making in modern environments. The purpose of this panel is to highlight a classic theoretical and methodological approach to the judgment process, Egon Brunswik's probabilistic functionalism and associated Lens Model framework (e.g., 1943; 1956; Hammond & Stewart, 2001), to present its basic tenets, and to discuss its viability and applicability in the context of modern human factors investigations (Kirlik, 2001). In particular, defining facets of Brunswikian theory and the Lens Model make this approach ideal for explorations of human judgment in high-technology environments.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Factors in Intelligence Analysis

Cognitive Factors in Homeland Defense: The role of human factors in the Novel Intelligence from Massive Data (NIMD) Program BIBAFull-Text 355-356
  David A. Thurman; Wayne D. Gray
The Advanced Research and Development Activity (ARDA) funds innovative, creative, and high-risk research to advance the state-of-the-art in information technologies. One program aims to develop methods for supporting intelligence analysts in discovering "novel intelligence from massive data" (NIMD). An important feature of this program is the role it gave to cognitive factors. The call-for-proposals said, "Thus, NIMD is about human interaction with information in a way that permits intelligence analysts to spot the telltale signs of strategic surprise in massive data sources -- building tools that capitalize on human strengths and compensate for human weaknesses to enhance and extend analytic capabilities." This symposium brings together representatives of five of the NIMD teams. While the approaches and projects are diverse, all are focused at improving analysts' ability to extract hidden patterns from massive sources of data.
Cognitive Tasks In Information Analysis: Use of Event Dwell Time to Characterize Component Activities BIBAFull-Text 357-361
  Thomas F. Sanquist; Frank L. Greitzer; Antoinette Slavich; Rik Littlefield; Janis Littlefield; Paula Cowley
Technology-based enhancement of information analysis requires a detailed understanding of the cognitive tasks involved in the process. The information search and report production tasks of the information analysis process were investigated through evaluation of time-stamped workstation data gathered with custom software. Model tasks simulated the search and production activities, and a sample of actual analyst data were also evaluated. Task event durations were calculated on the basis of millisecond-level time stamps, and distributions were plotted for analysis. The data indicate that task event time shows a cyclic pattern of variation, with shorter event durations (< 2 sec) reflecting information search and filtering, and longer event durations (> 10 sec) reflecting information evaluation. Application of cognitive principles to the interpretation of task event time data provides a basis for developing "cognitive signatures" of complex activities, and can facilitate the development of technology aids for information intensive tasks.
Simborgs and Simulated Task Environments for Engineering Next Generation Workstations for Intelligence Analysts BIBAFull-Text 362-366
  Wayne D. Gray; Michael J. Schoelles; V. Daniel Veksler
Intelligence analysts require innovative software environments for searching massive databases, hypothesis generation and test, record keeping, crosschecking and so on. Yet, as important as such tools are, their development cannot be allowed to ignore the hard won lessons from cognitive science and human-computer interaction -- that human cognition is embodied cognition and that interface design has a large role to play in increasing productivity and reducing human error. We propose an approach to the cognitive engineering of integrated task environments by the use of simulated cyborgs (simBorgs) that combine computational embodied-cognitive models of interactive behavior with artificial intelligence based reasoning components in a simulated task environment. Our goal is the creation of intelligent agents, simBorgs, that will work tirelessly to perform usability testing on various combinations of tasks and interfaces.
Cognitive Factors in Homeland Defense Reusing Intelligence Analysts' Search Plans BIBAFull-Text 367-370
  Elizabeth Whitaker; Robert Simpson; Laura Burkhart; Reid MacTavish; Collin Lobb
Because of the huge volumes of data that open source intelligence analysts must search, effective information gathering on the web, is a complex activity requiring planning, text processing, and interpretation of extracted data to find information relevant to a major intelligence task or subtask (Knoblock, 1995), (Lesser, 1998) and (Nodine, Fowler et al., 2000). This paper describes our use of analysts' plans to build a case library of reusable automated plans. This process involves analyzing analysts' approaches to identify the important characteristics of a knowledge discovery plan for case indexing and retrieval and devising techniques for representing plans so that they can be automatically adapted and executed. For this research, we are not building a "complete" case library, but are developing approaches and guidance for getting maximum usage out of the cases that are represented and providing processes for identifying further areas for case development. The knowledge discovery plan categories that we have identified thus far correspond to different contextual domains that may be indicators of terrorist activities. When a plan is selected from one of these categories, it is adapted, and the resulting plan is executed, relevant information is extracted from unstructured documents, and the extracted information is used to make further inferences and launch additional searches.
Capturing user Intent for Information Retrieval BIBAFull-Text 371-375
  Hien Nguyen; Eugene Santos; Qunhua Zhao; Hua Wang
Gathering information and making decisions based on retrieved information are the important tasks that every intelligence analyst is doing. User modeling techniques have been exploited to help analysts to search for information effectively. To justify the effects of any user modeling technique on helping analysts retrieve quality documents relevant to their tasks, we need to have a comprehensive evaluation method, which assesses the improvement of retrieval performance and user performance. In this paper, we describe our evaluation of a cognitive user model for information retrieval with regards to retrieval performance. Our user model captures user intent dynamically by analyzing behavioral information from retrieved relevant documents for improving the retrieval performance and user's performance. In this evaluation, we assess the user model's short-term effects on a single query, and the user model's long-term effects on the whole search session. We compare our approach with the best traditional approach for relevance feedback in information retrieval, the Ide dechi, which is the approach of modifying queries using term frequency from relevant/non-relevant documents. We use the oldest collection of information retrieval on aerodynamics called CRANFIELD. The results of this evaluation show that by exploring user intent, we achieve competitive performance in the feedback run compared to Ide dec-hi. At the same time, our user model approach offers the advantages of retrieving more quality documents at the initial run compared to the term frequency inverted document frequency (TFIDF) approach. Our results have shown that our user modeling approach can be used to improve efficiency, learnability and interactivity of an information retrieval system.
Supporting Mutual Understanding in a Visual Dialogue between Analyst and Computer BIBAFull-Text 376-380
  Alan R. Chappell; Andrew J. Cowell; David A. Thurman; Judi R. Thomson
The Knowledge Associates for Novel Intelligence (KANI) project is developing a system of automated "associates" to actively support and participate in the information analysis task. The primary goal of KANI is to use automatically extracted information in a reasoning system that draws on the strengths of both a human analyst and automated reasoning. The interface between the two agents is a key element in achieving this goal. The KANI interface seeks to support a visual dialogue with mixed-initiative manipulation of information and reasoning components. The interface must achieve mutual understanding between the analyst and KANI of the other's actions. Toward this mutual understanding, KANI allows the analyst to work at multiple levels of abstraction over the reasoning process, links the information presented across these levels to make use of interaction context, and provides querying facilities to allow exploration and explanation.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognitive Modeling and Interface Design

Modeling Human Transcription Typing with Queuing Network-Model Human Processor (QN-MHP) BIBAFull-Text 381-385
  Changxu Wu; Yili Liu
Typing is one of the basic and prevalent activities in human machine interaction. John (1988, 1996) proposed a PERT (Project-Evaluation-Research-Technique)-based model called TYPIST, which modeled 21 of the 31 behavioral phenomena in transcription typing (Salthouse, 1986, 1987; Gentner, 1983). However, TYPIST can only analyze the typing phenomena along the time dimension; it can not model error and eye movement of typing. Based on the queuing network theory of human performance (Liu, 1996, 1997) and current discoveries in brain and cognitive sciences, this paper proposes a queuing network model of typing which successfully modeled not only all the 21 phenomena modeled by TYPIST, but also 13 additional phenomena in transcription typing including 5 typing error phenomena, 3 eye movement phenomena and 2 brain imaging phenomena. Further developments of the queuing network model in modeling typing and other tasks, and its value in proactive ergonomic design of typing interfaces are discussed.
Multimodal Interaction: Multi-Capacity Processing Beyond 7±2 BIBAFull-Text 386-390
  Shatha N. Samman; Kay M. Stanney; Joseph Dalton; Ali M. Ahmad; Clint Bowers; Valerie Sims
Multiple resource theory suggests that enhancements in human information management capacity may be realized via multimodal interaction. The possibility of leveraging multiple sensory systems to maximize working memory (WM) throughput becomes essential as the information age conveys volumes of data that would overburden the visual channel alone. The current study proposes an expansion of the current bi-modal (verbal, visual/spatial) model of WM to a multimodal WM system, which includes verbal, visual, spatial, kinesthetic, tactile, and tonal component subsystems. Single modality capacity was measured for each proposed subsystem. In addition, multimodal capacity was calculated for combined modalities. Results demonstrated that multimodal WM capacity surpasses that of single modality capacity. Most notably, multimodal WM capacity averaged nearly three times the 'magic number'seven.
Developing a Formal Model of Human Memory in a Simulated Air Traffic Control Conflict Detection Task. BIBAFull-Text 391-395
  Peter J. Kwantes; Andrew Neal; Shayne Loft
This paper describes the development of a formal model of conflict detection in a simulated air traffic control task. The model assumes that people rely on information from two sources when performing conflict detection tasks: perceptual cues, and memory for prior examples. The architecture of the memory system is based on Hintzman's (1986) Minerva 2 model, which is a multiple trace model of episodic and semantic memory. The model was able simulate the performance of naïve experimental participants on a conflict detection task. Aspects of human data that were simulated included differential effects of item repetition on reaction times and false alarm rates during training, and positive and negative transfer from prior examples at test.
Rafiv: A Method for Cognitive Usability Analysis BIBAFull-Text 396-400
  Melanie Diez; Lance Sherry; Deborah A. Boehm-Davis
RAFIV is a cognitive usability method that is based on the label-following heuristic found in the exploratory learning literature. This paper describes the empirical evidence and theoretical foundation for the RAFIV method, a five-stage model that describes a user's cognitive steps as they perform a task. The contributions of this method to the usability literature are discussed, as well as a comparison between RAFIV and other methods such as GOMS and the Cognitive Walkthrough.
An Exploratory Qualitative Study of Computer Network Attacker Cognition BIBAFull-Text 401-405
  Terry Stanard; W. Robert Lewis; Donald A. Cox; David A. Malek; John Klein; Randy Matz
Many computer network defenders do not know how malicious hackers think and act during a network (McCloskey & Chrenka, 2001). To study attacker cognition, experienced hackers were recruited to attack a Windows 2000 network and pursue three goals: Deface the website, steal (faux) credit card numbers, and read email. Participants wrote a report of what they did, and a post-attack cognitive task analysis interview was conducted. Logs were also captured on the network including firewall, snort IDS, and Microsoft applications (IIS, SQL, Exchange). An Attacker Cognition Model based on data collected from five participants was created. The model has two basic properties: It describes the cognitive steps followed by an attacker, and describes several passes through these steps that the attacker follows as s/he penetrates several layers deep into a network. Future research using smaller sample sizes and multiple studies using the same participants is encouraged.

COGNITIVE ENGINEERING AND DECISION MAKING: Designing Support for Intelligence Analysis

Designing Support for Intelligence Analysts BIBAFull-Text 406-410
  William C. Elm; Malcolm J. Cook; Frank L. Greitzer; Robert R. Hoffman; Brian Moon; Susan G. Hutchins
Intelligence analysis is a prototypical example of a situation that can be described by the phrase "coping with complexity," given a variety of complicating factors including (but certainly not limited to) massive amounts of data, inherent uncertainty in the data, dynamism in the underlying world, and the risks associated with the conclusions drawn from the data. Given this complex nature of intelligence analysis, a wide variety of advanced visualization tools are continually being developed in hopes of designing support for the analysis process. In addition, a number of different cognitive analysis activities are ongoing in hopes of deriving requirements for future support tools. The goal of this panel is to present a sample from both areas in hopes of providing an integration of efforts and thus more effective support tools for intelligence analysts. We have four speakers presenting an analytic perspective, one from a tool development perspective, and one from a support function (the medium between analysis and design) perspective. This should provide an interesting set of complementary discussions into this topic area.


Applying the Proximity Compatibility and the Control-Display Compatibility Principles Toward Engineering Design using Configural Interfaces BIBAFull-Text 411-415
  Ling Rothrock; Kimberly Barron; Timothy W. Simpson; Mary Frecker; Chris Ligetti; Russell R. Barton
This paper presents a study to investigate the applicability of two display design principles toward the development of interfaces for engineering design. The first principle, called the Proximity Compatibility Principle, specifies that displays relevant to a common task or mental operation should be rendered close together in perceptual space. The second principle, called the Control-Display Compatibility Principle, stipulates that the spatial arrangement and manipulation of controls should be easily distinguishable. We conducted an experiment comparing the ability of subjects to search for effective designs using a separable versus two configural interfaces in a multiple-objective engineering design task. Results suggest that the Proximity Compatibility Principle is an effective indicator of task performance. Moreover, we found that the Control-Display Compatibility Principle can be used as an indicator of performance efficiency.
Heuristic Automation for Decluttering Tactical Displays BIBAFull-Text 416-420
  Mark St. John; Daniel I. Manes; Harvey S. Smallman; Bela A. Feher; Jeffrey G. Morrison
Tactical displays can quickly become cluttered with large numbers of symbols that can compromise effective monitoring. Here, we studied how heuristic automation can aid users by intelligently "decluttering" the display. In a naval air defense task, users monitored a cluttered airspace and executed defensive responses against significant threats. An algorithm continuously evaluated aircraft for their levels of threat and decluttered the less threatening ones by dimming their symbols. As expected, 27 Navy experts appropriately distrusted and spot-checked the automation's assessments, and decluttering did not affect which aircraft were judged significantly threatening. Nonetheless, decluttering improved response timeliness to threatening aircraft 25% compared with a baseline display with no decluttering, it increased attention to threats, and 25 of 27 participants preferred decluttering. Heuristic automation, when properly designed to guide users' attention by decluttering less important objects, should prove valuable in many cluttered monitoring situations.
Multimodal, Multitask Interaction Design: A Follow up Study to Challenge Unimodal Design Assumptions BIBAFull-Text 421-425
  David Jones; Ali Ahmad; Kay M. Stanney; Clint A. Bowers
Advances in technology are enabling multiple sensory channels to be utilized in presenting information. Nevertheless, the human operator can become easily overwhelmed if an overabundance of information is presented in a non-systematic manner. Current design guidelines are primarily tailored towards unimodal or at most bimodal systems. Thus, the question becomes how to coordinate multiple sources of information in multimodal multitasking environments, and what design guidelines are needed to direct development of such interactive systems. The current study builds on a previous study and seeks to extend unimodal design theories to multimodal principles; it identifies some interesting differences in unimodal vs. multimodal multitask interaction.
Supporting Synchronous Distributed Communication and Coordination through Multimodal Information Exchange BIBAFull-Text 426-430
  Chih-Yuan Ho; Nadine B. Sarter
Increasingly, operators in complex event-driven domains, such as the military, need to coordinate their goals and activities with numerous co-located and distributed human and machine agents. One promising way to support this requirement is the introduction of multimodal interfaces that afford functions such as increased bandwidth, complementarity, redundancy, and substitution. To inform the design of a robust multimodal system, the present study explored natural tendencies for, and the role of context in, modality usage in the context of simulated battlefield operations. Three groups of three ROTC cadets/officers each completed a set of 30-minute scenarios. The within-subject variables included participant location, the availability of radio communication, the amount of coordination required by the scenario, and the tempo of operations. Our findings show that participants were highly selective in their use of multiple modalities. Multimodal interaction was observed primarily in the context of spatial tasks and for the purpose of supporting grounding, complementarity, and disambiguation. Joint modality usage patterns evolved over time within groups and varied as a function of factors such as scenario and interface management demands. The findings from this study provide important guidance for the design of multimodal combined HCI and CSCW interfaces and show that multimodal information exchange is a highly effective means of coordination.
The Impact of Asynchronous Multimedia Communications on Understanding and Recall BIBAFull-Text 431-435
  Jennifer I. Bower
This research focused on the design of software environments to support rich asynchronous communication and to understand the impact of such communications on understanding and recall in a military context. The goal was to explore how the design of a multimedia asynchronous communication tool influenced the understanding and recall of information. 46 ROTC cadets each received a company Operations Order, and based on that were required to write a platoon OPORD followed by two recall questions. Half of the cadets received the company OPORD in a conventional text format that included a static map overlay. The other half received the OPORD with 4 subsections presented with a multimedia presentation tool that included synchronized animation and voice narration. Overall, our findings show that the group that viewed the multimedia presentation recalled mission critical information 26-47% more often.


On the Study of Performance and Trust in Aided, Adversarial Decision Making BIBAFull-Text 436-438
  Santosh Basapur; Ann M. Bisantz
Aided-adversarial decision-making (AADM) refers to military command and control decisions in environments in which computerized aids are available to groups of colocated and distributed decision-makers, and in which there is a potential for adversarial forces to tamper with and disrupt such aids. It is therefore necessary to understand the extent to which decision-makers rely on or use these decision aid systems, and factors affecting that reliance. Researchers have suggested that trust can affect how much people accept and rely on increasingly automated systems. Ongoing research and experimentation in the Center for Multi-source Information Fusion at the University at Buffalo has been addressing these concerns.
Effect of Error Severity on Human Trust in Hybrid Systems BIBAFull-Text 439-443
  Mohammad T. Khasawneh; Shannon R. Bowling; Xiaochun Jiang; Anand K. Gramopadhye; Brian J. Melloy
Computerized systems are often employed to support control and decision-making tasks in complex and dynamic environments. Trust or mistrust in these systems has been demonstrated to significantly affect operator performance. Consequently, errors of trust or mistrust may compromise system performance, with potentially disastrous results. Accordingly, trust should be considered in both the design and operation of human/machine systems. In order to do so, metrics and methods for the measurement of trust must be developed along with models of human performance that incorporate trust and related system variables. Current approaches to trust measurement rely solely on subjective metrics, which are based on different theoretical concepts of trust between humans that may not necessarily be as relevant to machines. Although researchers have been able to establish a relationship between trust and behavior, these models lack an analytic foundation. Therefore, the purpose of this research is to develop a quantitative approach that relates trust to changes in system parameters and severity of errors.
Error-Associated Behaviors and Error Rates for Robotic Geology BIBAFull-Text 444-447
  Jacob Wagner; Geb Thomas; Justin Glasgow; Robert C. Anderson; Nathalie Cabrol; Edmond Grin
Humans are often blamed for errors in complex systems. A number of taxonomies exist for classifying human errors, but recent doubts have been raised as to whether these are actually errors or simply processes involved in both correct and incorrect decisions. A field test was designed to address some of these issues. During the field test, three geologists made assessments about the recent and past environment based on robotically collected data. The decisions were classified based on previous error taxonomy. Each conclusion was then checked for accuracy. From this data, the error rate for specific behaviors could be calculated. The results indicate many of the behaviors describe earlier as erroneous actually produce correct decisions most of the time. One behavior is singled out as producing a majority of the errors and further research is needed to better understand its causes.
Exploring the Relationship between Decision Appropriateness and Mission Effectiveness in A Simulated Command Control Task BIBAFull-Text 448-452
  Scott M. Galster; Robert S. Bolia
The development of automated decision support systems requires a real-time metric of decision quality. Historical links between decision quality and mission effectiveness suggest that the former is predictive of the latter, and thus the outcome is what needs to be measured. The purpose of the present paper is to describe an experiment designed to separate the measurement of decision quality from that of mission effectiveness. Mission effectiveness and decision quality were examined using the RoboFlag simulation environment. Environmental uncertainty and knowledge of the opponent's strategies were manipulated factorially. Measures of mission effectiveness and decision quality were obtained along with subjective assessments of situation awareness and workload. Results are discussed in terms of decision quality as expressed by the tactics assigned to the operator's robots, and with respect to the mission outcome for each trial. Further, the number and appropriateness of re-tasking orders and the effects of unreliable information are addressed.

COGNITIVE ENGINEERING AND DECISION MAKING: Expertise and Macrocognition Analysis

The Effects of Prior Knowledge on Strategy Development Performance BIBAFull-Text 453-457
  Jeffrey T. Hansberger
The types of strategies individuals use and how they use them over time potentially determines adaptability, their ability to learn, and their performance. The prior knowledge and experience people bring to a dynamic task can influence these task interactions. This study investigated the strategies used, strategy variability, performance, and learning over a 2-3 month time period in a complex, dynamic task environment between two groups of individuals that differed on their prior knowledge of the task domain of football coaching. The two groups displayed distinctly different patterns of strategy use, development, learning, and performance over time. One group focused on improving their domain knowledge base while the other refined their strategy repertoire and showed improved performance over time.
Models of Human Expertise as Blueprints for Cognitive Engineering: Applications to Landmine Detection BIBAFull-Text 458-462
  James J. Staszewski
Landmines pose a major military threat as well as a serious humanitarian problem. The difficulty of detecting buried landmines, especially modern landmines with minimal metallic content, contributes heavily to the problem. The two projects described here took a cognitive engineering approach to improve detection capability via development and implementation of scientifically principled operator training. Each analyzed and modeled the landmine detection skills of expert users of two different handheld detection systems, the PSS-12, the U.S. Army standard equipment, and the PSS-14, an advanced technology system under development at the time of this work. Model-based training programs were developed and tested. Both proved highly effective for developing detection skills, producing the greatest increases in detection rates against the most challenging targets. The US Army has adopted and now uses both programs. Results demonstrate the practical utility of information-processing models of expertise for designing instruction and developing important human skills.
Technology Integration Expertise Among Middle School Teachers BIBAFull-Text 463-467
  Judy L. Lambert
When technology is integrated effectively into classrooms there is strong positive impact on student achievement. However, there is still a great divergence between what enthusiastic advocates think technology will do for education and what is actually being accomplished. The primary objective of this study was to identify the concepts and knowledge that teachers who are experts in technology integration consider to be essential for successful technology integration, and to examine how these teachers characterize this conceptualization in their design and practice of instruction. The conceptual knowledge of these expert teachers was compared to the knowledge of teachers who are not technology experts to identify knowledge that should be highlighted in technology training sessions. Study findings indicate a significant difference in the knowledge organization of technology experts and novices with the experts focusing on conceptual issues such as challenges; technology as a stimulant to change in the learning environment; new opportunities; and effects of technology integration on the learning environment while novices tended to focus on lower level procedural skills required to use the technology.
Targeting The Right Level of Socio-Cognitive Analysis: Complex Problem Solving in High Performance Networks BIBAFull-Text 468-472
  Barbara Mirel; Nicholas Johnson; Jing Deng
Our study focuses on network engineers' experiences when they troubleshoot complex problems in distributed data and communication networks. Currently, these troubleshooters lack truly useful support for this complex problem solving. To identify socio-cognitive demands of this nonroutine troubleshooting, we conducted interviews with advanced network troubleshooters and analyzed transcripts of real time troubleshooting and post-mortem discussions among troubleshooters from diverse domains. Findings show that ad hoc cross domain collaborations are vital to the success of complex troubleshooting and that collaborators need better support for discussing responsibility in human and organizational terms and for recognizing strategic gaps, detailed issues and trade-offs they must negotiate for problem conditions.
Cognitive Impact Metrics: Applying Macrocognition During the Design of Complex Cognitive Systems BIBAFull-Text 473-477
  Brian M. Moon; Stephanie Wei; Donald A. Cox
Macrocognition is an emerging theoretical and methodological framework for describing cognitive work as it naturally occurs (Klein, Ross et al., 2003). It can form the basis for the design of complex cognitive systems that augment, rather than degrade, proficient performance. This paper presents a method for using macrocognition during design to anticipate how a complex cognitive system will impact cognition. We have developed a suite of metrics we call "Cognitive Impact Metrics" (CIM). Because they highlight the necessary features of and potential barriers to proficient cognitive performance, these metrics and their associated measures provide us with a framework in which we can generate predictions about where and how our system will enhance or hinder our performance. Application of CIM may be particularly useful in the design of systems where many potential applications must be culled down to a more manageable set of candidates.


Explorations in Cognitive Work Analysis: Analysis to Design BIBAFull-Text 478
  Gavan Lintern
The problem is not to match a display format to the mental models of the operators but to design an interface that forces operators to adopt a faithful mental model of the design constraints in a way they can directly manipulate the constraints so as to bring the system into the goal state and/or prevent it from entering dangerous states.
   Rasmussen (1995)
   The process of translating the products of cognitive analyses into an effective interface between workers and a work system has not been articulated as well as the analytic methods themselves. One can get the impression that the purpose of a cognitive analysis is to inform the designer about the nature of the work but that there are no design specifications that flow from the analysis. Nevertheless, cognitive analysis in general and Cognitive Work Analysis in particular, is promoted as a design process. Thus, we might inquire about the design principles that can be used to translate products of a Cognitive Work Analysis into artifacts that can support human-system integration. The papers of this session address this issue in different domains and for different types of applications. The diversity of domains and applications discussed in this session speaks to the generality of the design principles that can be used to transition from analytic product to design artifact.
Strategies for Bridging the Gap between Analysis and Design for Ecological Interface Design BIBAFull-Text 479-483
  John Hajdukiewicz; Catherine Burns
Creating effective graphic displays using Ecological Interface Design (EID) can be a challenging endeavor. Thus far, there has been little guidance in the literature to decrease the gap that exists between EID analysis and design. This paper presents strategies to help bridge this gap. First, a visual thesaurus provides alternative graphic objects and display formats for showing single variables, single-variable constraints, multivariate constraints, and structural constraints (i.e., means-ends, part-whole, and causal/topological relationships). Second, a number of lessons learned have been identified to improve efficiency in the process and provide further refinements to the display design. These strategies can decrease the effort involved in creating EID displays, but do not completely remove creativity from the design process. Future research includes further developing generic and industry-specific graphic forms for the visual thesaurus, while embedding effective design practices.
Analysing Cognitive Work of Hydroelectricity Generation in a Dynamic Deregulated Market BIBAFull-Text 484-488
  Penelope Sanderson; Rizah Memisevic; William Wong
Much electrical generation in the developed world is now conducted within deregulated energy markets, providing new layers of uncertainty for human controllers and new challenges for analysts wishing to understand and support cognitive work. In this paper we outline some of the challenges encountered when attempting to describe the work domain of hydroelectric power generation in a dynamic deregulated electricity market. The market component of the work domain analysis appears not to be readily amendable to breakdown as a familiar functional structure. Control task analysis is complicated by the fact that the human operator is the frontline, real-time, manager of business risk. Different epochs of planning may require separate functional structures.
Informing Design of a Command and Control Decision Support Interface through an Abstraction Hierarchy BIBAFull-Text 489-493
  M. L. Cummings; Stephanie Guerlain; Ellen J. Bass
The abstraction hierarchy can be used as a work domain analysis tool that provides a structured representation of a physical system under human supervisory control, and it aids in understanding complex human-machine interactions. The means-end relationships represented in the abstraction hierarchy provides a framework for highlighting areas that require knowledge-based reasoning through mapping processes and functions. These same abstract mappings can provide tangible insight into interface design relationships. We provide an example of using the abstraction hierarchy for this purpose in the development of a decision support tool for a military command and control interface. Allowing the abstraction hierarchy to inform interface design provides both an abstract and physical representation of system functional properties, which is especially critical in conceptualizing and designing an interface for a complex, time-pressured command and control domain.
On the Integration of Cognitive Work Analysis within a Multisource Information Fusion Development Methodology BIBAFull-Text 494-498
  Ann M. Bisantz; Galina Rogova; Eric Little
This research explored the means by which methods in cognitive engineering, namely, work domain analysis, could be used to provide input to the development of advanced information processing, or multisensor information fusion, algorithms. Specifically, a work domain analysis of an emergency management environment (in a post-earthquake context) was performed, and linked abstraction hierarchy models representing the emergency management and response system, the physical environment (e.g., buildings, transportation systems, civilians), and other goal directed agents (e.g., civilian responders and volunteers) were created. Outputs from that analysis (information requirements) were input to the design of the information processing algorithms, providing guidance as to the nature of information required by decision makers, which could be computed through fusion capabilities. This ongoing work thus presents an example of an integrated cognitive engineering/multisensor fusion methodology.

COGNITIVE ENGINEERING AND DECISION MAKING: Factors and Analysis in Command and Control

Perceptual and Cognitive Processes and the Movement of Combat Rifle Teams in Urban Terrain at Night BIBAFull-Text 499-503
  James B. Sampson; Michael J. Statkus; Robert J. Woods; Julie T. Weismantel; Frederick J. DuPont
Thirty-six infantry soldiers executed a series of exercises in a study of cognitive processes that influence combat tactical performance in urban terrain. Participants with varied levels of experience conducted nighttime missions to retrieve a hostage or valuable equipment. Teams were led by a Platoon Leader and Platoon Sergeant against a defending squad. Data were obtained from interviews, overhead videos, and questionnaires. Case-based evidence was collected on impact of site familiarity, military experience, and use of night-optical devices on performance. Comparisons with previous study show the effect of a number of variables on perceptions, planning, and tactical movement. Theoretical frameworks for interpreting data include theories of Control, Recognition Primed Decision Making, and Multiple Resources. Each of these account for some aspect of actions observed and the impact of prior experience, sensory-perceptual clarity, focus of attention, and time pressure on individual and unit performance.
Organizational Structure, Information Load, and Communication in Navy Teams BIBAFull-Text 504-508
  Keith Baker; Elliot E. Entin; Katrina See; Kevin Gildea; Bonnie Baker; Stephen Downes-Martin; Jon Cecchetti
Models developed to study and evaluate innovative organizational structures predict organizations with an intelligence, surveillance, and reconnaissance (ISR) coordinator will be superior in performance to organizations without such a coordinator, especially when information load is high. We examined the effect of the presence or absence of an ISR coordinator and information load on mission performance employing a moderate fidelity man-in-the-loop simulation. Counter to the modeling predictions the organization with an ISR coordinator was not superior in performance to an organization without an ISR coordinator. However, analysis of the Email/Intel message traffic showed organizations with an ISR coordinator to be superior in situation assessment and awareness. When these latter results are coupled with results showing a steep and significant improvement curve between trials 1 and 2 for the organization with an ISR coordinator, we surmise that if teams are given more practice and familiarization with novel organizations, empirical results will confirm the model predictions.
Shared Mental Models in Military Command and Control Organizations: Effect of Social Network Distance BIBAFull-Text 509-512
  John Graham; Mike Schneider; Aaron Bauer; Katie Bessiere
This paper presents an investigation on the relationship between social network distances and shared mental models in military command and control organizations. Previous research has shown that physical distance is the gold standard for high performance (Olson & Olson, 2000). However, social network distance may be equally or more important, as social network graphs inherently take into account the group's context and environment (Krackhart, 1994). We conducted this research on a new 56-member command and control organization using computer-based collaborative tools as they engaged in a five day simulation exercise. As military command and control organizations are difficult to evaluate based on outcome and performance, we chose shared mental models as a proxy. We hypothesized that in a command and control organization, social network distance and physical distance are independent of one another. Further we hypothesized that social network distance would be a predictor of mental model congruence. We found that there is a very weak positive correlation between social network distance and physical distance. Further, we found that, controlling for physical distance, social network distance is a predictor of mental model congruence. This research validates that high frequency of communication, mediated by computer based collaborative tools, can effectively generate shared mental models.
Neural Net and Discrete Event Simulations of C2 Performance in Army Tocs BIBAFull-Text 513-517
  Sam E. Middlebrooks
This project examines command and control (C2) from a system level viewpoint to study the way Tactical Operations Centers (TOC's) operate and then translates those observations into validated computer simulations using a methodological framework. This approach provides the ability to model TOC operations in a way that not only includes the individuals, work groups and teams in it, but also all of the other hardware and software systems and subsystems and human-system interfaces that comprise it as well as the facilities and environmental conditions that surround it. Datamining procedures, including neural network simulation, are used to screen raw data from naturalistic observation of TOC operations to identify significant relationships for follow-on analysis. Discrete event simulations then utilize mathematical relationships from the neural network analysis to describe TOC operations in a way that can be used for evaluations of new and proposed TOC Systems. The intent of this project is to develop a framework of techniques and procedures that are based upon empirical methods but are usable in real world, uncontrolled environments which can only be approached with naturalistic observation methods.
A Novel Integration of Human Factors Methods to Analyse C4I Activity; A Chemical Incident Case Study Carried out with the Uk Fire Service BIBAFull-Text 518-522
  Guy H. Walker; Chris Baber; Neville A. Stanton; Salmon Paul; Damian Green; Richard McMaster
This paper presents an integration of seven human factors techniques into a comprehensive task and knowledge based methodology. The case study demonstrates that the proposed methodology can be successfully applied to the analysis of command and control (C4) teams and shows how each of the methods interface with each other to produce; a process based overview using an enhanced form of Operation Sequence Diagram (OSD), and a knowledge based overview using a Propositional Network. This paper demonstrates how the methodology enables key constructs within C4 domains to be captured for the purpose of designing future systems.

COGNITIVE ENGINEERING AND DECISION MAKING: Human Control of Teams of Robotic Vehicles: Exploring the Limits of the Possible

Human Control of Teams of UnmannedRobotic Vehicles: Exploring the Limits of the Possible BIBAFull-Text 523-527
  Jean MacMillan; Christopher L. Johnson; Michael P. Linegang; Christopher A. Miller; Raja Parasuraman; Emilie M. Roth
Robotic vehicles under human control are currently being used for exploration and surveillance in variety of environments that are inaccessible or dangerous for humans. The operation of such vehicles is currently labor intensive, however, with multiple operators typically required for each vehicle employed. This panel reports on progress being made in the control of teams of robotic vehicles by much smaller teams of human operators through the combination of sophisticated automated control algorithms and human supervision. The goal is mixed initiative control -- flexible and dynamic shifting of responsibility between humans and automation as required over the course of a mission. The panel will discuss cognitive engineering approaches to the design of a mixed initiative system for multi-vehicle robotic control including development and experimental testing of prototype interface designs, workload modeling, and optimal team design. The strengths, limitations, and potential complementarity of these approaches will be discussed.


Too Much, Too Little or Just Right: Designing Data Fusion for Situation Awareness BIBAFull-Text 528-532
  Geoffrey B. Duggan; Simon Banbury; Andrew Howes; John Patrick; Samuel M. Waldron
Many operators within the battlefield find themselves unable to process all the data presented to them in the limited time available. Data fusion provides a means of reducing their workload, but can also reduce system transparency. Thus, either too much or too little fusion can lead to reduced operator situation awareness. A framework is proposed that incorporates a role for more sophisticated psychological theory when attempting to understand the consequences of data fusion technologies on SA. Four key questions are identified: How should the level of certainty in fused information be presented? How much does it cost the operator to "drill-down"? To what extent does data fusion inhibit representation change? Does data fusion ameliorate or exacerbate the consequences of interruption?
Automating Terrain Analysis: Algorithms for Intelligence Preparation of the Battlefield BIBAFull-Text 533-537
  Charles Grindle; Michael Lewis; Robin Glinton; Joseph Giampapa; Sean Owens; Katia Sycara
Terrain information supplies an important context for ground operations. The layout of terrain is a determining factor in arraying of forces, both friendly and enemy, and the structuring of Courses of Action (COAs). For example, key terrain, such as a bridge over an unfordable river, or terrain that allows observation of the opposing forces line of advance, is likely to give a big military advantage to the force that holds it. Combining information about terrain features with hypotheses about enemy assets can lead to inferences about possible avenues of approach, areas that provide cover and concealment, areas that are vulnerable to enemy observation, or choke points. Currently, intelligence officers manually combine terrain-based information, information about the tactical significance of certain terrain features as well as information regarding enemy assets and doctrine to form hypotheses about the disposition of enemy forces and enemy intent. In this paper, we present a set of algorithms and tools for automating terrain analysis and compare their results with those of experienced intelligence analysts.
Sensor Noise and Ecological Interface Design: Effects on Operators' Control Performance BIBAFull-Text 538-542
  Olivier St-Cyr; Kim J. Vicente
We studied the impact of sensor noise on operators' control performance using an Ecological Interface Design (EID) display with a representative thermal-hydraulic process simulation. A number of studies have shown that EID improves the performance of operators. However, no studies have assessed the effects of the presence and magnitude of sensor noise on interfaces based on EID. We hypothesized that as the magnitude of sensor noise would increase, performance would worsen for both EID and non-EID operators, although performance of the EID group would not be worse than that of the non-EID group. Our results show that EID participants performed significantly better than non-EID participants when dealing with industry representative sensor noise. When the magnitude of sensor noise was randomly increased, no differences were observed between the two groups. These results have important consequences for the applicability of the EID framework in industrial settings.
Collaboration with Ecological Interface Design BIBAFull-Text 543-546
  Angela Garabet; Catherine M. Burns
Ecological Interface Design (EID) has been shown to be an effective design approach for building single-operator interfaces for complex systems. However, in such systems, operators typically are also a part of a team. An experiment was conducted to examine the effect of EID on collaboration. Teams of two operated a feed water simulator, DURESSj, through a series of scenarios given either the EID interface or the Non-EID interface. It was found that there was no penalty to using EID, as scenario completion times with the EID interface were equivalent to the Non-EID interface. Indeed, EID operators demonstrated evidence of more robust control and reported significantly lower mental workload especially when dealing with system faults.
New Approaches to Overcoming E-Mail Overload BIBAFull-Text 547-551
  Shawn A. Weil; David Tinapple; David D. Woods
As e-mail has become the preferred medium for communication, the inbox and mail folders become one hub for organizing activities and schedule. The combination of a natural rise in message volume and the large amounts of unsolicited bulk messages (spam) have led some to suggest that the usefulness of e-mail is at an end; users feel overwhelmed by the sheer numbers of individual messages and the effort to manage the inbox. This paper frames the issue of e-mail/message overload as a specific example of data overload and uses previous results to suggest three design concepts -- cognitive buoyancy, e-mail constellations, and the intelligent subject line -- for use in e-mail.


Team Stress and Performance: Implications for Long-Duration Space Missions BIBAFull-Text 552-556
  Judith Orasanu; Ute Fischer; Yuri Tada; Norbert Kraft
Interpersonal tensions during long-duration space missions can endanger mission success by preventing crew cooperation or by inducing errors. Crew friction in past U.S.-Russian missions drives home the need to understand how interpersonal stresses precipitate crew breakdowns. Most team research of the past decade has focused on the cognitive and communication aspects of team performance. The present study addressed the interpersonal aspects as well. A computer-based laboratory was created to study team problem solving under stressful conditions. Twelve teams of four males (aged 25-45) participated in six 75-minute search and rescue "missions." A path model showed that level of mission success reflected degree of team collaboration, which was driven by both group level and individual factors. High levels of team cohesion, a helpful base-station leader, feelings of acceptance, and provision of interpersonal support were associated with high levels of collaboration. Implications of these findings for team composition and training will be discussed.
Time in the Control of a Dynamic Environment BIBAFull-Text 557-561
  Marie-Eve Jobidon; Robert Rousseau; Richard Breton
Because of their intrinsic nature, it is fundamental to consider the temporal dimension when studying control in dynamic situations. However, the temporal aspect is often taken for granted and not accounted for in cognitive or control models. The present study aims to understand the role of temporal estimation in the control of a dynamic task, within the Contextual Control Model (COCOM). Particularly, the main objective is to evaluate how time pressure influences the estimation of available and required time. A dynamic situation, which includes two sub-tasks, the pursuit of a target and the avoidance of hostile contacts, is used. Results show that both available and required estimated times, as well as performance, decrease with increased time pressure. These findings suggest that when faced with a high level of time pressure, people adapt their strategies by giving up an offensive mode of control, in favor of a more defensive one, earlier in the game.
Measurement of Cognitive Load Dynamics in a High-Speed Oppositional Task BIBAFull-Text 562-566
  Herbert N. Maier
Attentional dynamics in complex, high-stakes environments are shown with the additional challenge of a live opponent. A traditional martial arts task-model offers a training structure that integrates complex state, cue and option knowledge for access under time-pressure. Participants challenge each other iteratively within a network of linked tasks (~1 cycle/second). Input to each person resembles real-world unpredictability, which is not truly unstructured. Interactions among four performance dimensions reveal individual differences in management of cognitive loading. Results also show a clear dynamic balancing the total load managed by each of 10 dyads, defining opponents as a system, pushing each other toward cognitive overload and failure. The task's dimensionality and self-organization generates individualized training. This research offers points of interest to situation awareness and cognitive systems, individual differences and training.
Measurement of Taskload and Performance in a Dynamic Multi-Task Experiment BIBAFull-Text 567-570
  Brian R. Levinthal; Esa M. Rantanen
This paper discusses an experimental paradigm for measuring human performance under time pressure. Participants were presented with four simultaneous number-entry tasks. Entry could occur only within a discrete window of opportunity, represented visually by a target range within a variable-speed progress bar. Participants could view only one task at a time, thus performance required scanning and sampling of all four tasks. Sampling behavior (mouse movements to the vicinity of one of the four tasks) was manipulated via access effort; blocks of trials presented either a half or full second lag before a target task would become visible. Participants' performance was evaluated by the proportion of responses completed within the required window of opportunity as well as the proportion of a window of opportunity that elapsed before the onset of a response. Results indicate a decrease in such performance as a result of display lag manipulation. The potential for the use of this paradigm in developing predictive measures of performance is discussed.
Investigating Dynamic Environments using the Game of Diplomacy BIBAFull-Text 571-575
  Gordon J. Gattie
Cognitive engineers are constantly exploring human performance in naturalistic environments. Recently, cognitive engineering techniques have been utilized by the intelligence community as potential tools to improve human performance. In this study, the game of Diplomacy was used as a testbed for applying Brunswik's Lens Model to dynamic environments containing multiple agents. The game of Diplomacy is based on the diplomatic relationships between the seven Great Powers of Europe just prior to the start of World War I. In contrast to many two-player strategic games, the game of Diplomacy includes seven independent players moving simultaneously, players creating and breaking alliances, and an historically-based playing board; yet one game can be completed in a few hours. This study, which was based on archival data, compares the judgmental policies of seven decision makers from two completed games. Limitations of this study and possibilities for using Diplomacy variants for future research are discussed.
A Roadmap for Cognitive Engineering in Systems Engineering BIBAFull-Text 576-580
  Craig A. Bonaceto; Kevin J. Burns
We are concerned with three challenges in the design of military Command and Control (C2) systems, namely: the demand for "smaller" organizations, the demand for "better" coordination (human-system, human-human and system-system) and the demand for "faster" execution. Driven by these demands, we performed a survey of Cognitive Engineering techniques with an eye towards how they can improve Systems Engineering efforts. This paper outlines our three challenges (smaller, better, faster) and reviews three successful applications by other Cognitive/Systems engineers faced with similar challenges. The applications employ Computational Cognitive Modeling (to address a demand for smaller), Cognitive Work Analysis (to address a demand for better) and Goal-Directed Task Analysis (to address a demand for faster). These three successes provide a practical roadmap for using Cognitive Engineering methods to address Systems Engineering problems in C2 as well as other domains.
A New Look at the Dynamics of Human-Automation Trust: Is Trust in Humans Comparable to Trust in Machines BIBAFull-Text 581-585
  Poornima Madhavan; Douglas A. Wiegmann
The trust placed in automated diagnostic aids by the human operator is one of the most critical psychological factors that influences operator reliance on decision support systems. Studies examining the nature of human interaction with automation have revealed that users have a propensity to apply norms of human-human interpersonal interaction to their interaction with 'intelligent machines'. Nevertheless, there exist subtle differences in the manner in which humans perceive and react to automated aids compared to human teammates. The present review is focused on comparing the process of trust development in human-automation teams with that of human-human partnerships, specifically in the context of dyads that constitute a primary decision maker and either a human 'advisor'or an intelligent automated decision support system. A conceptual framework that synthesizes and contrasts the process of trust development in humans versus automation is proposed. Potential implications of this research include the improved design of decision support systems by incorporating features into automated aids that elicit operator responses that mirror responses in human-human interpersonal interaction.
Reliability and Age-Related Effects on Trust and Reliance of a Decision Support Aid BIBAFull-Text 586-589
  Julian Sanchez; Arthur D. Fisk; Wendy A. Rogers
Trust has been identified by previous research as a key determinant of automation reliance and usage (Lee & Moray, 1992). One factor that may affect trust and reliance on automation is the reliability of the automation (Parasuraman 1993; Riley, 1996). The effects of automation reliability and age on perceived reliability, trust, and reliance were investigated. A driving-like task was created and the reliability of the automation was manipulated by generating three levels (100%, 80% and 60%). Automation was present in the form of a decision support system that indicated the state of the gauges. Results indicated that high levels of automation reliability lead to increased reliance and higher subjective levels of trust. There were age-related effects on the ability to perceive the reliability of the automation and levels of trust where older adults were more sensitive to the change between 80% and 60% reliability than the younger adults.
Closing the Loop of an Adaptive System with Cognitive State BIBAFull-Text 590-594
  Michael Dorneich; Stephen Whitlow; Patricia May Ververs; Jim Carciofini; Janet Creaser
This paper describes an adaptive system that "closes the loop" by utilizing a real-time, directly sensed measure of cognitive state of the human operator. The Honeywell Augmented Cognition team has developed a Closed Loop Integrated Prototype (CLIP) of a Communications Scheduler, for application to the U.S. Army's Future Force Warrior (FFW) program. It is expected that in a highly networked environment the sheer magnitude of communication traffic could overwhelm the individual soldier. The CLIP exploits real-time neurophysiological and physiological measurements of the human operator in order to create a cognitive state profile, which is used to augment the work environment to improve human-automation joint performance. An experiment showed that the Communications Scheduler enabled higher situation awareness and message comprehension in high workload conditions. Based solely on cognitive state, the system inferred a subject's message comprehension and repeated unattended messages in the majority of cases, without yielding an unacceptably high false alarm rate.
On the Application of Cognitive Work Analysis to the Development of a Commercial Investment Software Tool BIBAFull-Text 595-599
  Marvin J. Dainoff; Charles A. Dainoff; Larry McFeeters
Principles of cognitive work analysis were directly applied to the conceptualization and design of a web-based software tool for investment analysis. The investment philosophy known as fundamental analysis is concerned with the intrinsic value of a company compared with its stock price. The means-end abstraction hierarchy was critical in characterizing the work domain of the fundamental analyst and allowed an ecological interface on the domain to be constructed. This resulted in a patentable software product which is now on the market.
Managing Metadata in Collaborative Command and Control Analysis BIBAFull-Text 600-604
  Par-Anders Albinsson; Magnus Morin; Mirko Thorstensson
When analyzing field trials to examine command and control, there is a great need for means of presenting, coordinating, exploring and analyzing large amounts of data captured from multiple sources. The products of this analysis include insights, reflections, questions, and hypotheses. From an epistemological point of view, it is crucial to maintain a solid chain of reasoning from the data captured in the field, through the presentation formats used in the analysis process, and to the results of the analysis delivered to the clients. To this end, we present the Metadata Workbench, which manages metadata in command and control analysis. This analysis tool embeds metadata in contextual information, coordinates them in time, and links them to the supporting data. Using the tool, multiple analysts, experts, and researchers can exchange comments on both data and metadata in a collaborative and explorative investigation of a complex scenario. The tool is implemented as a component in the Mind framework and is demonstrated using data from distributed tactical operations.
Exploring Cognitive Work within a 911 Dispatch Center: Using Complementary Knowledge Elicitation Techniques BIBAFull-Text 605-609
  Ivanna S. Terrell; Michael D. McNeese; Tyrone Jefferson
This study evaluates the differences in user information acquired from scenario-based versus non scenario-based knowledge elicitation for the design of 911 dispatch simulations. During the non-scenario condition, participants answered probe questions concerning their work activities and emergency response procedures. During the scenario-based condition, participants were presented with an emergency scenario and described the necessary steps required to respond to the situation. Preliminary analysis implies that information derived from non scenario-based knowledge elicitation may focus more upon the defined protocols of workgroups whereas information gathered from scenario-based knowledge elicitation may be more concerned with procedures and interactions that are unique to a certain workgroup. Results suggest that the use of scenario-based knowledge elicitation is more likely to allow designers to tailor simulations that conform to the unique culture of an emergency dispatch center workgroup than non scenario-based knowledge elicitation.
Collaborative Tools and Shared Mental Models BIBAFull-Text 610-613
  Cheryl Bolstad; Mike Schneider; John Graham; Cleotilde Gonzalez
This paper reports on an experiment conducted to measure collaboration tool usage and shared mental models in Army Command and Control. Several teams of soldiers participated in a two-week simulation experiment. During the simulation, the run was stopped and participants completed a 5-minuted on-line questionnaire in which they were asked to rate their workload and other teammates workload as well as provide information on the collaboration tools used during the last hour of the exercise. Shared mental models was measured using congruency between each person's rating of their own workload and their teammates perception of their workload. Overall, using the same collaboration tool, irrespective of the tool type, to communicate between team members lead to higher shared mental models.
Experimentation for Envisioned Worlds: Understanding the Limitations of the Military after Action Review as Experimental Data BIBAFull-Text 614-618
  Jodi Heintz Obradovich; John Graham; Mike Schneider; Cleotilde Gonzalez; Robert Harder
The research reported here was conducted to explore the efficacy of using the military After Action Review (AAR) process as a data collection methodology. During a weeklong U.S. Army experiment, we investigated, by means of a periodically administered questionnaire and an end-of-day log, the interactions participants reported having with other team members. When comparing the results of these tools, we found strong tendencies of the primacy and recency effects. These findings are important to researchers working in military command and control experimentation settings where the AAR is a commonly used data collection mechanism. This paper identifies data collection practices that can help avoid potential difficulties when using end-of-day retrospective reports as an experimental methodology.
Crowd Behavior Observation for Military Simulation BIBAFull-Text 619-623
  Carlotta M. Boone; Ryland C. Gaskins; Mikel D. Petty
Observations are frequently used to examine naturally occurring behavior. The researchers used this tool to determine what types of behaviors crowds exhibited and the degree of aggression expressed by the crowds. Footage of the 1999 WTO protest in Seattle was examined and coded for 55 behaviors. Of the observed behaviors standing on an elevated platform, chanting, yelling and shouting, and raising flags were the most frequent behaviors. Overall, most of the action was moderately aggressive. Highly aggressive behaviors such as fighting and attacking police officers composed only 1% of the observed behaviors. A similar observation was conducted of an anti-war protest in New York. This observation found comparable results of prevalent nonviolent behaviors. The findings from these studies along with those obtained from interviews of returning military officers will be used to develop a model for simulation of crowd behaviors.
Mental Rotation of Objects in an Airport Security Setting BIBAFull-Text 624-626
  Justin Fox Morgan; Shawn Stafford; Razia Nayeem; Aaron Pepe
The role of mental rotation in the airport security screening task was examined. 13 participants were asked to detect a handgun which was shown embedded in an x-ray image similar to what a baggage screener would see. The weapon was shown to the participant in 8 different rotations for 2 different perspectives (facing right or left for each rotation). The results of the experiment produced the classic inverted V response time function curve. The data suggest that mental rotation can be applied to complex stimuli found in detection task such as the airport security domain.
An Application of the Akadam Approach to Intelligence Analyst Work BIBAFull-Text 627-630
  Erik S. Connors; Patrick L. Craven; Michael D. McNeese; Tyrone Jefferson; Priya Bains; David L. Hall
This paper emphasizes the use of cognitive task analysis to gain significant insight into the unique domain of intelligence analysts, how intelligence analysts view this domain, and how this domain can be replicated in a controlled simulation environment in which innovative tools and procedures can be empirically tested. Details of two comprehensive knowledge elicitation sessions involving intelligence analysts are provided as an example of using the Advanced Knowledge Acquisition and Design (AKADAM) methodology to obtain contextually relevant information for use in developing a homeland defense-oriented simulation/experimental task. Several distinctive characteristics of intelligence analyst functionality were discovered, including the multi-source integration of relevant information, complex cognitive analysis, and team collaboration in decision-making. Additional themes such as social interaction and the limitations of current analysis tools were identified.
A Distributed Cognition Simulation Involving Homeland Security and Defense: The Development of Neocities BIBAFull-Text 631-634
  Rashaad E. T. Jones; Michael D. McNeese; Erik S. Connors; Tyrone Jefferson; David L. Hall
This paper describes a scaled-world simulation developed to conduct empirical research on team cognition, communication, and decision-making within a distributed environment. The NeoCITIES simulation is an advancement of the CITIES task, which was designed to study group decision-making within a command, control, and communications (C) setting (Wellens & Ergener, 1988). Studying group decision-making is a two-fold problem involving team cognition and team communication. According to McNeese (2003), team cognition is constructed through distributed and emerging activities via several sources. A majority of studies examining distributed decision-making have involved militaristic, battlefield engagement, or urban warfare settings. In that same spirit, NeoCITIES was designed for emergency crisis management teams undergoing terrorist attacks within a college-town. Thus, NeoCITIES is a new and operationally relevant scaled world that emulates the complexities and emergent decision-making attributes resident in a 9/11-type of terrorist scenario. Through the use of NeoCITIES, we anticipate the assessment of a number of cognitive tools to support distributed cognition (e.g., problem-based decomposition) as well as advancing adaptive intelligent interfaces.
A Computerized Text Analysis can Detect Deception BIBAFull-Text 635-639
  Mary T. Dzindolet; Linda G. Pierce
Detecting deception is an important skill, yet reviews of the psychological literature on the detection of deception typically find accuracy rates between 45 and 60% (cf., DePaulo & Friedman, 1998). A computerized text analysis, the Linguistic Inquiry Word Count (LIWC), offers one technological solution. Newman et al. (2003) used the LIWC to detect deception in five studies. Deceptive communications were characterized by fewer first person singular pronouns, third person pronouns, and more negative emotion words. In this study, 49 students delivered a deceitful and a truthful communication regarding their preference for music. Results from the 2 (importance of music in participants' life: high or low) x 3 (communication medium: type, write, or talk) x 2 (communication type: lie or truth) design indicated that technological tools may be useful in detecting deception; however, communication medium and topic importance mediate the relationship.
Electronic Checklists in the Context of B-2 Pilot Decision Making BIBAFull-Text 640-644
  Andrea E. Snead; Laura G. Militello; Jill A. Ritter
Anticipating the impact of the transition from paper checklists to electronic checklists is of significant interest to the US Air Force as they consider the development of electronic checklists for use in military aircraft. This paper describes a limited cognitive task analysis (CTA) conducted with B-2 pilots, exploring the current use of paper checklists and other reference materials during flight, particularly during emergency procedures. Results include a description of the reference materials currently used, a discussion of their use in the context of workflow, a depiction of decision flow, and a list of recommendations for designers interested in developing electronic checklists for military aircraft use.
Confirmation Bias in Scientific Reasoning: The Roles of Gender, Perceived Competence and Actual Competence BIBAFull-Text 645-648
  Tatiana T. Ballion; Valerie K. Sims; Sidra I. Van de Car
It has been previously shown that there is a relationship between level of metacognitive ability and estimation of ability for largely verbally-based tasks; those with lessened facility for the task tend to overestimate their aptitude relative to their peers (Kruger & Dunning, 1999). This study examines this effect for a task of mechanical ability, where subjects (n = 69) were given an abbreviated Bennett Mechanical Comprehension Test (BMCT) to establish a level of competency. Participants were then asked to estimate a grade for their performance, as well as the relationship between their hypothetical grade, and the grades of others. Participants then explained the solution to one of the problems, and their explanations were coded for degree of bias towards confirmation versus disconfirmation. Females on the high and low ends of skill were more likely to use a confirmatory approach when there was a discrepancy between Perceived Relative Competence, and Actual Competence.
Impact of Hidden Profiles on Distributed Cognition in Spatially Distributed Decision-Making Teams BIBAFull-Text 649-652
  Tyrone Jefferson; Lori Ferzandi; Michael McNeese
This study continues research from McNeese (2000) and was designed to examine the effects of hidden knowledge profiles on perceptually anchored team cognition and knowledge transfer in distributed teams. Previous work showed that individuals in perceptually anchored distributed teams were able to quickly access applicable knowledge, then transfer that knowledge to answer similarly situated problems. Perceptual anchors provide the basis for formulating team mental models, which can be used to assess situations and resolve differences in individual, unique knowledge. In the present experiment, it was again hypothesized that individuals working in perceptually anchored distributed teams would be better able to transfer knowledge, than teams without anchors. It was also hypothesized that perceptually anchored distributed teams would be better able to share uniquely held information, make better decisions, identify information discrepancies, and overcome the presence of hidden knowledge profiles better than non-perceptually anchored teams. Preliminary findings are discussed.


The Designer'S Situation Awareness Toolkit: Support for User-Centered Design BIBAFull-Text 653-657
  Debra G. Jones; Mica R. Endsley; Mark Bolstad; Gil Estes
Designing systems to support SA involves three phases: an analysis of SA requirements, the application of SA-oriented design principles, and the measurement of SA during design evaluation. The Designer's Situation Awareness Toolkit (DeSAT) provides support to the designer for each phase of this process through both tutorials and application specific tools. The tutorials cover the Goal Directed Task Analysis (GDTA) methodology for delineating SA requirements, SA oriented design principles, and the Situation Awareness Global Assessment Technique (SAGAT) methodology. The application specific tools include a tool for documenting GDTAs, a Checklist tool to assist designers in evaluating how well a design concept has met the relevant SA requirements, a Design Guidance application, and a tool for creating and administering SAGAT queries (Super SAGAT). Through these tools, DeSAT provides a comprehensive approach for improving the designer's ability to create designs based on sound SA oriented design principles.
A Process Tracing Approach to the Investigation of Situated Cognition BIBAFull-Text 658-662
  Lawrence G. Shattuck; Nita Lewis Miller
Technologists and human factors practitioners tend to approach the measurement of situation awareness from different perspectives. Technologists compare the difference between the data available in the environment with what has been detected by the sensors built into a system. Human factors practitioners focus on perception and cognition to the exclusion of the technological parts of the system. The authors propose a Dynamic Model of Situated Cognition and use it as a framework for analyzing both the technological and human aspects of a complex system. They employ a process tracing method in the analysis of a high fidelity military command and control (C2) simulation. Their results indicate that the model and the process tracing method are effective ways in which to investigate the development of situated cognition in complex systems. In addition, their results have important implications for designers of software, hardware, and training systems.
Situation Awareness in a Networked Virtual Submarine BIBAFull-Text 663-667
  Sam Huf; Han Tin French
This paper concerns human factors that might impact the success of future maritime defense operations. In such operations, extensive networking is likely to allow large amounts of information to be shared between headquarters, ships, submarines and aircraft. Military planners anticipate that this will enhance situation awareness for their forces. Researchers at Australia's Defence Science and Technology Organisation are studying this issue using a synthetic environment (a game play simulation involving a manned virtual submarine operating within a computer generated scenario). The initial focus of this work has been to identify appropriate metrics with which to monitor performance. Here we present an attempt to employ objective situation awareness metrics. Despite some technical problems, a number of interesting findings suggest that there may be a trade off between the accuracy of operator understanding and the size of the field of view of networked sensors.
Pc-Based Tools to Improve Infantry Situation Awareness BIBAFull-Text 668-672
  Laura D. Strater; Justus P. Reynolds; Laurie A. Faulkner; D. Kelby Birch; John Hyatt; Scott Swetnam; Mica R. Endsley
It is widely recognized that Situation Awareness, SA, provides the foundation for decision making and action in numerous domains. As such, this research focused on developing a PC-based tool for training SA in Infantry Platoon Leaders. This Infantry Situation Awareness Training (ISAT) program developed two modules targeted at enhancing SA in Infantry Platoon Leaders. The SA Planner teaches time management and task prioritization skills, while the SA Trainer focuses more globally on developing knowledge bases and understanding the information requirements necessary to develop SA. Validation testing was conducted by giving the SA Trainer to a group of Royal Norwegian Naval cadets prior to combat fatigue exercises. Results suggested possible performance differences between cadets trained with the tool and those who were not. Additionally, trained cadets indicated that they expended more mental effort predicting what would happen next (level 3 SA) and determining how to best meet their mission goals.


Dynamical Perspectives on Team Cognition BIBAFull-Text 673-677
  Jamie C. Gorman; Nancy J. Cooke; Preston A. Kiekel
A theoretical perspective based on dynamical systems theory is applied to the concept of team cognition. Important postulates based on this perspective include a division of labor based on the elements of information involved in performing a team task, as well as the notion of coordination among information elements occurring through elemental couplings via a coupling medium. These features of our perspective are outlined, with the important notion of mediational means receiving the most attention. The dynamics of discourse-based mediation are considered in light of empirical data involving changes in the content of discourse over time in an uninhabited air vehicle reconnaissance task.
Using Pathfinder to Generate Communication Networks in a Cognitive Task Analysis BIBAFull-Text 678-682
  Steven M. Shope; Janie A. DeJoode; Nancy J. Cooke; Harry Pedersen
As part of a cognitive task analysis performed in the initial design stage of developing an Unmanned Aerial Vehicle (UAV) operations center, we used Pathfinder to generate communication networks based on four subject matter experts' (SMEs') understanding of the typical communications that occur in different task scenarios (i.e., a strike operation versus a non-strike operation). SMEs provided ratings on three dimensions of communication for each pair of ten team members. Dimensions were 1) importance, 2) volume, and 3) diversity of communications. We developed two methods for merging the ratings of importance and volume into a single network in order to simultaneously represent both dimensions. This application of Pathfinder has allowed us to 1) quantify the extent to which the SMEs conceptualize communications in the same way and 2) generate surrogate communication networks when it is impossible to monitor actual communications.
Measuring Speech Flow of Co-Located and Distributed Command and Control Teams During a Communication Channel Glitch BIBAFull-Text 683-687
  Preston A. Kiekel; Jamie C. Gorman; Nancy J. Cooke
Team cognition can be observed in the flow of communications among team members. This is shown in the context of a simulated unmanned aerial vehicle ground control station. Automatic measures of low-level team communication flow were used to assess high-level constructs of team cognition. Measures show support for the expected results of manipulations in this task. Co-location and channel degradation effects were successfully predicted by CHUMS, ProNet, and a cross-correlation function-based Dominance measure. Results grant concurrent validity to the measures, and highlight substantive effects of the manipulations. In particular, in geographically distributed teams, communication patterns are less stable, and the route planner exerts less communicative influence. Some co-location effects drop with task experience. During a mission containing a five-minute one-way communication channel cut, all teams communicate more like distributed teams, and team members do create alternate pathways to retain information flow.
Cognitive Analysis Methods for Control of Multiple Robots: Robotics on 5 A Day BIBAFull-Text 688-692
  Roger A. Chadwick; Douglas J. Gillan; Dominic Simon; Skye Pazuchanics
Studies of a single operator controlling multiple robots were designed (1) to identify problems caused by perceptual and cognitive factors and (2) to propose interface concepts to reduce the problems. The studies used innovative techniques at extremely low cost. Existing artifacts, i.e., commercially-available video games played over local area networks, provided a rich source of data on control of one or multiple semi-autonomous entities with a minimum of development. Psychological theories regarding various attributes of robotic operation, including perception, navigation, motion control, and information display are embedded in such artifacts. Custom scenarios involving multiple robots controlled by a single operator were developed to facilitate switching between tasks and, in some cases, cooperative use of the multiple robots. Findings include data on navigation difficulty, task switching strategies, mode errors, and perceptual confusion regarding multiple viewpoints.
The Hunt for Situation Awareness: Human-Robot Interaction in Search and Rescue BIBAFull-Text 693-697
  Jennifer M. Riley; Mica R. Endsley
Robots are gaining acceptance as team members in complex task completion, though they must be directed or closely supervised by human operators. Effective interaction between operators and robots is dependent upon the operator's ability to develop situation awareness on the robot and environment. In teleoperation this requires the effective distribution of attention between remote activities and the local controls and interfaces. Limitations in attentional resources can limit SA on one or the other place, resulting in overall decreased system performance. We present observations made at a robot-assisted search and rescue exercise to describe common SA problems in vehicle control. This paper focuses on human-robot interaction and the role of SA in search operations. Key SA concerns observed and discussed include difficulties in robot localization, inadequate support for team operations and shared SA, workload in the visually demanding task, and poor integration of data at the interface.

COGNITIVE ENGINEERING AND DECISION MAKING: Tightening the Linkage of CSE and Software Systems Engineering

Tightening the Linkage of Cse and Software Systems Engineering BIBFull-Text 698-702
  Robert G. Eggleston; Catherine Burns; James Gualtieri; Gavan Lintern; Sterling Wiggins; Wayne Zachary


Time Design BIBAFull-Text 703-707
  Michael Hildebrandt; Esa M. Rantanen
The goal of this panel is to discuss theoretical and methodological approaches that may inform and support the design of temporal aspects of interactive systems. Time Design is an emerging research and development domain that emphasizes the functional, causal role of time in human control behavior. It draws on a diverse literature on time in cognitive psychology, psychophysics, sociology, computer science, engineering, Human Factors and HCI. Relevant research domains include heuristics and biases in temporal decisions, temporal aspects of human-automation interaction, planning and scheduling, visualisation of temporal information, and the timing of alarms and interruptions.

COMMUNICATIONS: Phones, Videoconferences and Automated Speech Systems

Conversational Re-Prompting in Natural Language Dialog BIBAFull-Text 708-711
  Harry E. Blanchard; Osamuyimen T. Stewart
Natural language understanding technology has reached a level of sophistication where it can be profitably employed in interactive voice response systems in telephony. This paper describes a call routing application, where callers state a request in unconstrained, natural speech. The system then routes the call to the correct destination system or attendant. If there is a problem in understanding, then the caller must be re-prompted. This paper looks at two cases of re-prompting in the second turn of dialog based on the caller's response in the first turn: (a) when a caller's initial request is to speak to a real person instead of stating the reason for their call, and (b) when callers are too vague in their initial response. A strategy of conversational re-prompting is introduced which fits into the greater naturalness of the dialog, and, we show, increases the performance of the system in terms of successful fulfillment of user requests.
Selecting a Voice Persona BIBAFull-Text 712-716
  Linda A. Roberts; Edward M. Silver; Leigh L. Rankin
The goal of this research was to evaluate and select an appropriate Voice Persona for BellSouth. A number of steps were utilized to make this selection, including: 1) Understanding how BellSouth and BellSouth voice services are currently perceived by our customers; 2) Defining desirable attributes that not only reflect our customers' needs but that also match the desired direction of the company; 3) Selecting voices for evaluation in the research study; 4) Designing and carrying out the research; and 5) Determining the preferred voice based on results of the study. Of five voices that were evaluated, a number of independent sources of data pointed to one of the voices as the preferred voice.
The Effectiveness of Tactile Cues in Cellular Phones BIBAFull-Text 717-720
  Christina C. Mendat; Jennifer L. Bell; Michael S. Wogalter
As cellular phones get smaller, there has been a concurrent reduction in the size of the control interface. Two studies examined whether tactile cues might facilitate dialing on small cellular phone keypads. The first study, a questionnaire administered to 289 individuals, suggested that people believe that tactile cues can benefit users of cellular phones. The second study, an experiment comparing dialing performance with vision precluded between two keypad-types (textured keys and smooth-keys), showed that performance in the former condition was better than that latter. Implications for cellular phone keypad designs are offered.
The Effect of Visual Momentum on Learning Hierarchical Menu Structures in Small Displays BIBAFull-Text 721-725
  Heather M. Olson; Leo Gugery; Robert Schumacher
Navigating through menu structures to access functions and search for information on small displays in cellular phones and other handheld devices is difficult. Visual momentum is a display technique that may help users integrate information across successive displays, and thus improve navigation performance for devices with small screens. This study investigated the effects of visual momentum and menu structure on the learnability of menus on small displays. Learnability was assessed using a trials-to-mastery measure. Mastery criteria regarding search time and errors were set during a pilot study and the number of trials it took for participants to meet these criteria during the Main Experiment were recorded. It was found that providing preview information in the display did not help users learn to navigate through hierarchical menus, while providing motion in the display did help.
Applying Multi-Attribute Utility Technique to Assess Alternative Communication Media BIBAFull-Text 726-730
  Han Frowein; Asbjorn Folstad; Trond Schliemann
This paper illustrates how MAUT (Multi-Attribute Utility Technique) can be used to assess the potential utility of communication media for end-users. Using ordinary telephony and face-to-face communication as reference media the utility of videoconferencing was assessed in three different communication tasks. The results showed that videoconferencing was generally more useful than telephony and less useful than face-to-face communication, and also that these differences depend on the specific nature of the communication activity. For instance, telephony was the best medium when it was necessary to lie. Such findings can be used as a basis for recommending which media are best suited for which aims and activities. A significant strength of the method is that it can quantify and combine not only how suitable a communication medium is for a particular purpose or activity, but also how important that purpose or activity is for the end-user.


User-Centered Evaluation of Multi-National Communication and Collaborative Technologies in a Network-Centric Air Battle Management Environment BIBAFull-Text 731-735
  W. Todd Nelson; Robert S. Bolia; Michael A. Vidulich; Anna L. Langhorne
Future command and control (C2) and air battle management (ABM) operations will undoubtedly be affected by the shift toward network-centric warfare (NCW), a concept of operations that relies upon a sophisticated information technology infrastructure comprising sensor, information, and engagement grids. It will be achieved through heightened shared situation awareness and real-time collaboration, which will require effective communication between coalition forces throughout the command chain. The present study provides an initial evaluation of communication effectiveness of persons from English-speaking countries with different dialects. In addition, an evaluation of collaborative interface technology for future ABM operations is presented. Together, these data provide an initial step in the characterization of communication challenges in future coalition operations and an assessment of the technologies that may be required to effectively share information and situation awareness in future ABM operations.
Natural Language Prompts for an Automated Call Router: Examples Increase the Clarity of User Responses BIBAFull-Text 736-739
  Benjamin A. Knott; Robert R. Bushey; John M. Martin
Speech-enabled interfaces are proving to be an effective option for service-center call routing applications. However, the effectiveness of a call routing application is dependent upon the speech recognizer correctly interpreting the caller's utterance. One approach to increase the clarity and routability of callers' initial requests is to provide examples within an open-ended prompt to provide context and guide caller's speaking behavior. Two experiments were conducted to investigate the effect of including examples in the opening prompt for a natural language call routing application. In both experiments, callers were asked to say the purpose of their call with an open-ended prompt. Half of the caller's were presented a prompt that contained examples, and half of the callers were presented with a prompt that did not contain examples. The results showed an advantage for the use of examples in terms of the percentage of routable caller utterances. The design implications for natural language prompts are discussed.
The Effect of Music Choice and Announcement Duration on Subjective Wait Time for Call Center Hold Queues BIBAFull-Text 740-744
  Benjamin A. Knott; Philip Kortum; Robert R. Bushey; Randolph Bias
An experiment explored the effect of Music Choice and Announcement Duration on the subjective wait time for a call center hold queue. Participants placed calls to a simulated call center and were placed "on hold." When participants were allowed to choose the type of music they listened to while on hold, they reported higher satisfaction with the wait time compared to a condition in which the callers had no control over the music type. There was also a significant effect for the hold queue announcement duration. The hold queue announcement is a brief message that informs caller that they are being placed on hold. The 'long' announcement resulted in more accurate estimations of on-hold wait time compared to the 'short' announcement which resulted in significant overestimation. These findings demonstrate potentially useful design methods for call centers to manage customer dissatisfaction due to hold queue delays.

COMPUTER SYSTEMS: Displays, Auditory and Visual

LCD vs. CRT: Effects on Performance of Office Work BIBAFull-Text 745-749
  Aaron Bangor
The present display technology transition in computing from CRT to LCD monitors poses many human factors research questions. In this study, computer monitor technologies were compared, using two CRT and two active-matrix LCD monitors under four lighting levels. Ten participants took part in a 4x4 within-subjects experimental design where they performed word processing, data entry, and web-browsing tasks. Results show that one of the LCD monitors was associated with poorer performance on the word processing task than an equivalent grouping of the other three monitors. Thus, it is concluded that active-matrix LCD monitors are capable of equitable performance with the traditional CRT technology, but it is uncertain whether the technologies themselves are equivalent. Lighting was another significant effect, with the dark (0 lux) and very bright (1200 lux) conditions causing poorer performance. There was no interactive effect between monitors and lighting. The battery of tasks used in this study, representative of office work, is also discussed.
Copious Electronic Text on Small Screen Interfaces: A New Method of Displaying Emails on Cell Phones BIBAFull-Text 750-753
  William Fitzpatrick; Shawn M. Doherty
Text information was presented to participants in a cell-phone sized display through a modified form of rapid serial visual presentation (RSVP) to investigate the effectiveness of comprehension of information on small displays. Thirty participants were exposed to combinations of three presentation speeds and three sets of line quantities. Results indicated that participants had optimal comprehension of text in 2-line or 4-line presentation of information at baseline reading speed.
Do Alternate Orientations of Navigation and Content Impact the Usability of Handheld Applications BIBAFull-Text 754-758
  Michael Catani; Danielle Gobert; Tom Tullis
This study explored the effect of displaying sideways navigation and content in graphical applications for handheld devices. Because these devices can be easily rotated during use, alternate orientations for screen elements may be acceptable. Participants performed tasks on prototypes emulating a wireless brokerage application presented on a Pocket PC handheld device. The prototypes differed in the orientation of the main navigation bar (top, sideways-left, sideways-right). Within each navigation condition, two prototypes displayed charts and tables in either a standard or sideways orientation. Results indicated that, as a function of navigation or chart and table orientation, there were no significant differences in task completion, time on task, number of screens navigated during tasks, or mean responses to a subjective evaluation questionnaire. These findings suggest that alternate presentations of navigation and content elements do not have a detrimental effect on the usability of handheld applications.
Effect of Speaker and Sampling Rate on MOS-X Ratings of Concatenative TTS Voices BIBAFull-Text 759-763
  James R. Lewis
The MOS-X is a recently-developed questionnaire used to evaluate the quality of artificial speech. In this experiment, participants listened to audio files produced by concatenative text-to-speech voices for the purpose of assessing the effect of Speaker and Sampling Rate on MOS-X ratings. The concatenative voices were developed from recordings of three different human speakers (code named AF, AM, and B) and produced using two different sampling rates (8 kHz and 22 kHz). Six independent groups of raters participated, one group for each combination of speaker and sampling rate. Analyses of variance indicated a significant main effect of Voice, but no significant main effect of Sampling Rate and no significant Voice by Sampling Rate interaction. The results indicate that independent groups of raters are sensitive to speaker differences in concatenative text-to-speech (TTS) voices, but not to differences in these sampling rates.
Designing Systems for the Creation and Evaluation of Dynamic Peripheral Soundscapes: A Usability Study BIBAFull-Text 764-768
  Bradley S. Mauney; Bruce N. Walker
Sonifications have proven useful as stand-alone displays and in bimodal audio-visual displays. Audio is powerful in a peripheral display due to its unobtrusive and omni-directional nature. This study examined the creation and usability of peripheral auditory displays or 'soundscapes' composed of ecological sounds. A system was created for dynamically generating soundscapes from a data source according to a threshold-based model. In this model, a percentage change in the data is mapped to an ecological sound that is played whenever that threshold has been met or exceeded. The system allows for the creation of soundscapes of arbitrary complexity, providing mechanisms for fading, relative gain, and random timing. With the system, a reference soundscape was developed for sonifying the stock market. This display was then presented to stock trader test participants as part of a usability evaluation.

COMPUTER SYSTEMS: Input for Handheld Devices

The Effect of Target Position and Tactual Recognition Field Size on Touch Bias BIBAFull-Text 769-772
  Elizabeth L. Wilson; Shawn M. Doherty
Past studies have shown that touchscreen display angles other than those that perpendicularly bisect the operator's line of sight cause the operator to touch slightly below the target. The amount of bias created from this misjudgment fluctuates according to the target's position on the screen. Additionally, the percentage of touches that activate a specific target varies according to the size of the tactual recognition field. This study sought to match three square tactual recognition field sizes with the amount of touch bias occurring in each location. The results showed that although bias differed according to location, the tactual recognition fields did not vary enough in size, nor were they large enough to find a significant difference between them in the number of touches captured according to the location of the target. The tactual recognition field that optimally captures responses varies in size over display position and is non-square in shape.
Psychomotor Efficiency in Users of Notebook Input Devices: Confirmation and Restrictions of Fitts' Law as an Evaluative Tool for User-Friendly Design BIBAFull-Text 773-777
  Christine Sutter; Martina Ziefle
On the basis of Fitts' law the present study examined the psychomotor efficiency for 20 experienced users of force- (trackpoint) and motion-input (touchpad) devices in clicking and dragging tasks. Beyond task difficulty the impact of input modality, practice, and task type was investigated. On the one hand, the results support Fitts' law since performance data of both input devices fitted satisfyingly with Fitts' predictions. Motion-input was found to be very robust towards task difficulty, especially in dragging tasks. On the other hand, the results were incompatible to Fitts' assumptions as target size and distance did not equally contribute to task difficulty but rather target size was a stronger contributor. Thus, the effective task difficulty in small targets was notably underestimated. For user-friendly interfaces, button widths of over 0.5 cm should be provided, especially when distances farther than 7.5 cm are inevitable.
Comparison of Mobile Text Entry Methods BIBAFull-Text 778-782
  Melinda M. Cerney; Brian D. Mila; Lewis C. Hill
In this preliminary study, we tested a small group of users on their ability to perform common text input tasks using both standard and unfamiliar input devices: the standard QWERTY keyboard, an onscreen QWERTY keyboard on a Pocket PC, a letter recognition system on a Pocket PC, and a T9 text-input system on a cellular phone. We examined user performance, accuracy, and overall preference for the four input methods, and compared these results to the values predicted by Fitts' Law. Our findings suggest that the cognitive effort loads for each device had a strong impact on the amount of time required by users to input text, and that Fitts' Law methods do not accurately account for or predict values including cognitive load or skill transfer.
Selection Accuracy with Pen Selection Slots BIBAFull-Text 783-787
  James R. Lewis
This paper describes three selection accuracy experiments with the selection slot, a new menu selection device for pen-based computer systems. A selection slot is a slot into which a user places the tip of a pen or stylus for the purpose of selecting an item from a list of items. The results of the first experiment, using a prototype slot for notebook name selection with 3 mm per notebook name, indicated 100% selection accuracy. In a second experiment, the results indicated that with as little as 1.1 mm per notebook name, users could select notebook names with 100% accuracy. A third experiment evaluated page selection accuracy for 55- and 99-page slots using a 73 mm slot (0.74 mm per page for 99 pages). Participants in the 55-page condition used a single-page advance control to reach target pages greater than 55. Considering all targets, participants were slightly but consistently less accurate with the 99-page slots, but their within-slot selection accuracies were equal. All participants preferred the 99-page slot due to the inconvenience of acquiring pages greater than 55 with the single-page advance control.
Input Rates for a One-Handed Input Device (OHAI) for Chinese Text Entry BIBAFull-Text 788-792
  Michael D. Fleetwood; Chris S. Fick
As computer technology has become ubiquitous in nature, designers must develop text-entry methods that can accommodate a variety of devices, cultures, and languages. This paper presents a study evaluating a One-HAnded Input (OHAI) device developed for mobile text-entry in Chinese. The device is a chorded keyboard system on which text is entered in Chinese using the pinyin system. Participants trained with the device for 10, 1-hour sessions. Their text-entry rates and their rate of input for individual chords were measured after each session. The Power Law of Practice was used to predict input rates after 100 hours of training. Predicted input rates approximate 16 characters per minute, approaching pinyin input rates on conventional keyboards. Input rates for individual chords were also measured in order that future iterations of the software may associate the most commonly used characters with the fastest-to-execute chords. The study also suggests several potential future improvements to the OHAI system, such as augmenting the software with an autocompletion system.

COMPUTER SYSTEMS: Interfaces: Making Them Work

A Usability Evaluation of Concentric Rings in Relationship Graphing BIBAFull-Text 793-797
  Joseph H. Goldberg; Emily Liggett
A usability evaluation was conducted of a prototype radial graph visualization tool, to better understand whether concentric rings are useful for navigation and comprehension. Nodes represented sales representatives and contacts, and edges represented specific types of relationships. Double-clicking a graph node caused slow-in, slow-out, animated reorganization of the network about that node. Ten sales managers completed tasks ranging from graph comprehension to strategic analysis. Eye tracking was also utilized to address specific usability questions. Tasks were generally completed in 1-3 minutes, but assists revealed significant confusion with relationship concepts and terminology. Specific difficulties were related to filtering the graph and with occlusion of specific nodes. Eye tracking confirmed that concentric rings are used while searching nodes within the same level. Subjective assessments were quite positive, compared with presently-used enterprise sales network analysis tools.
Eye Movement and Reaction Time are Both Important in Assessment of Dialog Box Usability BIBAFull-Text 798-802
  Bruce N. Walker; Raymond M. Stanley
Traditional usability metrics (accuracy and reaction time) were combined with eye movement patterns to study button placement and highlighting in dialog boxes. Participants made button-click responses based on the contents of the dialog box text. Traditional measures and eye movement patterns yielded different results: Reaction time analyses suggested placing the correct button to the left; eye movement patterns suggested placing the correct button on the right. This study demonstrated that eye movements are a rich source of information for usability research, provided theoretical guidelines for future research, and showed the strengths and weaknesses of eye tracking in comparison to more traditional usability metrics. In addition, it provided empirical support for eye movement heuristics that are often implemented in visual interface design, showing that the search patterns for dialog boxes follow a reading pattern.
Keyboard Shortcut Usage: The Roles of Social Factors and Computer Experience BIBAFull-Text 803-807
  S. Camille Peres; Franklin P. Tamborello; Michael D. Fleetwood; Phillip Chung; Danielle L. Paige-Smith
Previous research (Lane, Napier, Peres, & Sandor, in press) has shown that despite the fact that it typically takes half as much time to issue a command to a computer application using that command's keyboard shortcut, most people issue a particular command by clicking an icon on a toolbar or by selecting the command from a pull-down menu. This study examined reasons why that might be the case with a web survey that focused on demographic characteristics of people who do and do not use keyboard shortcuts, as well as social factors of computer use that might influence use of keyboard shortcuts. Participants' shortcut usage was influenced by social factors, such as working in an environment with other shortcut users and experiential factors, primarily the hours spent using a computer per week.
User-Centered Symbol Design Through Human-Computer Collaboration BIBAFull-Text 808-812
  Brian Carnahan; Nathan T. Dorris
The purpose of this research was to develop a new approach to symbol development that used an interactive evolutionary computation (IEC) algorithm to expand end-user participation in the design process. IEC iteratively employs subjective assessment and parameter recombination to create a population of anthropomorphic symbols that "evolve" based on user input. Three design groups, comprised of both student and industrial subjects, used the IEC algorithm to develop 60 symbols for awkward posture, an risk factor for work-related musculoskeletal disorders. Factor analysis was used to reduce the nine design parameters (i.e., limb angles) to a three-factor structure. Analysis of variance revealed that student generated symbols differed significantly from those created by industrial participants in terms of two of the three factor scores. Actual or potential applications of this research include a new approach to creating symbols that encourages end-user input into their design.
The Effects of Semantic and Syntactic Instruction on User Performance and Satisfaction in Search User Interface Design BIBAFull-Text 813-817
  Jennifer Bandos; Marc L. Resnick
Search engines have the potential to assist users in a variety of information retrieval tasks. Unfortunately, field studies show that they consistently fail to meet the usability goals of effective and efficient performance. Two of the primary drawbacks are that users do not apply correct semantic logic and syntax in their queries. This study investigates the use of targeted search hints, a form of in-line help, to improve query construction. The results show that search hints can improve performance, but with interactions that designers must consider. Some hints increase the time required to construct queries. Compound hints can also lead to reduced performance. The implications of these findings are discussed.

COMPUTER SYSTEMS: Mouse Design and Use

Evaluation of Two Pen Mouse Designs BIBAFull-Text 818-822
  Chia-chen Chao; Alan Hedge
Two pen mouse designs were compared with a conventional mouse design in a laboratory experiment. Sixteen Ss (8 men; 8 women) used each of the mice to perform a series of tasks. Wrist posture was measured while holding each mouse. Results show the pen mice decreased ulnar deviation and wrist pronation, the latter being more reduced for women. However, wrist extension was lowest for the conventional mouse. No significant differences in task performance were found between the 3 designs that were tested. Ss reported that the conventional mouse was easier to use than the pen mice and just over half of the Ss preferred this design. A longer-term study is warranted.
Gain and Angle of Approach Effects on Cursor-Positioning Time with a Mouse in Consideration of Fitts' Law BIBAFull-Text 823-827
  Shelby Thompson; Jeremy Slocum; Michael Bohan
Over the past decade, indirect pointing with a mouse has become a fundamental part of the GUI environment. In that regard research has used Fitts' law to measure speed and accuracy of the human-motor system when using input devices. Other studies have found that angle of approach also affects performance. However, most such analyses have not considered control-display gain as a factor. The present study found that gain interacted with angle of approach, amplitude, and target size on movement time. Fitts' law remained an effective predictor of movement time across all conditions; however, less variance was accounted for in the higher control-display gain conditions. Based on these results, recommendations are given for GUI design.
Does a Haptic Mouse Help Older Adults Use the Web BIBAFull-Text 828-831
  Kalmi Maheshwari; Marguerite Bergel; Thomas S. Tullis
The goal of our study was to learn if providing older adults with tactile feedback would improve their performance on the Web. The study examined the effects on performance of older users completing tasks on a prototype website using both a normal mouse and a mouse that provides haptic, or tactile, feedback. A total of 18 participants with low and high web experience took part in this experiment. These participants varied in age from 55 to 77 years. There was no correlation between age and level of experience with the Web. Performance was measured using task duration and task success. Results indicate an improvement in performance for users with less Web experience using the haptic mouse.
Comparison of Child and Adult Anthropometry: Considerations for Input Device Design BIBAFull-Text 832-835
  J. M. Blackstone; P. W. Johnson
A systematic evaluation of child and adult anthropometry was carried out in order to determine anthropometric differences that may impact the design of computer input devices. Hand strength and the anthropometric measurements of shoulder breadth, hand length, hand breadth and finger width were compared among adults and 5, 10 and 14-year-old children. On average, children were 60% the size of adults at age 5 and 86% the size by age 14. The proportional size difference was relatively constant across the anthropometric measurements analyzed. At age 5, there was virtually no overlap in the size distribution between adults and children; by age 10, about 20% of the adult and child population were the same size, and by age 14, about 60% of the adult and child population were similar in size. When comparing hand strength, on average adults were five times stronger than 5-year-old children. The 5-fold strength difference and lack of overlap in the size distributions between young children and adults may have some bearing on the appropriateness of children using adult size devices when they start to use computers in schools.
Gui Objects with Impenetrable Borders: Is Instruction Necessary BIBAFull-Text 836-840
  Brian R. Johnson; Keith S. Jones
Placing menus against the edge of the screen reduces selection times because it creates an impenetrable border between the menu and the edge of the screen that the mouse cursor cannot penetrate (Walker, Smelcer, & Nilsen, 1991). The presence of the impenetrable border changes how users move the mouse, so that selection times quicken compared to menus with a penetrable border. However, it is not readily apparent whether or not GUI users could realize the advantages of impenetrable borders without instruction. The purpose of this experiment was to assess whether or not users would discover the benefits of impenetrable borders spontaneously. Results suggest that only 50% of participants who were unaware of the presence of the impenetrable border actually detected it. Additionally, with practice participants who were successful at detecting the impenetrable border selected the targets as quickly as participants who received full instruction concerning the benefits of impenetrable borders.

COMPUTER SYSTEMS: Navigation and Feedback

A comparison of Internet connection troubleshooting strategies by experts and novices BIBAFull-Text 841-845
  Masaru Miyamoto; Momoko Nakatani; Masahiro Watanabe; Shunichi Yonemura; Katsuhiko Ogawa
This paper compares the strategies used by experts and novices in troubleshooting complex systems. As an example, we consider the case of establishing an Internet connection. The complexity of modern systems, such as the Internet, makes troubleshooting a very difficult task. Because many users experiencing trouble turn to the call-center, traffic loads are always heavy. This loads cost the company dearly to maintain adequate user support quality. We need to incorporate effective approaches to tackling the problems into self-service systems. Moreover, such knowledge is useful for FAQ design and creating response methods for call-center agents that can well support the troubleshooting process. Both are expected to greatly reduce call-center loads. To elucidate effective troubleshooting techniques, we compare the troubleshooting strategies of novices to those of experts. As a result, we showed that given an initial goal constraint, the experts try to eliminate modules unambiguously and so find the fault while novices remain stuck with their first guess.
Advanced Technology Master Caution Panel (ATMCP): Tracking Task Status by Monitoring Information Technology (IT) Resources BIBAFull-Text 846-850
  Andrea L. Pacley; Megan E. Reichert
Computers are increasingly becoming a part of society's everyday life and can cause a wide variety of impacts when they fail. For example, during a military exercise, Expeditionary Force Experiment (EFX) 98, it was found that operators were losing hours of work and data because they were unaware that essential systems had failed. This illustrated the need for a system that provided system situation awareness (SA) to the operator that rapidly disseminated information and responded quickly to connectivity and system failures. To fulfill this need, we created the Advanced Technology Master Caution Panel (ATMCP); analogous to an aircraft master caution panel. This system offers a unique approach to providing system SA that allows the operators to workaround system failures by mapping information technology (IT) resources to crew tasks as a method of monitoring task status. ATMCP offers unlimited flexibility and can be applied to multiple domain areas.
Emergency Automated Response System (EARS) BIBAFull-Text 851-855
  Joshua Phillips; Sachin Kogekar; Julie A. Adams
This paper presents a comparison of two versions of an Emergency Automated Response System (EARS), a fully manual version and a partially automated version. User evaluations involving both versions of the system were conducted using a low workload task and a high workload task. The results indicate that the automation employed by the partially automated system decreased overall response time and perceived workload for both tasks, but accuracy decreased and response times increased from low workload to high workload with both versions.
Enhancing Roboflag Users' Situational Awareness BIBAFull-Text 856-860
  Sangeeta Shankar; Yi Jin; Julie A. Adams; Bobby Bodenheimer
The RoboFlag system was designed as a testbed to study distributed control of multiple vehicle teams with humans in the loop. This work analyzed the RoboFlag version 2.0 interface to identify existing issues with the users' Situational Awareness (SA). The existing interface for RoboFlag was modified to create two new interfaces. The first interface focused on improved Situation Awareness. A user evaluation was conducted to determine if the new interfaces improved the users' SA over the original interface. Twenty-four participants completed the evaluation. This paper reports the design of the task environment, the evaluation method, and the statistical analysis. The results indicate that both new interfaces provide improved SA over the RoboFlag version 2.0 interface.
Designing a User Interface for a PDA-Based Campus Navigation Device BIBAFull-Text 861-865
  Brian Dorn; Daniel Zelik; Harisudhakar Vepadharmalingam; Mayukh Ghosh; S. Keith Adams
University campuses, like many other public and private institutional settings, pose challenges to visitors and newcomers finding their way from place to place. In some cases, such campuses have grown to the size of a small town. Maps and tour guides have traditionally been the means used to assist visitors find their way; however, the recent development of high-power, low-cost mobile computing opens the door to portable electronic navigational aids. This paper focuses on user interface concerns in a personal digital assistant (PDA) based campus guide. Cognitive and visual display engineering principles are used to develop a preferred preliminary design. Subjective feedback and quantitative data on the user interface are gathered in a small pilot study. The appropriateness of the design and its implications for future work are also discussed.


Is Practice Necessary to Speed the Selection of Web Browser Controls That Have Impenetrable Borders BIBAFull-Text 866-870
  Brian R. Johnson; Keith S. Jones; J. Shawn Farris
Previous research demonstrated that interface elements could be selected faster when placed against the edge of the screen. Doing so creates an impenetrable border between the element and the edge of the screen that the mouse cursor cannot penetrate. This changes how users move the mouse, so that selection quickens. This study investigated the effect of practice on the acquisition of targets with and without impenetrable borders. Ten participants selected targets that varied in Target Type (with or without impenetrable borders), and Distance (.5, 3.5, 6.5, 9.5, and 12.5 cm) across five Practice Sessions. The results confirmed that targets with impenetrable borders were selected faster than targets without impenetrable borders and that participants demonstrated consistent reductions in selection time over sessions, regardless of the target type. In addition, excessive practice was not necessary to demonstrate target type differences; thus the advantage of having impenetrable borders seems to be relatively instantaneous.
Examining First-Time Usage of the CombiMouse BIBAFull-Text 871-874
  Jeremy Slocum; Shelby Thompson; Barbara Chaparro; Michael Bohan
The CombiMouse is a new input device for personal computers that combines the functionality of a keyboard and a mouse into one device. The CombiMouse consists of two units, much like a split-keyboard, in which the left hand unit (LHU) is a stationary device with keys that are typically used by the left hand, while the right hand unit (RHU) contains keys typically used by the right hand, but is mobile and serves as a mouse. Preliminary results of first-time usage indicate the device to be very promising. Performance was shown to be just as efficient as the traditional mouse and significantly more efficient than the track ball. Typing performance was not as fast as the traditional keyboard; however, the participants showed improvement with more usage of the device.
A Survey of Online Reading Habits of Internet Users BIBAFull-Text 875-879
  A. Dawn Shaikh; Barbara S. Chaparro
This study evaluated the reading habits of Internet users across five document types. Internet users completed an online survey indicating whether they were likely to read a document online or on paper using five possible choices. Document types evaluated included journal articles, news, newsletters, literature, and product information. Results revealed differences in the reading habits based on document type. Journal articles were reported to be primarily printed while documents such as online news, newsletters, and product reviews were reported to be read mainly online. Users tended not to use online sources for reading literature. Primary factors determining whether a document was printed or read online were size, importance, and intended purpose of document.
Keypads for the Elderly BIBAFull-Text 880-884
  D. Cleve Mortimer; A. William Evans; J. Christopher Brill; Bryan Clark; Kay M. Stanney
Age-related physical and sensory decrements can influence user requirements for consumer technologies. The present study investigated several factors related to keypad design, a common means of interfacing with a variety of consumer systems ranging from mobile phones to ATMs. Participants performed a series of data entry tasks using an experimental keypad and a standard keypad. Performance data and subjective ratings were collected. The results suggest that performance was generally better when using the experimental keypad versus a standard keypad. In addition, participants preferred using the experimental keypad to a standard keypad. The results suggest that further consideration of age-related sensory and performance decrements is necessary when designing keypad interfaces. Based on these data, a series of guidelines for keypad design were developed.
Usability and Database Design Dependencies in a Department of Defense Application BIBAFull-Text 885-888
  Beth L. Giurelli; Susan Katz
User interface issues as well as application development issues related to the interdependency between usability goals and database design goals are described in the context of an on-going project funded by a Department of Defense organization. Examples of usability and database dependencies in the areas of data access, data granularity and multiple data formats are explained, and the impact of these issues on the project is described. The importance of early user profile analysis and task analysis is emphasized within the context of application-specific database modeling and system architecture needs. A high level knowledge of database issues proved to be useful tools for the human factors engineer in making contributions to the usability-cost tradeoff, and in facilitating collaboration and team work. These concepts are described within the context of usability goals.
The Effect of Heterogeneous Displays, Awareness Tools and Audio-Chat Communication on Team Collaboration BIBAFull-Text 889-891
  Deepak M. Kesavan-Namboothiri; Shazeeye Kirmani; Ann M. Bisantz
Advances in technology and connectivity have led to the development of sophisticated portable devices incorporating functional versatility and reduced sizes. Such devices add another level of complexity in systems which are designed to support communication and collaborative work. This study researched potential problems that arise when map-reading tasks were assigned to teams of two using various modalities of communication coupled with different display sizes and interface tools. Ninety-six participants, 6 pairs in 8 conditions, performed the experiment. Results indicate that large-large screen participants were more accurate than large-small screen size and took less time than small-small screen size in the audio condition. Chat participants took longer than audio participants in the large-small screen condition. The highlighter was most frequently used in the large-large screen condition and the pointer was most frequently used in the large-small screen condition.
An Illustrative Example of Four HCI Design Approaches for Evaluating an Automated System Interface BIBAFull-Text 892-896
  Haydee M. Cuevas
Automation technology has been embedded into nearly every facet of today's society, from cellular phones and personal digital assistants to automated teller machines to highly advanced systems in aviation and industrial operations. Still, the fundamental element for the successful operation of these products and systems is a well designed interface between humans and technology. To address this issue, this paper seeks to highlight how Ebert's (1994) four approaches to HCI design (ethnographic/anthropomorphic, cognitive, predictive modeling, empirical) can be effectively integrated to develop better interfaces between humans and society's complex systems. First, a brief overview of these approaches will be presented, emphasizing how the outcomes of one approach can inform the implementation of the next approach. Then, a step-by-step analysis of a hypothetical task performed using an automated postal machine will serve to illustrate the process of applying these approaches to evaluating an automated system interface.
Cognitive Task Analysis of Data Mining Processes in Bioinformatics Research BIBAFull-Text 897-901
  Jiao Ma; Colin G. Drury
Health care processes generate vast amounts of data of potential value to improve health and health care services. Bio-medical data, such as genetic data, need to be properly stored in data warehouses and analyzed to benefit health care. From a multidisciplinary perspective, Bioinformatics addresses research, development and application of computational tools and approaches for analyzing and thus expanding the use of biological, medical, behavioral and health data. Data mining techniques are often used by bioinformatics researchers. In the current project, a bootstrapping-themed Cognitive Task Analysis was adopted to analyze the data mining processes used by several bioinformatics researchers at the University at Buffalo, SUNY. Two of the Applied Cognitive Task Analysis (ACTA) techniques, "Task Diagram Interview" and "Knowledge Audit Interview," were integrated with questionnaire surveys and field observations. This paper presents the ACTA portion of the cognitive task analysis, and shows that there was agreement on most of the cognitive elements required for data mining.

COMPUTER SYSTEMS: Systems and Usability

Efficiency Assessment of an E-Commerce Data Management Tool Using Learning Curves BIBAFull-Text 902-906
  Diego Rivera
Learning curves for e-commerce data management tasks were computed to assess UI efficiency. Participants were asked to update product information using an e-commerce data management tool. Mean time on task over 20 trials of the same task was fit using a power function. Learning curves of 92.7% to 97.6% were found for two product update tasks. The results obtained indicate that making efficiency judgments based on the first few trials will produce higher learning coefficients that actually exist, and suggest that practitioners should not assume that time on task will always decrease significantly with increased practice. It also shows how properties of learning curves can help in the analysis of UI efficiency.
Understanding the Usability Construct: User-Perceived Usability BIBAFull-Text 907-911
  Mick McGee; Aaron Rich; Joe Dumas
The usability profession has seen success in industry and academia, as well as recognition in the popular press. However, inconsistent measurement, unreliable problem identification, inappropriate high-level goals, and a lack of valid metrics highlight recent usability literature. Rather than support or refute these findings, we offer a research introspection that we hope contributes to all of these issues by improving our basic understanding of the construct of usability. A Usability Concept Survey (UCS) containing 64 potential usability characteristics was created and administered to 46 users who rated how integral each characteristic was to usability. Multivariate analyses of these user perceptions were used to construct: 1) a taxonomy of usability to classify usability characteristics, 2) data-driven general dimensions of usability, 3) a map of usability space showing specific usability characteristics within the general dimensions; and, 4) a definition of usability. We believe this better understanding of the construct of usability can contribute directly to improving usability objectives, measures, and practice.
Expected Usability Magnitude Estimation BIBAFull-Text 912-916
  Aaron Rich; Mick McGee
Usability measures typically focus on actual user experiences while largely ignoring the impact of user expectations. User expectations provide insight into overall usability, user satisfaction, and priority of usability problems. Beyond test results, communicating user expectations can offset the negative connotation many development teams have of usability by showing examples where expectations are exceeded. This paper describes the expected Usability Magnitude Estimation (UME) method to assess user expectations in usability tests. The method is more valid, robust, and theoretically based than existing methods. It allows measurement of expectations that is easy to administer, simple to analyze, and provides actual and expected usability ratings along the same ratio scale of usability. Expectation data is used to classify tasks into empirically derived design strategy groupings based on refined theory. Overall, the method positively contributes to usability results and development team relationships.
A Persona-Centric Approach to Developing Complex Computer Systems: Lessons from the Field BIBAFull-Text 917-921
  Melroy E. D'Souza; Nancy H. Lincoln
Enterprise server systems, such as e-mail servers, database servers, and e-commerce servers, are the heart and soul of businesses throughout the world. They are complex back-end systems that typically fall under the realm of system administrators and developers, and drive many of the front-end client applications used by the billions of end-users in businesses on a regular basis. It is critical that these complex systems be easy to learn, install, use, troubleshoot, maintain, and upgrade. This paper describes our experience using a persona-based approach to develop complex e-business server systems. It provides an overview of personas and their benefits, the approach we took to create them and enable their adoption, and the lessons we learned that may be adapted by human factors professionals in different industries. The personas we created increased the product team's awareness of our target server audience, as well as their needs, skill levels and goals. The adoption of our personas has been fairly widespread, influencing everything from feature-based user-interface design decisions to far-reaching strategic planning for our next major product release.
A Cognitive Analysis of Equation Reading Applied to the Development of Assistive Technology for Visually-Impaired Students BIBAFull-Text 922-926
  Paula Barraza; Douglas J. Gillan; Arthur Karshmer; Skye Pazuchanics
The purpose of this research was to investigate the perceptual and cognitive processes involved in equation reading to apply that knowledge to the development of assistive technology for blind equation readers. The research used a process tracing observational study, three experiments, and an eye-tracking study to examine several hypotheses about equation reading: people (1) read equations from left to right, one element at a time, (2) back scan when reading equations, (3) substitute the outcome of a parenthetical expression for the initial elements, and (4) scan the entire equation before element by element reading to create a schematic structure. The process tracing study provided evidence for all of the hypotheses, with the experiments supporting the first three hypotheses, but not the fourth. These results have been implemented in assistive software for visually-impaired users, the Math Genie -- an auditory browser.

CONSUMER PRODUCTS: Issues in Usability

Why a Consumer Electronic Device is Difficult to Use BIBAFull-Text 927-931
  Melanie Diez
This paper describes a cognitive usability analysis of a home stereo as well as an experiment that tests the predictions borne out of that analysis using the RAFIV method of cognitive usability analysis (Sherry, Polson, Fennell, & Feary, 2002). At the heart of this method is a five-stage model that describes a user's cognitive steps as they perform a task. This model provides a framework for analyzing an interface by asking whether or not each stage can be accomplished purely through label-following. The results suggest that the RAFIV technique can be used to predict which tasks might prove difficult for users. Furthermore, it suggests that the number of recall steps within a task can play a negative role in a user's ability to complete that task.
Usability Problems in Consumer-Directed Broadcast Advertisements of Prescription Medicines BIBAFull-Text 932-936
  Carrie R. Slater; Tonya L. Smith-Jackson
The Federal Food, Drug, and Cosmetic Act broadly regulates the content of Consumer-Directed Broadcast Advertisements (CDBA). Information processing capabilities of average consumers may be exceeded by broadcast advertisements that present too much information. The purpose of this study was to examine usability problems encountered by viewers of broadcast advertisements and to isolate "best practices" that facilitated information transfer. Two age groups, older and younger viewers, evaluated different prescription drug advertisements based on usability and provided verbal reports to open-ended questions in a focus group. Avoiding information overload, eliminating or reducing distracting stimuli, and slowing the rate at which information is presented are important usability guidelines that should be applied to content specifications.
Strategies for Mainstream Cellular Phone Use by Individuals with Moderate to Severe Cognitive Impairments BIBAFull-Text 937-940
  G. C. Vanderheiden; R. K. Nelson; L. Yan; M. E. Sesto
A population often overlooked in the design of cellular phones is people with cognitive disabilities. This study evaluated the ability of persons with moderate to severe cognitive impairments to use mainstream cellular phones programmed with experimental interface features that allowed operation with minimum cognitive ability. Two modes were tested. The first allowed an individual to place calls by simply opening a flip phone. The second displayed four pictures on the touchscreen and allowed a call to be made by touching one of the pictures. Sixteen individuals with Mini-Mental State Examination (MMSE) scores from 6 to 19 participated. There was a 100% success rate using the flip mode in both Instruction and Carryover conditions and a 100% success rate in Instruction and 81.3% success in Carryover for the picture mode. This was compared to standard 'touchtone' dialing mode success rate of 12.5% in the Instruction condition and 6.3% in Carryover condition.
Creating Usable Wordless Instructions for Performing Complex One-Time Tasks: Effects of Violating the Rules BIBAFull-Text 941-945
  Michael A. Rodriguez; Peter G. Polson
We have developed design rules for diagrammatic instructions for initial setup, basic maintenance and troubleshooting (i.e., clearing paper jams) tasks. The study reported here evaluated these rules. Four groups of novice users cleared paper jams in a laser printer using one of four different diagrammatic instructions. Diagrams presented to the first two groups all followed the rules but differed in the number of actions per diagram (one verses 3-4). The remaining groups' instructions contained diagrams that violated one or more rules. Instructions that followed the diagram design rules resulted in no errors. Diagrams that prevented users from correctly identifying the location of a subtask resulted in the most severe errors. Other rule violations resulted in fewer errors of lesser severity so if users were shown the general location of the problem they could perform a subtask. Times to complete each subtask were similar unless the location rule was violated.
Effects of Screen Orientation and Margin on Reading with a Handheld Computer BIBAFull-Text 946-950
  Young S. Lee; Tonya L. Smith-Jackson
Although the small size of handheld computers increases portability and mobility, it causes difficulty reading information displayed on a small screen. In an attempt to improve text readability of handheld computers, this study investigated the effects of screen orientation and margin on reading speed, comprehension, and subjective ease of reading with a handheld computer. A 2x2 within-subject factorial design was conducted with 16 participants reading text from a PDA. In addition, users' preference for the two factors and their experiences with reading with the PDA were elicited in a post-experiment questionnaire. Finally, usability problems encountered were discussed in the interview. The results of this study indicated that neither screen orientation nor margin had a significant influence on reading performance. No prevailing preferences for screen orientation and margin were found. Invaluable qualitative information regarding usability problems was identified, which, in turn, supports several recommendations to improve reading from small screens of handheld computers.

CONSUMER PRODUCTS: Methods in Product Development and Evaluation

Development and Application of a Generation Method of Human Models for Ergonomic Product Design in Virtual Environment BIBAFull-Text 951-955
  Taebeum Ryu; In-Jun Jung; Heecheon You; Kwang-Jae Kim
A group of digital human models with various sizes which properly represents a population under consideration is needed in the design process of an ergonomic product in virtual environment. The present study proposes a two-step method which produces a representative group of human models in terms of stature and weight. The proposed method first generates a designated number of pairs of stature and weight within an accommodation range from the bivariate normal distribution of stature and weight of the target population. Then, from each pair of stature and weight, the method determines the sizes of body segments by using 'hierarchical' regression models and corresponding prediction distributions of individual values. The suggested method was applied to the 1988 US Army anthropometric survey data and implemented to a web-based system which generates a representative group of human models for the following parameters: nationality, gender, accommodation percentage, and number of human models.
One-Third Octave Band Spectral Characteristics and Consumers' Evaluation for Sound of Blouse Fabrics BIBAFull-Text 956-960
  Eunjou Yi; Jayoung Cho; Gilsoo Cho; John G. Casali; Gary S. Robinson
Ten woven fabrics for lady's blouse including natural silk and synthetic ones were selected and the objective sound characteristics including level pressure of total sound (LPToct), level range (ΔLoct), frequency difference (ΔLoct), and variance of levels (VLoct) were obtained from one-third octave band spectra of each rubbing sound of the fabrics. Consumers' subjective sensation (softness, loudness, sharpness, clearness, roughness, highness, and pleasantness) was rated by free modulus magnitude estimation (FMME). Silk and synthetic fabrics showed similar shapes of octave band spectra. Silk fabrics were found as sounding much more pleasant than synthetic ones. In relationship between objective measurements and subjective sensation, subjective clearness for silk fabrics was explained significantly by ΔLoct and VLoct, whereas subjective softness was significantly described by the parameters for synthetic ones.
Development of a hierarchical estimation method for anthropometric variables BIBAFull-Text 961-965
  Heecheon You; Taebeum Ryu
Most regression models of anthropometric variables use stature and/or weight as regressors; however, these 'flat' regression models result in large errors for anthropometric variables having low correlations with the regressors. For better accuracy in estimating anthropometric variables, this study proposed a method to estimate anthropometric variables in a hierarchical manner based on the geometric and statistical relationships among the variables. By applying the proposed approach to 60 anthropometric variables selected for the design of an occupant package layout in a passenger car, hierarchical estimation structures were constructed and then based on the estimation structures hierarchical regression models were developed with the 1988 US Army anthropometric survey data. The hierarchical regression models were compared with the corresponding flat regression models in terms of adjusted R2 and SE, resulting in on average a 55% increase in adjusted R2 and a 31% decrease in SE when compared to the corresponding flat models.
User-Centered Design of a Wall Clock BIBAFull-Text 966-970
  Kristi E. Schmidt; Ilkin Hossoy
An analytical approach to the user-centered design of a wall clock utilizing an engineering model, a cost model, and a marketing model is demonstrated. An engineering model is used to optimize the design with respect to material use and functionality. A cost model considers fixed and variable costs for the producer. The marketing model utilizes preference data collected from a discrete choice conjoint analysis survey and analyzed with the logit model to represent user preferences quantitatively in the form of demand curves. The survey explores tradeoffs among four product characteristics (face diameter, frame width, font style, and font size) and price. The engineering, cost, and marketing models are integrated and the design is optimized to maximize profit by considering tradeoffs among design requirements, cost, price, and product characteristics. Cluster analysis defines three market segments within the survey preference data and solutions are optimized for each of the three market segments.
Affective Evaluation of Vehicle Interior Craftsmanship: Systematic Checklists for TouchFeel Quality of Surface-Covering Material BIBAFull-Text 971-975
  Myung Hwan Yun; Heecheon You; Wooyeun Geum; Dongjoon Kong
Touch/feel quality of interior material is a critical element of customer's perception of overall product quality. Manufactures are increasingly interested in the affective evaluation as the perception of quality is heavily related to customer's feeling toward the product. Surface material quality is characterized by complex touch-feel sensations. In this study, 30 participants rated their affective reactions (how pleasant I feel) to surface materials of 30 different automobile interiors. Four categories of the material characteristics are used in the evaluation; crash pad plastic, steering wheel plastic, wood grain and metal grain. Consistent with previous research, it was found that both the visual quality and touch/feel quality influenced customer's perception of the material quality. Variables related to touch/feel quality is structured as 'an affective quality checklist' for automobile interiors to be used by a trim engineering team of an automobile manufacturer.


Safety Evaluation of Weightlifting Apparatus BIBAFull-Text 976-979
  R. Beyer; T. J. Ayres; J. A. Mandell; J. Giffard; M. Larkin
Adjustable stops are available on many weightlifting machines, and have the potential to prevent some injuries that occur during exercise. The safety benefit depends in large part on whether and how the stops are used. Unobtrusive observations at health clubs indicate that most patrons fail to use the adjustable stops. Advantages and disadvantages of several approaches to injury prevention are considered.
Designing an Adjustable Stool for Height Based on Human Design Technology BIBAFull-Text 980-984
  Toshiki Yamaoka; Susumu Kubota; Mutsuo Nishimura
This paper describes how to design an adjustable stool for height based on Human Design Technology (HDT). HDT is a Human-centered Design/product development method of visualizing user requirements, which are extracted by 3P (three-point) task analysis and other tools, via a database of seventy design items and a structured concept. Namely a structured concept is constructed based on user requirements and make them visualized using seventy design items. The seventy design items of HDT are classified into the eight large groups: 1) User interface design (twenty-nine design items), 2) UD (nine design items), 3) Kansei (sensitivity) design (nine design items), 4) Product liability design (six design items), 5) Ecological design (five design items), 6) Robust design (five design items), 7) Maintenance design (two design items), and 8) other (human-machine interface design) (five design items). An adjustable stool for height was designed based on HDT.
Evaluation of Mobile Based Consumer Products: Key Usability Factors and Evaluation Framework BIBAFull-Text 985-989
  Myung Hwan Yun; Yong-Gu Ji; Joohwan Lee; Young-june Choi
The importance of usability has been increasingly recognized due to the enlargement, convergence and complication of product functions. Usability is becoming a key factor in determining the success of a product, so that users can understand how to operate it and benefit from the functionality it offers. In this study, usability evaluation plan and procedures for mobile products are given, based on the usability evaluation framework of everyday products that is under debate currently in the Europe. Suggested framework can be used as a tool for enhancing the usability of mobile products from the initial product development stage to the product review stage.
How Knowledgeable are Salespeople about the Usability of Their Merchandise BIBAFull-Text 990-994
  C. Melody Carswell; Cindy Lio; Jennifer McNally
Salespeople (selling dryers, cell phones, recliners, or jewelry) in 25 stores were asked to recommend products they believed to be easy to use. They were also asked which products or features were most likely to be helpful to customers with specific physical, cognitive, or sensory limitations. There was little consensus across salespeople selling the same product. There were surprising omissions and some examples of incorrect claims. Further, salespeople largely ignored (or were unaware of) design features that enhance sensory and cognitive usability. The majority of claims dealt with product features that purportedly reduce physical strain.

CONSUMER PRODUCTS: Product Development and Annual PDTG Product Award

The Role of User Processing and Task Change on Task Performance BIBAFull-Text 995-998
  Lesley Strawderman; Richard Koubek
The purpose of this research is to minimize the negative effects and maximize the benefits of the introduction of new technology to consumers. This paper examines the effect of user processing and product change on the acceptance of product upgrades. User processing is defined as the type of cognitive processing a user employs to complete a task, and is identified as either controlled or automated. Three types of product changes are examined: omission (removing a task step), commission (adding a task step), and sequence (changing the order of task steps). Both the short term and long term effects of these changes on user performance are examined. The platform utilized was an inventory management computer program. Task completion time was collected from 31 subjects. The results indicate a difference in user performance based on processing type: subjects adapted to changes in the program more readily when using controlled processing as opposed to automated processing. Users have difficulty recovering from a task change when they are using automated processing. When they are using controlled processing, the change is more readily accepted. The variability of their performance was greater when using controlled processing. Task changes were most readily adapted to when the change was that of sequence. Changes of omission and commission caused a greater negative effect on the subjects' performance.
Decision Making in Mass Customization of Mobile Phones BIBAFull-Text 999-1003
  Martin G. Helander; Brenda Tan Li Peng
Mass customization aims at satisfying individual customers, who are given an opportunity to select among several design features and order a unique product. In this experiment four web sites were created where users could specify the design features of a mobile phone. Two web sites were designed to build a mobile phone from scratch: One used a rating agent of design features, and the other had no rating agent. The two other web sites used an existing phone as a basis for design -- one used a rating agent and the other had no rating agent. Forty test persons participated in an experiment to evaluate the web sites. Half of them were male and half of them female. The use of the rating agent produced more consistent and better design. The model for mass customization -- whether building from scratch or modifying an existing phone -- had no impact on the results. There were no differences in results between males and females.
Third Annual User-Centered Product Design Award BIBAFull-Text 1004-1005
  Dianne L. McMullin; Stan Caplan
The Product Design Technical Group (formerly the Consumer Product Technical Group) sponsored the third annual user-centered product design competition emphasizing product design and the methods used to specify and achieve the design. Emphasis was placed on innovative and user-centered approaches to Human Factors and Industrial Design.

EDUCATION: Education Tools

Guidelines for Constructing Graphs BIBAFull-Text 1006-1010
  M. Petkosek; William F. Moroney
Data can be presented either as an inscription (graphs, tables, and diagrams) or summarized in text. Recognizing when to use a graph, table, or text is a critical element of effective writing. This paper provides guidance for presenting data in papers, theses, and dissertations. It focuses primarily on graphs -- the most powerful form of inscription -- and describes advantages and disadvantages of various graphical formats. Factors related to the effective design of graphs such as: size of data sets, type of data, usability, and human perception are considered.
Rapid Prototyping with Microsoft Powerpoint: Page Linking and Animation BIBAFull-Text 1011-1015
  Timothy J. Silvers; Christopher M. Voorheis; Shilo H. Anders
Microsoft PowerPoint allows designers to create medium fidelity interface prototypes. This paper describes how PowerPoint can easily be used to create dynamic displays that are interactive and provide animation, when resources do not permit the purchase of computer-based prototyping software and the design requires more than a pencil-and-paper prototype. With PowerPoint, designers can create interactive displays by hyperlinking objects to connect multiple slides. Additionally, animations can be created by using the same principles that govern children's "flip books".
Washington State's Ergonomics Ideas Bank (EIB). Preventing Work-Related Musculoskeletal Disorders (WMSDs) is Feasible by Making Ergonomics Principles Available to Employers BIBAFull-Text 1016-1020
  Ernesto Carcamo; Sharon L. Drozdowsky; Paul Marsh; Brian Criss
The state funded workers' compensation insurance in Washington State receives more than 50,000 claims a year (40% of all claims) from work-related musculoskeletal disorders (WMSDs). The annual direct cost of those claims is 410 million, and with additional indirect costs, the economic losses total over 1 billion dollars. The hazards that cause WMSDs must be controlled and reduced in workplaces. Business and labor working together need to decide on the implementation of ergonomics principles to reduce hazardous exposures. A survey of Washington State employers revealed that their biggest difficulty in implementing ergonomics was finding solutions. This presentation describes the Washington State Ergonomics Ideas Bank (EIB), a web-based service that can be accessed by employers and employees to search for ideas to help reduce WMSD hazards. Preliminary data indicate that the Bank is being used and user feedback is positive. It continues to grow as the public deposits ideas.
Using the PDA as an Educational Tool to Collect Work Measurement Data BIBAFull-Text 1021-1024
  Andris Freivalds; Shihyun Park; Dongjoon Kong
As human factors (HF) educators, we often struggle to find good, inexpensive tools that allow us to demonstrate both basic principles and practical applications. The following computer software, available on Palm Zires, allows students to collect work sampling data (with QuikSamp) and conduct time studies (with QuikTS) on the least expensive PDAs available, so that multiple units can be purchased at relatively low cost. In addition to the data collection capabilities, the students can also examine the tradeoffs between sample size and the accuracy of the study and other basic work measurement principles.
The Mental Rotation Tutors: A Flexible, Computer-Based Tutoring Model for Intelligent Problem Selection BIBAFull-Text 1025-1029
  Matthew R. E. Romoser; Beverly P. Woolf; Dan Bergeron; Donald L. Fisher
The present research focuses on the development of an intelligent, computer-based tutoring model for selecting problems in domains where multiple skills are needed to solve a problem and the reasons for errors are not easily diagnosed. In this paper we report on the development and evaluation of the Mental Rotation Tutors and the intelligent models driving the problem selection engine or "domain reasoner". The domain reasoner evaluated each student based upon seven different core skills and chose the next problem based upon the student's level of proficiency in all seven areas. Two versions of the tutor were developed. The first versions targeted improving the student's ability to infer what combination of rotations were required to go from one view to another. The second version targeted improving the student's ability to apply a provided set of rotations to an object and report the final orientation. The results of two successive experiments demonstrated that students with low spatial ability derived the most measurable benefit from interacting with the tutors. The tutors also successfully diagnosed students' skill levels and provided problems that were appropriate to each student's current level of proficiency.

EDUCATION: How Do You Teach HF to Colleagues at Work?

Teaching Human Factors and Ergonomics to Our Coworkers: Are We Extending Our Reach or Giving Away the Recipe for Our Secret Sauce BIBAFull-Text 1030-1034
  Sanjay Batra; Melinda Baker; Gavin Lew; Brian Peacock; Julia Rogers; Kerith Stender
Our profession has reached out to a wide audience with articles, books, and workshops about Human-Centered Design (HCD), Usability, and Ergonomics. Should we be teaching aspects of Human Factors and Ergonomics (HFE) to lay audiences? Education can help us in getting our ideas accepted, improve how team members work with us, and extend the reach of HFE. Is there value in teaching HFE methods, principles, and guidelines? Will laypersons be able to actually start applying HFE principles and guidelines without learning the underlying theory? Will they have the experience and pragmatics to properly apply guidelines? When we simplify our knowledge and skills to teach them to others, do we run the risk of trivializing our profession?


Academic Skills of Engineering Psychology Majors: A Comparative Study BIBAFull-Text 1035-1039
  Michael D. Matthews
Shattuck (2001) described the Engineering Psychology program at West Point and how its graduates are prepared to work in interdisciplinary design teams. The current research assessed the academic skills of senior Engineering Psychology cadets in ten basic areas, and compared them with similar measures taken among freshmen and senior leadership and management majors at the academy. Results indicated significant differences among the groups in seven areas including information gathering, groups/organizations, interpersonal, behavior management, critical thinking, research methods, and ethics/values. In general, seniors reported more developed skills than freshmen, and Engineering Psychology majors reported more research-related skills than Leadership and Management majors. Implications for program evaluation and development are discussed.
Designing an Educational Curriculum for Future Human Factors Professionals BIBAFull-Text 1040-1043
  Dahai Liu; Dennis Vincenzi; Frances Greene
Human Factors and Systems Department at Embry-Riddle Aeronautical University (ERAU) focuses on both traditional and emerging areas of Human Factors and Systems in Aviation and Aerospace. The majority of students will pursue a career in aviation after s/he graduates. So it is crucial to provide the proper curriculum for those students at the very beginning, in order to equip them with sufficient knowledge and skills. The ERAU model of Human Factors education starts with the analysis of the student needs and integrates relevant disciplines into a single program. Courses are designed to expose students to the general human factors theory, as well as the technical applications in aviation/aerospace. The transition between semesters follows a continuous and systematic pattern and a complete knowledge network will be built after four years in the program. This paper illustrated the structure of ERAU's model and uses four Human Factors courses as a case study.
An Industrial Engineering Curriculum Renewal Process for the Enhancement of Industrial Engineering Degree Programs BIBAFull-Text 1044-1048
  Jacob B. Mullenix; Saravanan Regunath; Raja J. Jacob; Anand K. Gramopadhye; Michael S. Leonard; Mary E. Kurz; Delbert L. Kimbler
The current Industrial Engineering curriculum implemented at most educational institutions in the United States is driven by curriculum reform included in the Roy Report which took place almost 40 years ago. It is clear that if Industrial Engineers are to keep pace with the changing environment we need to address the future of Industrial Engineering curriculum. In response, this paper outlines the development of a new scalable and deployable Industrial Engineering baccalaureate-degree curriculum renewal process. This model will be designed to permit scaling up from an information technology course kernel to a fully integrated Industrial Engineering undergraduate curriculum.
Using Guided Learner-Generated Instructional Strategies to Transform Learning into a Constructive Cognitive and Metacognitive Activity BIBAFull-Text 1049-1053
  Haydee M. Cuevas; Stephen M. Fiore; Clint A. Bowers; Eduardo Salas
Successful learning outcomes in learner-controlled, computer-based training environments are inherently dependent upon learners' possession of well-developed metacognitive skills, that is, how well learners are able to accurately monitor and regulate their knowledge acquisition process. The present study explored the effectiveness of embedding a guided learner-generated instructional strategy (query method), designed to support learners' cognitive and metacognitive processes, within the context of computer-based complex task training. In terms of cognitive processes, results showed that incorporating the query method into the training resulted in improved integration and application of task-relevant knowledge, as indicated by greater similarity to an expert model of the domain and better performance on an integrative transfer task. With regard to metacognitive processes, the query method may have also assisted participants in more accurately monitoring their comprehension, as indicated by their significantly lower bias scores. Results are discussed in the context of designing adaptive learning systems.

EDUCATION: Potpourri

Assessing and Improving User Satisfaction in Higher Education: A Role for Human Factors BIBAFull-Text 1054-1058
  William S. Helton; Jessica M. Neu; Tangy A. Shell; Alison J. Ramsey; Danielle M. Myers
The success of a human factors perspective in improving customer satisfaction in other industries is suggestive of application to higher education, which is increasingly regarded as an industry. An initial step in a human factors approach to higher education is to furnish a reliable measure of undergraduate customer satisfaction. The present study outlines two studies exploring the Cynical Attitudes Toward College Scale (CATCS; Brockway et al., 2002) as a measure of higher education customer satisfaction. The first study demonstrates the usefulness of the CATCS as a measure of costumer satisfaction by demonstrating differences between two user groups, traditional and nontraditional students. The second study demonstrates its relationship to an environmental design variable, personalization of living space in college dormitories. The CATCS may prove useful in investigating and improving the design of higher education.
Static versus Dynamic Presentation of Procedural Instruction: Investigating the Efficacy of Video-based Delivery BIBAFull-Text 1059-1063
  Lee Carroll; Eric N. Wiebe
In this study, a comparison of static (illustration and text annotation) and dynamic (video with audio annotation) delivery of procedural instructions on a highly spatial task is made. Two groups completed three origami paper-folding tasks, after which they answered a preferences questionnaire and then were asked to re-do the first origami task from memory. The results indicated a general advantage for the dynamic modality in both time for task completion and accuracy. However, complexity of the third origami task and video resolution mitigated the effectiveness of the dynamic modality. No significant difference was seen in instructional modality preference or in memory retention for the task.
The Cognitive and Affective Consequences of Non-Linear Forms of Information Acquisition BIBAFull-Text 1064-1068
  Craig M. Harvey; Robert C. Mathews; H. Denis Wu; Andrea Houston; Sean M. Lane; Robert Hines; Larry Nabatilan; Comeaux Kathern
Interruptions are a part of everyday life whether in the office, on the Internet, or via the phone. As a result, people are faced with diverting their attention, dealing with the interruption and then refocusing on the task that was interrupted. The goal of this research is to begin to systematically study the cognitive and affective consequences of non-linear forms of information acquisition compared to standard linear forms. Toward this goal we have begun to (1) explore the effect of user control on performance while navigating an information path via web-based information and distributed learning; and, (2) examine the utility of non-linear forms of "instruction" for increasing the ability of people to transfer their learning to new situations.
User Expectations and Perceptions of E-Learning Courses: Which Course Components Facilitate E-Learning Satisfaction BIBAFull-Text 1069-1073
  Anna L. Langhorne; Sarah J. Swierenga
A research study investigating user expectations, achievement, and satisfaction regarding twenty-five e-course components was conducted with 50 participants from 21 e-courses offered during the 2003 summer term at The University of Dayton. Qualitative and quantitative assessments were used to derive perceptions and rankings of course components relevant to facilitating learning, enhancing communication, and facilitating engagement in the e-courses. It may be concluded that a core set of course elements exists, which enables successful achievement and overall satisfaction for online learners.
A PC Based Model for Prediction of Visibility and Legibility for a Human Factors Engineer's Tool Box BIBAFull-Text 1074-1076
  Vivek D. Bhise; Rashad W. Hammoudeh
Target detection and legibility prediction problems are generally considered complex as they require a good understanding of knowledge in photometry, geometry, human visual functions and visual performance measurement. Therefore, only simple geometric or photometric models are generally provided in human factors text books in the forms such as equations, graphs, or nomograms. This paper presents an easy to use but a more comprehensive model developed for a human factors engineering class to understand the variables, photometric measurements and use of human visual threshold data. The model can be easily down-loaded and exercised by a PC user to quickly estimate visibility and legibility in a number of situations. The model serves as a great tool to analyze a number of "what if" scenarios and learn the basics of human visual performance. The model will be an excellent candidate for including in a practicing human factors engineer's tool box.

EDUCATION: Team Behavior -- Its Use for Human Factors Professionals

Teaching Team Behavior to Human Factors/Ergonomics Students BIBAFull-Text 1077-1080
  William F. Moroney; Nancy J. Stone; Barrett S. Caldwell; Colin G. Drury; Eduardo Salas
Most Human Factors/Ergonomics personnel participate as team members as part of their employment. To prepare them for this, graduate programs need to provide students with one or more team building experiences while they are in Graduate School. The purpose of this panel is to lay the groundwork for a "best practices" document so educators can take advantage of what others have tried. Hopefully the exchange of information at the 2004 meeting will lead to a "Guidelines" document that can be circulated among interested members of the Educators Professional Group and discuss at the 2005 meeting. The guidelines should describe what works, what doesn't, and perhaps provide some insight as to why.

ENVIRONMENTAL DESIGN: Environmental Design at the Office

Hand Use Preferences in Delimiting the Boundaries of Normal Working Area BIBAFull-Text 1081-1085
  Hyeg Joo Choi; Leonard S. Mark; Marvin J. Dainoff; Christopher Thompson; Sara Stasik; Brenna Veale
Geometric models of normal working area have been derived from analyses of theoretically possible, but contrived and restrictive arm and hand movements (Farley, 1955; Squire, 1959; Wang et al., 1999). It is unclear whether the resulting boundaries delimit a safe, comfortable and effective reach area. The goal of the current investigation was to obtain data that can establish reach boundaries that reflect actions that are both comfortable and efficient. Adults reached for objects placed in various directions and distances in front of them. The type of reach action used to pick up the object was categorized in an effort to demarcate reach envelopes for different reach actions and identify the directional location in the workspace at which people change from reaching with their right hand to using their left hand. These data showed that people's reach actions violated important characteristics of the geometric models, including the spatial symmetry in the use of the right and left hands. From these data we are able to construct "performance-based" models of workspace area.
Sitter-Selected Postures in an Office Chair with Minimal Task Constraints BIBAFull-Text 1086-1090
  Gretchen M. Gscheidle; Herman Miller; Matthew P. Reed
Studies of office workers' postures indicate that reclined postures are less common than upright or forward-leaning postures. Laboratory studies have shown that back extensor activity and internal pressure in the lumbar intervertebral disks are lower in reclined postures. Given these advantages, why don't workers recline more often? Postural constraints imposed by their work, particularly vision and hand-reach requirements, may preclude more upright postures. In a study at a large office facility, side-view photographs were used to measure the postures that 80 men and women chose when sitting in an office chair without a work task. All sitters chose substantially reclined postures, with backrest angles averaging 25 degrees from vertical. The findings provide evidence that office work should be designed such that workers can sit more frequently with the reclined torso postures that they would choose if they were not working.
Effects of an Electronic Height-Adjustable Worksurface on Computer Worker Musculoskeletal Discomfort and Productivity BIBAFull-Text 1091-1095
  Alan Hedge; Earnest J. Ray
Thirty three computer workers from two companies worked at fixed-height worksurfaces (FHWs) and then at electronic height-adjustable worksurfaces (EHAWs) for 4-6 weeks. Subjects completed survey questionnaires before and after using the EHAWs. Results showed significant decreases in the severity of musculoskeletal discomfort for most upper body segments. In the EHAW condition daily discomfort ratings were lower in the afternoon and productivity ratings improved. There was a strong preference for using the EHAWs. An attempt to assess any placebo effect met with limited success. Further studies are needed.
Office Workplace Change and Training Intervention: Effects on work Related Musculoskeletal Disorders and Environmental Satisfaction BIBAFull-Text 1096-1100
  Michelle M. Robertson
The effects of an office ergonomics workplace and training intervention on workers' knowledge and self-reported musculoskeletal discomfort and environmental satisfaction were investigated. An instructional systems design process was used to develop and evaluate an office ergonomics training program. It was hypothesized that the training and workplace intervention would allow the worker to more effectively use their workplace through increased office ergonomics knowledge and skills. Following the intervention, there was a significant increase in workers' office ergonomics knowledge and awareness. Self-reported work-related musculoskeletal disorders significantly decreased for the group who had a workplace change and received ergonomic training relative to a workplace change-only group and a no intervention control group. Environmental satisfaction increased for both the workplace change and training groups as compared to the control group.
Sources of Variance in Employee Perceptions of Occupancy Quality BIBAFull-Text 1101-1105
  Thomas J. Smith; Steve Orfield; Michael Role
This study addresses the goal of an integrative approach to evaluating the effects on work of environmental design. Results are based on pre-occupancy evaluations of 2 different office workplaces, with many parallels in occupancy design. Methods entailed: (1) measurement of noise, lighting, and thermal conditions at selected work stations; and (2) administration of an occupancy quality perceptual response survey questionnaire. A 2-step, least-squares (2SLS) multiple regression method was used for sources of variance analysis of responses to occupancy quality items on the questionnaire. The major result is that observed variance in major indicators of occupancy quality is not explained by responses to the same questionnaire items for the 2 sites. The findings support the conclusion that, across different occupancy design settings, observed variability in work behavior is not likely attributable to a universal set of design factors.


Perceptions and Performance as Indicators of Universal Design's Claimed Benefits BIBAFull-Text 1106-1110
  Gary Scott Danford
This field research project examined the claim that universally designed environments are significantly more usable by all consumers than equivalent non-universally designed environments. To test that claim, the project developed and tested two universal design outcome measures that examined subjective and objective indicators of environments' usability. These measures were then applied in case studies of buildings currently in use that varied in their design features' acknowledgment of the seven Principles of Universal Design.


Application of Universal Design Principles in the Design of a Self-Checkout System BIBAFull-Text 1111-1115
  Komal Bajaj; Gary A. Mirka; Carolyn M. Sommerich; Haig Khachatoorian
A study was conducted to explore the use of universal design principles in the redesign of a grocery store self-checkout system -- focusing on the accessibility for wheelchair users. Two checkout stations were built: one was a dimensionally accurate model of an existing system and the other was a redesign of this system, using universal design principles. Five wheelchair users and ten non-wheelchair users performed simulated self-checkout activities, using both checkout stations. The dependent variables were productivity, shoulder and torso posture, and users' subjective assessment. Results indicated that productivity was not significantly affected by checkout station type and posture was significantly improved -- peak shoulder angle was reduced by 64% in wheelchair users and by 69% in the non-wheelchair group, and peak sagittal angle (forward lean) of the torso was reduced by 66.5% for wheelchair-users. Subjective feedback from both user groups showed a preference for the redesigned checkout station.
Universal Design Performance Measures for Products to Support the Practice of Universal Design BIBAFull-Text 1116-1120
  Molly Follette Story; James L. Mueller
The development of a set of Universal Design Performance Measures based on the Principles of Universal Design is presented. The performance measures can be used to evaluate existing designs, guide the design process, and educate consumers and design students. The Universal Design Performance Measures for Products were developed to help optimize and measure the usability of product designs for populations that are diverse in age and ability. Five distinct versions of the Universal Design Performance Measures were drafted and reviewed by consumers with disabilities, professional product designers, and marketing managers. These were distilled into two working versions of the performance measures, one for consumers and one for designers. The Universal Design Performance Measures for Products were then tested with consumer households and professional product designers and their households across the United States. Considerations for using the performance measures are discussed.
Space Requirements for Wheeled Mobility Devices BIBAFull-Text 1121-1125
  Edward Steinfeld; Victor Paquet; David Feathers
Research on the size of wheeled mobility devices in the UK and Canada suggests that the dimensions for "clear floor area" of wheeled mobility devices as specified in U.S. standards are too small. Anthropometric research was conducted to verify that findings in other countries are relevant for the U.S. Findings support increasing the clear floor area dimensions. To provide universal access to buildings, it is necessary to exceed the current requirements of minimum standards until they are revised to reflect the increased size of wheeled mobility devices.
Human Factors in Public Facilities Design BIBAFull-Text 1126-1128
  Christina C. Mendat; Shanna J. Ward; Michael S. Wogalter
This article describes research examining people's perception of public facilities to show how consumers' beliefs can be used for environmental design and maintenance. In this study, beliefs about the negative aspects of public restroom environments were investigated. A total of 199 participants rated the level of various elements relevant to safety, design, and security. Cleanliness, better ventilation, and better maintenance were perceived as the greatest problems of public restroom designs. In general, females gave higher ratings. Many of the problem factors can be addressed using HF/E expertise.

FORENSICS PROFESSIONAL: A Two-Way Street -- With Hazards: Expert/Attorney Communications

A Two-Way Street With Hazards Expert/Attorney Communications BIBAFull-Text 1129-1130
  Richard J. Hornick; Alison G. Vredenburgh
This panel of attorneys and human factors experts will explore the wide array of communications issues relevant to the relationship between human factors experts and their client attorneys.


Individual Differences Related to Shooting Performance, in a Police Night-Training Shooting Exercise BIBAFull-Text 1131-1135
  S. C. Stafford; T. Oron-Gilad; J. L. Szalma; P. A. Hancock
Increased understanding of the stress and performance effects of gun range drills with police officers is of importance for law enforcement trainers. Seventy-one police officers participated in routine night shooting drills over a two week period as part of regular training regimen. This paper examines the effects of two shooting range tasks on police officer's time perception, individual differences, and shooting performance. Theoretical considerations led to the hypothesis that performance changes under stress may be related to distortions in the perception of time. However, the results of this study do not provide strong evidence for nomothetic effects of time distortion. Rather, it is more likely a function of individual differences. Future studies will examine potential individual differences variables that influence the relation between time distortion under stress and task performance.
Judgements of Risk Associated with Riding with a Reclined Seat in an Automobile BIBAFull-Text 1136-1139
  Timothy P. Rhoades; Elaine C. Wisniewski
This study assesses judgments of automobile passengers regarding risk associated with reclined seats. One hundred subjects exiting from state license renewal offices were first shown three photographs of a male sitting inside an automobile with the seat back positioned at different angles and asked to rank order the photographs from "most safe" to "least safe" and explain their ranking. Subjects were then presented with two photographs (upright and fully reclined) and asked which position had a reduced risk of serious injury to the abdomen or neck that could be caused by sliding under the safety belts in a frontal collision. In both the ranking and the forced-choice tasks, all but one of the subjects reported it is safer to have the seat back in a more upright position than in a fully-reclined position. Subjects in this study clearly recognized that sitting upright is safer than sitting fully reclined.
Defendant Wealth and Civil Litigation: The Effects of Profit Levels on Compensatory and Punitive Damages BIBAFull-Text 1140-1144
  Danielle L. Paige-Smith; Kenneth R. Laughery; Richard N. Bean
An experiment was conducted in order to examine the effects of defendant wealth on civil litigation damage award decisions. Wealth was manipulated in the form of company profits. This study combined two moderate profit values with the two extremes used in past research (Paige, et al 2003). All participants read three trial scenarios in which the Defendant Manufacturer was found responsible for the plaintiff's injuries and awarded either economic, punitive, or pain and suffering damages. Interestingly, with the inclusion of more moderate values, profit information was found to significantly influence punitive, pain and suffering, as well as economic damage awards. The pain and suffering relationship was not found in the previous study.

FORENSICS PROFESSIONAL: The Forensics Human Factors Consultant

The Forensics Human Factors Consultant BIBAFull-Text 1145-1149
  Kenneth Nemire
Over 55 members of the Forensics Professional Group (FPG) completed a survey about their forensics human factors work. The survey included items about experience, degrees and certifications, areas of specialty, and rates, as well as aspects of forensics practice such as advertising and ethics. Part of the survey results provided information about issues that interest and concern FPG members, including continuing education, networking, speaker bureau, fee structures, managing a forensics business, advertising tips, update on trends in forensics human factors, impact of Daubert, professional liability insurance and professional ethics. This panel will summarize the results of the survey, present information about selected issues based upon the panelists' experience, and provide opportunities for members to discuss these issues.

GENERAL SESSION: Augmented Cognition

Augmented Cognition Overview: Improving Information Intake Under Stress BIBAFull-Text 1150-1154
  Colby Raley; Roy Stripling; Amy Kruse; Dylan Schmorrow; James Patrey
Military operators are often put into complex human-machine interactive environments shown to fail when stressful situations are encountered. To enhance warfighter readiness and operational capability, DARPA's efforts in Augmented Cognition are developing a new generation of technologies to enable computational systems to adapt to the human's cognitive state in real-time. These augmented systems will be endowed with non-invasive sensors that provide objective measures of the warfighter's neurophysiological responses to ongoing events. Based on these measures, as well as cognitive and contextual models of the user's intentions and objectives, these systems will invoke validated mitigation strategies to enable maximal performance from the user, and to help return them to an optimally functional state. This panel provided an overview of the key components of an Augmented Cognition system, how its development and validation will be carried out, and where these technologies could be implemented both in military settings and beyond.

GENERAL SESSION: Lessons Learned

Effective Practices in Deploying Mobile Computing Devices for Field Operations in Process Industries BIBAFull-Text 1155-1159
  John Hajdukiewicz; Dal Vernon Reising
The deployment of mobile devices in process industries promises greater efficiencies in operations and more effective uses of limited plant resources, compared with current practices. Yet, the adoption and use of these devices has been limited. This paper reports effective practices, applications, and lessons learned from deploying mobile devices for field operations in the refining and petrochemicals industries. Six petrochemical production facilities participated in the study. We interviewed various stakeholders at these facilities on their culture, business drivers, field operations, current use of mobile devices, infrastructure and platforms in place, current applications, and potential needs. Four general areas were identified as critical to the success of deployment: 1) Organizations, Policies and Processes, 2) Applications, 3) Infrastructure, Hardware and Software, and 4) Training.
Motivational Factors Underlying Implementation of Occupational Safety and Health Management Systems in Polish Industry BIBAFull-Text 1160-1164
  Daniel Podgorski
Effective implementation in Poland of occupational safety and health (OSH) legislation based on European Union (EU) directives requires a promotion of OSH management systems (OSH MS). To this end, a series of voluntary standards has been adopted, setting forth OSH MS specifications and guidelines. However, the number of enterprises implementing OSH MS has been increasing slowly, which calls for a national policy on OSH MS promotion. In order to provide input data for the development of this policy, a survey was conducted in a group of 40 enterprises with OSH MS. The survey was aimed at identification of motivational factors underlying OSH MS implementation decisions. The results indicate the required actions. The main ones include increasing workers' participation in OSH activities and increasing the role of the National Labour Inspectorate in OSH MS promotion.
Temporal Factors of Human Error in Spar-H Human Reliability Analysis Modeling BIBAFull-Text 1165-1169
  Ronald L. Boring; David I. Gertman; Julie L. Marble
This paper introduces recent efforts to quantify temporal factors contributing to human error. Although these efforts were specifically derived from nuclear power plant operations, they can be applied to a variety of human factors scenarios involving safety critical systems. In contrast to earlier approaches for human reliability analysis, the present approach using the SPAR-H method considers temporal factors in relation to a wide range of performance shaping factors. It is the authors' intention to classify temporal factors in a broad human performance context, ultimately describing a richer data footing for estimating human error probabilities.
Teaching and Learning Design: Commonalty and Diversity in Ergonomics, HCI and Architecture Design Education BIBAFull-Text 1170-1174
  Rich Halstead-Nussloch; William Carpenter
For four years we have been developing a design pedagogy that merges significant aspects of our disciplines (architecture and HCI). This has culminated in a joint design course where we bridged between design-build courses in architecture and user-interaction engineering. In this paper we cover lessons learned, based on our experience. Using the pedagogy developed for the Bauhaus, we have identified five goals for design education. Primary among these is education that combines designing artifacts with building them. We report commonalities and differences between our professions that have a significant impact on design education. Our work points to three recommendations for cross-disciplinary design education. Primary among them is to focus on design studios to keep within practical and manageable bounds.
Survey of Opinions and Judgments on Load Carrying among Soldiers Engaged in Combat BIBAFull-Text 1175-1178
  James B. Sampson; Julie T. Weismantel; Charles E. Dean; Frederick J. DuPont
A questionnaire survey of opinions and judgments about load carrying techniques was distributed to soldiers operating in Afghanistan in 2003. The soldiers completed the surveys between combat missions. One hundred fifty three questionnaires were fully completed. The questionnaire was designed to determine preferences and understanding of load carrying relative to requirements for executing combat tasks. Questions were derived from statements about the biomechanics and comfort of load carrying during military movement. Results show that awareness of effective load carriage techniques is a function of military experience. Knowledge about how to carry loads was not uniform throughout those surveyed. Significantly different responses were obtained for soldiers with less than 4 years experience as compared to soldiers with 4-7 years and to those with more than 7 years of military experience. Findings suggest there may be a need for special training in load carriage early in the career of infantrymen.

GENERAL SESSION: New Practices in Human Factors

Cost-Justifying Investments in Advanced Human-Machine Interface Technologies I: A Cost-Benefit Framework for the Process Industries BIBAFull-Text 1179-1183
  Greg A. Jamieson; Dal Vernon C. Reising
Advanced human-machine interfaces (HMIs), such as those developed under the ecological interface design framework, continue to show substantial advantages for supporting effective operator control (Vicente, 2002). However, prospective industry users of these technologies have expressed a need to make a quantitative economic case for designing and implementing advanced HMIs. To date, no comprehensive cost justification study has been published on advanced HMIs. The purpose of this paper is to report original work on a cost-benefit framework for advanced HMI's. We first present a brief summary of findings from a literature review of existing human factors cost justification studies and present a working list of metrics. We then describe a general cost-benefit framework derived from this list of metrics and discuss issues to be considered in applying this model in practice.
Using Kinematics to Assess Software Usability and Ergonomic Risk Factors BIBAFull-Text 1184-1188
  Linda Guarascio-Howard; Robert Gray
Over fifty percent of the workforce utilize the computer and suffer health problems that include musculoskeletal disorders and physical discomfort (Newburger, 1999 and Work Loss Data Institute, 2001). Professionals from disciplines of human factors and ergonomics address computer issues independently. Usability and user interface issues are identified in the software development stage focusing on the users ability to perceive and understand the designed functions. Ergonomic professionals are involved in usability after implementation and upon complaints and user injury. The focus of ergonomics is to evaluate extreme postures, resulting from design that cause stress to the body. By using motion analysis, usability studies are enriched by identifying extreme movements in completing system tasks. In this paper we will present a novel method that utilizes the kinematics of the user's hand and wrist movements to simultaneously evaluate physical strain and usability.
Human Performance Models for Response to Alarm Notifications in the Process Industries: An Industrial Case Study BIBAFull-Text 1189-1193
  Dal Vernon C. Reising; Joshua L. Downs; Danni Bayn
The Engineering Equipment and Materials User Association (EEMUA) recently published recommendations for average and peak alarm rates of 1 alarm per 10 minutes during normal operations and no more than 10 alarms per 10 minutes following an upset condition, respectively. However, these recommendations have been made in the absence of human performance studies or theory. This paper presents two studies -- an analytical Keystroke-Level Modeling study and a Markov modeling study -- that provide an initial human performance context for the EEMUA recommendations. Results suggest that these EEMUA recommendations are in line with human performance limits. Several limitations of the two studies for generalizing from either the KLM or Markov modeling results are discussed. Practical implications presented include the need for advanced alarm reduction techniques and consideration of peak alarm rates for upset conditions during the alarm rationalization process. Future research directions are also discussed, such as establishing the duration for which the EEMUA recommendation for peak alarm rates can be endured by a human operator.
Toward the Construction of an Efficient Set of Robot Arm Operator Performance Metrics BIBAFull-Text 1194-1198
  Tyler M. Akagi; Robert E. Schlegel; Randa L. Shehab; Kirby Gilliland; Tamy L. Fry; Quintin Hughes
As part of a larger project to identify and validate relevant quantitative measures of robot arm operator proficiency, fifteen metrics of arm maneuvering and hand controller performance were defined and measured for 3-DOF translational movement tasks. Twelve freshly trained operators provided performance data for seven target-acquisition task scenarios involving a variety of distance combinations along the X, Y, and Z axes. Metrics included indicators of task component times, distance traveled, inefficient (inverse) motion, maximum velocities, amount of multi-axis control, and input control onset times along the three axes. Pairwise correlations of all measures and scatter plots of variables yielding strong intercorrelations were examined to determine the potential underlying causes of the significant relationships. By identifying subsets of metrics with explainable co-dependencies, the overall metric set can be reduced to a limited number of key metrics that serve as effective discriminators of operator performance.


Reflective Clothing is Attractive to Pedestrians BIBAFull-Text 1199-1202
  Theresa M. Costello; Michael S. Wogalter
Motor vehicle crash fatalities involving pedestrians result in 1.8 deaths per 100,000 population annually in the US. Most of these fatalities are attributed to the pedestrian not being seen in time for the driver to avoid a collision, particularly under poor lighting conditions. Previous research shows that reflective clothing worn at night significantly increases a pedestrian's visual conspicuity to drivers, especially when worn on a part of the body that moves. The purpose of the present research was to examine pedestrians' willingness to pay an additional dollar amount for clothing providing increased conspicuity at night. Two studies were conducted with sample sizes of n = 340 and 325, respectively, comprised of university students and non-students. Findings from these two studies suggest that over 49 percent of respondents would be willing to pay an additional amount (33 versus 30) for a sweat shirt or jacket, and over 60 percent would pay the same additional amount for athletic shoes. These findings suggest that a relatively large segment of the population are interested in and would be willing to spend more for clothing with reflective material. In both studies, significantly more women than men selected the reflective material option. Respondents spending more time outdoors at dusk or at night walking, running or jogging professed a significantly greater willingness to purchase the reflective clothing than respondents reporting spending less time outdoors at dusk or after dark. Implications for product marketing and future research are discussed.

GENERAL SESSION: Virtual Reality Simulators in Medicine: Current and Future Concerns

Virtual Reality Simulators in Medicine: Current and Future Concerns BIBAFull-Text 1203-1207
  Mark W. Scerbo
There has been recent surge in the development of medical virtual reality simulators. These systems incorporate visual, auditory, and haptic displays and enable users to learn the skills needed to perform medical and surgical procedures in much the same way that flight simulators facilitate pilot training. These devices offer numerous training benefits to the user and also have the potential to improve patient safety. Despite these advantages, the medical community has been slow to embrace this technology. In fact, many of the current systems appear to showcase what can be done from a technological perspective instead of what should be done from the user's perspective. Thus, the purpose of this panel is to bring together experts who use, evaluate, and train with medical VR simulators to discuss current and future human factors concerns that impact the acceptance of this new technology.


Training and Individual Difference Effects on the Ability to Visually Discriminate Serially Presented Graphics: Short Term Memory Capacity in Analytic and Holistic Cognitive Styles BIBAFull-Text 1208-1212
  Elizabeth Kramer Pratt; James H. Pratt
Participants were screened for individual differences in short term memory (STM) capacity (high, low) and cognitive style (analytic, holistic) before beginning a serially-presented visual discrimination task. Participants were trained with either easy or difficult discriminations, then were transferred to novel discriminations. Variables were measured on a continuum, then dichotomized for analysis of variance. Cognitive style did not correlate with STM capacity. The two individual difference measures interacted, however, to affect accuracy performance on the transfer session of the discrimination task. Results suggest that individual differences in cognitive ability and cognitive style are orthogonal constructs that interact to affect skill acquisition and strategy development for visual-spatial tasks. Implications related to discrimination training and computer interface design are discussed.
A Study of Field Independence and United States Military Air Traffic Controllers BIBAFull-Text 1213-1217
  Helene A. Maliko-Abraham
Research was conducted using United States Air Force (USAF) and United States Navy (USN) Air Traffic Control Specialists (ATCSs). The Embedded Figures Test (EFT) was used to assess the existence of the underlying ability of field independence. This study investigated the hypothesis that active duty military ATCSs, as a group, tend to be more field independent than a comparable group of military personnel who were not controllers. This research effort showed that the underlying ability of field independence was possessed by the military ATCSs in the samples used.
Trait-Based Individual Differences on Discomfort Glare Rating Responses and Related Visual Contrast Sensitivity BIBAFull-Text 1218-1222
  Thurmon E. Lockhart; Haruetai Mekaroonreung
The objective of the study was to investigate the relationship between Trait-based Individual differences (neuroticism and extraversion) on glare subjective responses and contrast sensitivity performance when exposed to same manipulated glare conditions. An attempt was made to explore the relationship between the glare subjective responses and actual contrast sensitivity. Thirty-six individuals (9 high neuroticism scorers, 9 low neuroticism scorers, 9 high extraversion scorers, and 9 low extraversion scorers) were tested on subjective discomfort glare rating responses and visual contrast sensitivity. The International Personality Item Pool (IPIP) was used to assess trait-based individual differences, while the subjective glare experience was examined utilizing modified glare De Boer discomfort rating scale. The visual performance was measured through the contrast sensitivity level using adjustable contrast level of the Landolt's C target. Results indicated significant effect of extraversion trait on rating response while insignificant effect on visual related performance. The relationship between rating response and visual performance was also found to be quite minimal. In conclusion, the expected model was supported but only on the extraversion trait. Overall, the research was directed towards improving our understanding of influencing factors on the experience of discomfort glare, which may eventually have practical implications in the design of glare measurement methods, training and selection of drivers and workers who work under conditions of glare.
Worldview and Acculturation as Predictors of Performance: Addressing These Variables in Human Factors/Ergonomics Research BIBAFull-Text 1223-1227
  Mark E. Koltko-Rivera; H. C. Ganey; Joseph Dalton; Peter A. Hancock
Researchers in human factors and ergonomics (HF/E) are encouraged to consider two classes of predictor variables that typically are not included in traditional performance research: worldview and acculturation. Worldviews are sets of assumptions about life and the physical and social worlds. Acculturation involves the degree of commitment made to a culture's set of values and practices. Worldview and acculturation are highly relevant to performance. Two worldview variables, Individualism -- Collectivism and Locus of Control, have attracted research interest. At least four other dimensions within Koltko-Rivera's (2004) collated model of worldview are likely to be relevant to performance: mutability, time orientation, relation to authority, and interaction. As industrialized societies become more diverse, acculturation becomes more relevant to performance. Several areas are identified for future research, such as worldview/acculturation -- task interactions, and team cognition. Assessment instrumentation is briefly described.


Stress Vulnerability, Coping and Risk-Taking Behaviors During Simulated Driving BIBAFull-Text 1228-1232
  Amanda K. Emo; Gerald Matthews; Gregory Funke; Joel S. Warm
112 college students participated in a study of simulated driving. The aim of the study was to investigate how coping related to both subjective stress responses and objective indices of risk-taking behavior. Dispositional coping (i.e., typical coping style) predicted task-induced stress responses, including increased distress and loss of task engagement. Consistent with the transactional model of driver stress, the effect of dispositional coping was mediated by the situational strategies adopted in response to the specific situation. Task-focused coping appeared to be more adaptive than emotion-focused coping. Drivers were afforded opportunities to pass other traffic in risky circumstances. Dispositional coping factors, especially a confrontive coping dimension, predicted risk-taking behaviors, such as frequent passing. These effects were not mediated by situational coping, suggesting that emotions during driving may shape habitual behavioral styles that operate irrespective of current mood and coping strategy. Implications of the findings for countermeasures to driver stress are discussed.
The Impact of Dispositional Optimism and Pessimism on Stress as a Function of Psychophysical Task Characteristics BIBAFull-Text 1233-1237
  J. M. Ross; J. L. Szalma; P. A. Hancock
In this study we tested the effect of individual differences in dispositional optimism and pessimism on target detection. Following proximal task dimensions set out by the Model of Maximal Adaptability, three tasks were employed in the current study, varying in their spatial and temporal emphasis. Performance as measured by self report of stress was examined in light of individual differences in attentional narrowing across the three task levels. Prior research indicates that optimism predicts increased Task-Engagement, but in this study there was a novel finding that higher levels of optimism predicted decreased Task-Engagement in spatial-dominant tasks. Optimism was also found to predict increased levels of post-task Worry in temporal-dominant tasks. However, expected relations between pessimism as post-task stress state were not observed. Although the results of the current study did not confirm the hypotheses regarding joint resource capacities for spatial and temporal task components, results did indicate that dispositional optimism does impact Task-Engagement, signifying a need for further research on the relation between this trait and participant stress. The results extend prior findings that the relationship between these traits and stress states may depend on the psychophysical characteristics of the target detection task employed.
Validation of a Short Stress State Questionnaire BIBAFull-Text 1238-1242
  William S. Helton
Stress is an important aspect of operational settings. This article presents two studies providing initial psychometric and validation evidence of a short multidimensional self-report measure of stress state, the Short Stress State Questionnaire (SSSQ) based on the Dundee Stress State Questionnaire (DSSQ; Matthews et al., 1999, 2002). The first study involved the construction and exploration of the factor structure of the SSSQ using data pooled from three samples. These factor analyses differentiated three aspects of subjective stress similar to the DSSQ: Task Engagement, Distress, and Worry. The second study aimed at providing validity information on the SSSQ in regards to its sensitivity to task-stressors. Different task conditions elicited unique patterns of stress state on the three factors of the SSSQ in line with predictions. The 24-item SSSQ appears to be a useful measure of stress state based on the substantially longer DSSQ from which it was derived.
Sleep Patterns and the Impact on Performance: A Study of Men and Women Enrolled at the United States Military Academy BIBAFull-Text 1243-1247
  Nita Lewis Miller; Lawrence G. Shattuck; Jennifer K. Clark
Sleep requirements of adolescents and young adults are distinct from those of other age groups due to differences in the circadian rhythms of the sleep-controlling hormone, melatonin. This study examined the sleep patterns of cadets during their first year of training and study at the United States Military Academy (USMA). The study population included the entire USMA class of 2007 (n 1300) and a small group of upperclassmen (n=40). Actigraphy was recorded on a sample of the class (n=80). Survey results compared sleep patterns prior to reporting to USMA with sleep patterns during Cadet Basic Training and during the Fall semester, 2003. This baseline data collection effort sets the stage for follow-on interventions that will attempt to rectify inadequacies in the sleep patterns of cadets.


Mental Models of Computers as a Function of Sex and Perceived Trust BIBAFull-Text 1248-1251
  Valerie K. Sims; Matthew G. Chin; Lisa M. Durrance; Cheryl I. Johnson
Participants completed a measure of computer trust and generated responses to the question, "What is like a computer?" These responses were coded as one of seven types ranging from being perceptually similar to sharing similar functions to being cognitively similar. Computer trust scores were associated with generating more responses, particularly of a functional nature. However, further analyses showed that participant sex moderated this effect, with computer trust associated with functional analogies for males, but perceptual analogies for females. The results suggest that computer trust and mental models may develop together and should be considered as important variables in the design and training for future technology.
Measuring Individual Differences in Anthropomorphism Toward Machines and Animals BIBAFull-Text 1252-1255
  Matthew G. Chin; Valerie K. Sims; Bryan Clark; Gabriel Rivera Lopez
Two scales were constructed to assess anthropomorphism during human-machine and human-animal interactions. Participants were asked about their tendencies to self-engage in anthropomorphic behaviors and their attributions about others' anthropomorphic behaviors. Results indicated that the tendency to anthropomorphize pets is distinct from the tendency to anthropomorphize artifacts such as cars and computers. Parallel results were obtained for the attributions. Subsequent analyses showed a gender difference for the general tendency to self-engage in anthropomorphic behaviors and the nature of the attributions made for others' anthropomorphic behaviors. Females reported that they anthropomorphized animals more than males. They also made more positive attributions for others' anthropomorphic behaviors toward animals. No gender differences were observed for anthropomorphism toward artifacts. Overall, the results support a necessary distinction between anthropomorphism directed toward animals versus artifacts. They also suggest that gender differences in anthropomorphism need to be considered when designing "intelligent agents" that can interact effectively with humans.
Augmented Cognition: Developing and Testing a Physiology-Based Task Adaptation System BIBAFull-Text 1256-1260
  Stephanie R. Fishel; Justin M. Owens; Eric R. Muth; Adam W. Hoover; Jeromie R. Rand
The purpose of this study was to examine if an individual's performance could be improved by integrating physiological arousal data with a computer task, specifically a video game, which increased or decreased in difficulty based on the person's physiological status. Ninety-nine participants (80 males; 19 females) were included in the data analyses. The mean age of the included participants was 21.9 years (SD = 2.6). Using cardiac inter-beat interval (IBI) data each individual's respiratory sinus arrhythmia (RSA) was derived and used to objectively assess the parasympathetic activity of the autonomic nervous system. The RSA data were continuously converted into a standardized arousal score. In the condition of interest, Auto, the difficulty of the computer game was continuously manipulated based on the real-time arousal score of the participant. Subjective arousal data were also collected verbally throughout each experimental session. It was hypothesized that manipulating the difficulty of the computer game such that arousal was maintained at an optimal level would result in better performance compared to yoked and manual control of game difficulty. Results showed that automated task difficulty manipulation actually resulted in lower performance scores compared to yoked assistance manipulation, and tended to result in lower scores compared to manual assistance manipulation.
Field Independence and Spatial Ability in the Search for the Presence and Absence of Features BIBAFull-Text 1261-1265
  Elizabeth A. Schmidt; Marl W. Scerbo
The present study examined whether search times for the presence and absence of features are moderated by the ability to perceive parts of the visual field separate from their background (field dependence/independence) and spatial ability. Participants were administered the WAIS and the GEFT and divided into field dependent and independent groups. They then searched displays for targets with and without a specific feature. It was expected that field independent individuals would have faster search times for targets that lacked a feature because of more efficient serial processing mechanisms. Although there was a trend for faster response times to feature absent targets among field independent individuals, it was not significant. Instead, spatial ability was significantly correlated with feature absent search times. These findings suggest that the WAIS may be a useful selection instrument for jobs that require serial visual processing.
Bridging the Gap between Reduced Training Time and Maintained Operational Demands BIBAFull-Text 1266-1270
  N. G. Hans Jander; T. A. Jonathan Borgvall
As a consequence of decreased defense budgets, the training time of conscript combat boat 90 operators has recently been reduced. The effect has been an increased number of drop-outs, detachments, and accidents during the training. The need to improve this precarious situation is urgent. This encouraged a study with the purpose of measuring abilities identified as important for being successful in the training, and hence a high-performing and safe combat boat 90 operator. The objective was to improve the selection process in order to minimize drop-outs, detachments, and accidents during the training. The test battery consisted of psychometric tests measuring spatial and verbal working memory, problem solving ability, risk willingness, and social capacity. The results of the psychometric tests were compared with instructor ratings of performance during the training. The only test that showed to reliably predict a successful combat boat 90 operator was the test that measured verbal working memory.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Stress Effects on Soldier Performance

Stress Effects on Soldier Performance BIBAFull-Text 1271-1274
  C. Shawn Burke; Peter Hancock; Joel Warm; Jim Szalma; Tal Oron-Gilad; Wayne Harris; Client Bowers
The complexity of the modern battlefield requires that significant practice and training must be provided to ensure success in situations where failure is not an option. Performance within these environments occurs against a background of threat which ensures that acute and chronic forms of stress are a constant presence. However, there remain many questions to be answered regarding the impact of stress on soldier performance. The proposed panel is comprised of experts whom have generated work from disparate paradigmatic perspectives to study the issues related to stress and human performance within the laboratory as well as the field. The panel's goal is to present/discuss critical issues that confront those who wish to understand soldier performance under stress. Although we focus on the soldier, in principle, our work can apply to any individual who finds themselves faced with decision uncertainty in ambiguous situations in which flawed performance can have serious consequences.

INDUSTRIAL ERGONOMICS: Electromyography/Upper Extremity

Effects of user experience, working posture, and joint hardness on powered nutrunner torque reactions BIBAFull-Text 1275-1279
  Jia-Hua Lin; Raymond W. McGorry; Patrick G. Dempsey; Chien-Chi Chang
Powered hand tools produce reaction forces that may be associated with upper extremity musculoskeletal disorders. Fifteen experienced and fifteen novice male powered tool users operated pistol grip and right angle nutrunners in a laboratory study. A full factorial experiment examined the effects of operator experience, working height, distance, tool, and fastener joint hardness on handle displacement and grip forces due to torque reactions. The results show that in addition to working height and distance, experience significantly affected tool handle displacement resulting from reaction torque. Experienced users allowed an average of 7.9°, while novice users allowed 11.5° when pistol grip tools were used on a horizontal surface. Experienced users allowed less handle displacement for all working conditions, and exerted more force than novice users when using right angle tools, but less force when using pistol grip tools. Operator experience influences mechanical exposure during power tool usage.
Muscular Activity During Masonry Work at Various Heights BIBAFull-Text 1280-1284
  Dan Anton; John Rosecrance; Thomas Cook
Masons frequently work with their shoulders elevated and often complain of upper extremity pain. Little is known about the muscular effects of masonry work. The purpose of this study was to evaluate muscular activity while masons laid concrete block at various heights.
   Sixteen experienced male masons constructed a 2.4 m wide and 1.4 m high wall using concrete block. Surface electromyography (EMG) was sampled from the extensor and flexor forearm, and the upper and low back via telemetry. EMG amplitude was determined for the first, third, and seventh courses of block. Analyses of variance were used to test for significance.
   There were no significant differences in the courses for the forearm extensors, forearm flexors, and right low back EMG. Significant differences were found for the bilateral upper trapezius and left lower back, with higher amplitudes at course 7. In this study, masons were exposed to more load in the upper back while laying block at higher courses.
Nonlinear Behavior of Muscle Responses for Four Static Postures Observed at Work BIBAFull-Text 1285-1289
  David Rodrick; Waldemar Karwowski
The primary objective of the study was to explore the nonlinear characteristics of surface myoelectrical activity of the biceps muscle during four static postures observed on the assembly line. The results showed significant differences in the largest Lyapunov exponents between four postures. The surface EMG of the biceps brachii was more chaotic under the maximum loading in MVC posture with elbow fully extended (180 degrees) and static posture with 180 degrees shoulder flexion compared to two other static postures. Based on the Kaplan-Yorke dimension, it was found that dimensional complexity was higher for MVC posture than for posture with 135 degrees shoulder flexion, posture with 180 degrees shoulder flexion, and posture with 90 degrees shoulder flexion and abduction. Interaction effects of posture and trial with respect to the largest Lyapunov exponents and Kaplan-Yorke dimension characteristics of the EMG signals showed higher levels of chaos and complexity patterns in MVC postures compared to other static postures.
Reducing Physical Load and Work Time Using a Pneumatic Drywall Finishing Machine BIBAFull-Text 1290-1294
  Peter Vi
A simulated drywall plastering task was used in this study to evaluate the potential health and safety benefits of using a pneumatic drywall finishing system. The plastering task was performed in a controlled job setting. Muscular exertion while performing the plastering task was measured using electromyography (EMG). Usability questionnaires were given to all participants. Mixed findings were observed for the EMG dependent variables. Significant reduction in the number and duration of muscular rest and static load level were observed for the left forearm flexor muscles when working with the pneumatic tool. However, significant increase in the median and peak load level were observed in the right forearm flexor muscle when working with the Apla-Tech pneumatic tool. The usability questionnaire indicated that a majority of the workers preferred the pneumatic tool. The use of ladders and rolling scaffolds was reduced when working with the pneumatic tool because the tool allowed all workers to reach higher corners and ceiling height. Based on the EMG measures, tool preference and reduction of risk of traumatic slips and falls indicate that the pneumatic tool is an effective tool for applying compound onto drywall joints. Further studies in the field setting to verify the effectiveness of the pneumatic tool should be conducted.
Evaluation of Handle Diameter in Maximum Horizontal and Vertical Torque Tasks BIBAFull-Text 1295-1299
  Yong-Ku Kong; Brain D. Lowe
The effects of handle diameter (25~50mm) and handle orientation (horizontal and vertical) on the subjective comfort, maximum torque performance, total finger force, and efficiency of flexor and extensor muscle activity were evaluated in this study. A force glove system containing 16 force sensors was used to measure finger forces, and surface electromyography was used to investigate muscle activities during torque tasks. Overall 35~45mm diameter handles were rated as most comfortable. The average torque outputs were highest with the 45 and 50mm diameter handles in both orientations. Torque output exhibited a positive non-linear correlation with handle diameter, whereas total finger force showed an inverse relationship with handle diameter. The positive non-linear correlation between torque and handle diameter was explained by the relationship between handle diameter, total finger force, and coefficient of friction. Muscle activities and efficiencies of flexor and extensor muscles were also investigated in this study.


An Analysis of Task-Based Worker Self-Assessments of Force BIBAFull-Text 1300-1304
  Marissa L. Ebersole; Thomas J. Armstrong
Worker self-assessments are an important tool for assessing force and effort in physical work. This study uses maximal grip exertions on a dynamometer to calibrate the workers before rating various tasks' force requirements on a 0 to 10 visual analog scale. 78 workers were selected on 58 different jobs at an automotive assembly plant and asked to rate the separate tasks and the job as a whole. Their peak force ratings (6+2.5) were significantly higher than those estimated by trained observers (4.7+1.1), however they used a larger range of values on the force scale suggesting they were more sensitive to subtle changes. Worker ratings were also sensitive to Hand Activity Level (HAL) changes. Workers on the same job selected the same task to define peak force 86.4% of the time. In conclusion, worker self-ratings can be helpful tool in identifying tasks with high force requirements.
Interrater Reliability of a Video-Based Fixed Interval Sampling Method to Assess Hand Force and Wrist Posture BIBAFull-Text 1305-1309
  Michael H. Lau; Thomas J. Armstrong
Interrater reliability was assessed for a video-based, quantitative exposure assessment method for estimation of hand forces and wrist postures for a short duty-cycle job. Six raters analyzed a 25-second video of a worker packing a case and rated bilateral hand forces and wrist postures at ¼-second intervals. Consistency was analyzed using intraclass correlation coefficients (ICC). Interrater reliability was high for hand forces (left: ICC=0.78; right: ICC0.77), moderate for wrist flexion/extension (left: ICC=0.61; right: ICC=0.59), and poor for wrist deviation (left: ICC=0.15; right: ICC=0.34). For one subtask repeated six times per cycle, force variation was inadequate for ICC calculation, but ICCs were similar for wrist postures (mean ICC=0.55 for flexion/extension, mean ICC=0.39 for deviation). Results indicate raters were consistent in estimating hand forces. Discrepancies in estimating wrist postures were consistent with existing literature. ICCs work well in situations with more variability (i.e. more activity), but not in static, unchanging conditions.
Characterization of Hand Postures Employed by Industrial Workers During Hose Installation Tasks BIBAFull-Text 1310-1314
  D. Christian Grieshaber; Thomas J. Armstrong
Hand posture prediction is an important means of assessing specific task designs prior to subject user trials or actual production. The objective of this study was to estimate the effect of a set of task variables on the observation of hand actions during hose installation tasks in automotive assembly operations. From video recordings of 51 jobs, 124 hand actions were identified. Of these, 50 grasping postures, 70 pinching postures and four non-prehensile postures were observed as the dependent variables. Chi-Square tests revealed significance (p<0.0001) for posture by hose size and posture by hand force (p=0.0007). The use of grasping postures increased significantly when force levels exceeded 40% of maximum. The results support the idea that hand posture is primarily influenced by the size of the object being handled and the amount of force required for performing the task. The results are necessary to further develop taxonomies of grip for predicting hand posture.
Effect of Grip Force on Wrist Range of Motion BIBAFull-Text 1315-1318
  Allison DiMartino; Kathryn Done; Timothy Judkins; M. Susan Hallbeck; Gregory Bashford
This study investigated the effect of a constant grip exertion on wrist range-of-motion (ROM). Seven different levels of grip force were investigated, including two levels of zero exertion, 25%, 50%, 75%, 90%, and 100% MVC. Both hands were tested for each of three forearm positions (pronation, halfway between pronation and supination (neutral), and supination). Twenty student subjects (10 males and 10 females) were tested. Subjects held a particular grip force level constant while simultaneously moving their wrist. The maximum angles of flexion and extension were recorded to measure range-of-motion (ROM). ANOVA analysis was performed for the dependent variables of flexion angle, extension angle, and total ROM. Independent variables were gender, hand, forearm position, and exertion level. Exertion level was a significant factor for extension, flexion, and ROM. Forearm posture was a significant factor for extension and ROM. Tukey-Kramer analysis revealed similar groupings of exertion levels and forearm positions for flexion, extension, and ROM. The data show a significant decrement in wrist ROM as grip force exertion level increased.

INDUSTRIAL ERGONOMICS: Implications of Dynamic Touch for Human Factors/Ergonomics

Implications of Dynamic Touch for Human Factors/Ergonomics: Contributions from Ecological Psychology BIBAFull-Text 1319-1320
  Marvin Dainoff; Jeffrey B. Wagman
The goal of this symposium is to illustrate how research findings from dynamic touch research (i.e., hefting and wielding of objects) within the framework of ecological psychology can have direct and valuable contributions to the field of HF/E. Ecological psychology, as developed by James J. Gibson, shares with HF/E a critical focus on the mutual relationship between person and environment, embodied in Gibson's concept of affordance (i.e., opportunity for behavior). Research in dynamic touch has shown that perceived affordances of hand-held objects are constrained by variables relevant to the task-specific control of the hand-plus-object system. Work on perception of limb position and properties of hand-held objects as well as perception by means of hand-held objects has potential applications in areas such as the design of prosthetics and hand-held tools, remote-controlled or virtual tool use, navigational/perceptual aids for the visually or somatosensory impaired, materials handling, and the design of interfaces.
Dynamic Touch in Varying Media and for Proprioception BIBAFull-Text 1321-1325
  Christopher C. Pagano
The perception of actively manipulated objects via muscle sensitivity has been referred to as 'dynamic touch.' Recent research has indicated that the perception of various properties of occluded objects by dynamic touch is a function of the object's resistances to angular rotation, as quantified by the inertia tensor. Additional findings have generalized this hypothesis to the proprioception of occluded limbs. It is suggested that the mechanisms supporting the perception of intact limbs, prosthetic devices, and hand held tools and implements via dynamic touch may be one and the same -- the detection of movement-produced physical invariants such as the inertia tensor. Research will also be presented showing that the kinesthetic perception of the length of occluded objects remains unchanged when wielding occurs in air or water. This demonstrates that the constancy of perception can be derived from the invariant nature of physical stimulation available to the perceiver, as Gibson (1966) hypothesized. Implications of this work for the design of hand-held tools and attachments to the body are discussed.
Probe Variables for Nonvisual Judgment of Pathway Safety BIBAFull-Text 1326-1329
  Gregory Burton
About 10% of visually impaired Americans use canes to aid locomotion. Prior research has found surprisingly little influence of mechanical variables of these probes on judgments of walkway variables explored with them, and cane users spontaneously report employing various cane substitutes with little decrement. Cane users seem able to adapt to the mechanical variables of their tools, which approach functional transparency to the qualities explored. New research is discussed in which traditional-style aftereffects will be sought in conditions in which participants wield the same probe for several consecutive trials.
Human Factors Implications of Controlling User-Tool-Environment Interfaces BIBAFull-Text 1330-1333
  Jeffrey B. Wagman
When a person grasps an object, they create a hand-plus-object system. In perceiving properties of hand-held objects (including hand-held tools), people seem to show sensitivity to inertial variables relevant to the control of that object. Tool users demonstrate sensitivity to such variables in perceiving (1) whether a hand-held object could be used as a striking implement, (2) where an implement should be brought into contact with another object, and (3) where a hand-held object should be grasped so that object would be most effective as a striking implement. Importantly, tool users show task-specific sensitivity to inertial variables in each case depending on the functional constraints of the striking task (i.e., whether it emphasizes precision over power or vice versa). These findings may be relevant not only to the design of hand-held tools but also to the design of interfaces that allow the remote use of tools (e.g., telesurgery).


Ergonomic Evaluation of Student Computer Workstations BIBAFull-Text 1334-1338
  A. McKinney; E. Kub; M. S. Hallbeck
Student computer workstations have often been overlooked by ergonomists due to their temporary nature of use. Since students usually work at these facilities for a short period of time, ergonomic issues are often overlooked. Four different labs in a university setting were observed for comparison of the actual setup with the "ideal" setup. Placement of the monitor, keyboard, CPU, mouse, and work papers were documented. Postures of students were also taken to compare with the "ideal" posture while working at a computer. Students observed rarely adjusted the setup of the workstation to fit the "ideal" standard.
College Students and Computers: Assessment of Usage Patterns and Musculoskeletal Discomfort BIBAFull-Text 1339-1343
  Karen N. Cooper; Carolyn M. Sommerich; Gary A. Mirka
Time pressure from deadlines, awkward body postures and long-duration, continuous computer use are associated with musculoskeletal disorders (MSDs) in workers using computers. Few studies have examined computer-use-related MSDs in college students. This study investigated computer use patterns of college students, and made comparisons to a group of computer-using professionals. 234 students completed a web-based questionnaire on computer use habits and discomfort students associated with computer use. As a group, students reported their computer use to be at least 'Somewhat likely' 18 out of 24 h/day, compared to 12 h for the professionals. Students reported more uninterrupted work behaviours than the professionals. Younger graduate students reported 33.7 average weekly computing hours, similar to hours reported by younger professionals. Students generally reported more frequent upper extremity discomfort than the professionals. Frequent assumption of awkward postures was associated with frequent discomfort. Results signal a need for intervention prior to entry into the workforce.
Computer Input Devices: Quantification of Use and Variation in Use BIBAFull-Text 1344-1348
  Carolyn M. Sommerich; Sahika Vatan; Amy Asmus
A computer usage monitor (software odometer) was used to collect information on computer input device usage (keystrikes, mouse clicks and movement, and duration of input activity) from 27 professionals, for an average of 17 working days, each. Data from an odometer provides a more extensive means of describing and exploring computer use than more traditional methods, such as self-report of average use in response to a survey question. Further, by collecting data for an extended period of time, considerable day to day variation in computer use was found within subjects. This confirmed the necessity for collecting such data over an extended period of time, and illustrates one of the benefits of the use of software odometers over, or in conjunction with, self-reported usage information via surveys or diaries, or work sampling accomplished through direct observation.
Concrete Leveling Techniques A Comparative Ergonomic Assessment BIBAFull-Text 1349-1353
  Jim Albers; Steve Russell; Kate Stewart
Removing excess concrete and leveling concrete to grade -- a.k.a. concrete screeding -- can be accomplished using a number of different techniques. Five concrete screeding techniques were evaluated to characterize construction workers exposures to risk factors for developing work-related musculoskeletal disorders (WMSD). Workers were videotaped using manual, vibratory, roller, and laser screeding equipment on new construction sites. WMSD risk factors for the five screeding techniques were analyzed using the following ergonomic assessment methods: Posture, Activity, Tools, and Handling (PATH), ACGIH Hand Activity Level TLV, Strain Index, Washington State Ergonomic Rule, Liberty Mutual Manual Material Handling Tables and the NIOSH revised lifting equation. The most serious risks for developing musculoskeletal injuries of the upper extremity and back were observed during manual and roller screeding. Powered screeding techniques generally presented less risk than manual screeding, but these techniques can require brief periods of medium to high exertion for lifting tasks. Vibratory screed operators are exposed to hand-arm vibration, but vibration levels were not measured. Operating the walk-behind and the cab operated laser screeds presented the least risk. Suggestions are provided to limit the use of hand screeding, and to minimize potential exposure to risk factors related to operating and handling the powered screeding equipment.
Ergonomic Laparoscopic Tool Handle Design BIBAFull-Text 1354-1358
  Allison DiMartino; Kathryn Done; Timothy Judkins; Jonathan Morse; Jennifer Melander; Dmitry Oleynikov; M. Susan Hallbeck
Twenty-two subjects were tested and categorized according to hand size (small, medium, or large). Each subject selected the best location for a trackball and a trigger on a handle. Each subject specified the optimum diameter/size of the handle that he or she preferred. Additionally, subjects selected their preferred pivot range for opening and closing the handle. Finally, each subject exerted his or her preferred force for the trackball and trigger controls in the selected positions. Based on the data collected in this experiment, the recommended handle diameter is in the range of 4.3 to 5.7 cm. The recommended handle pivot is the range of 8.1 to 17.3 degrees for the open and closed positions. The recommended trackball actuation force is 3.0 lbs and the recommended ratchet actuation force is 0.6 lbs, on average.
Evaluation of Laparoscopic Tools for Usability and Comfort BIBAFull-Text 1359-1362
  Kathryn Done; Allison DiMartino; Timothy Judkins; Susan Hallbeck; Dmitry Oleynikov
Many problems have been associated with current laparoscopic surgical tools, and work is being done to improve the design of many the tools and devices, but little improvement has resulted. The IDEA Lab at the University of Nebraska-Lincoln, has designed a comfortable and intuitive tool with added function as a result of questionnaire responses from student and expert surgeons. Surgeons were asked to respond to a questionnaire asking about pain and discomfort experienced from use of conventional laparoscopic grasper tools. Analysis of the results shows that more than 25% of all respondents experience problems during or after surgery in the following areas: neck pain and stiffness, shoulder/arm pain and stiffness, hand/wrist pain and stiffness, back pain and stiffness, mental fatigue, awkward manipulation of instruments, and performing precise movements. Eleven out of eighteen surgeons reported experiencing painful areas of the hand during or after laparoscopic surgery, including but not limited to, numbness of the thumb and soreness of the fingers. These results make it clear that the redesigns of the new laparoscopic grasper tool were needed. Further testing will be conducted to compare the new design to conventional tools and determine if all of the needs of surgeons have been met.

INDUSTRIAL ERGONOMICS: Practice-Oriented Session

Ergonomic Evaluation of U.S. Army Bridge Construction BIBAFull-Text 1363-1367
  Andrew S. Bodenhamer; Bradley M. Davis; Roshan S. Kotian
An ergonomic intervention of the construction of the Medium Girder Bridge was conducted. In this study, task observation, a sample survey, ergonomic assessment, and ergonomic intervention were conducted. Survey results were collected (n = 58), and served to identify the population and areas for ergonomic improvement. The revised NIOSH lifting equation and University of Michigan 3D Static Strength Prediction Program were then used to analyze manual materials handling tasks. By redesigning the hand tools used for bridge construction, the average NIOSH lifting index was decreased by 0.4 (-16%) and the average L5/S1 disc compression was reduced by 1700 N (-36%). These results along with other ergonomic improvements will be validated in a pending field study.
Comparing Results of Four Lifting Analysis Tools BIBAFull-Text 1368-1372
  Steven Russell; Lori Winnemuller; Janice Camp; Peter Johnson
Four lifting analysis methods (WA L&I, NIOSH, ACGIH TLV, and 3DSSPP) were used to assess milk case stocking of 4- and 6-gallon cases. The outputs of each method were converted to a risk index similar to NIOSH's Lifting Index and used to contrast and compare risk predictions. All instruments showed higher risks associated with lifting the 6-gallon cases versus the 4-gallon cases. The NIOSH and ACGIH TLV methods were virtually identical in their results and predicted substantially higher risk when compared to the 3DSSPP. WA L&I showed risk only at the higher lifts, but its threshold for risk was designed to be higher for regulatory purposes. NIOSH's multi-task analyses were also performed. For the practitioner, the ACGIH TLV is a simpler tool to use and yields results similar to the NIOSH single-task analysis for this type of lifting, but NIOSH offers greater interpretive capabilities. All of the instruments may underestimate the risk of this lifting task due to the presence of factors unaccounted for in their calculations. The differences, strengths, and limitations of each method are outlined.
Industrial Ergonomics Tool Use by Certified Professional Ergonomists BIBAFull-Text 1373-1377
  Patrick G. Dempsey; Raymond W. McGorry; Wayne S. Maynard
A survey of Certified Professional Ergonomists (CPEs) was conducted to gather information on the types of basic tools, direct and observational measurement techniques, and software used by practitioners. The results of the industrial ergonomics tools are reported here. A high percentage of respondents reported using tape measures, video cameras, stopwatches and digital cameras. The most commonly used observational methods were those involving manual materials handling, whereas the most commonly used direct measurement tools were pinch and grip dynamometers and push/pull gauges. The type of checklists, software, and anthropometric data used also are summarized, and potential reasons for use, or lack of, are discussed.
Efficient Flow and Human Centred Assembly by an Interactive Approach BIBAFull-Text 1378-1382
  Sandra M. Eikhout; Rianne B. M. Helmes; J. W. van Rhijn
Due to fluctuations on the market, manufacturing of many product variations, and wish for fine-tuning between production and assembly a fan and motor manufacturing company wanted to improve their assembly line. The aims were efficient flow and human centered assembly in the new product line. Therefore an integral participatory approach of ergonomics and assembly engineering was adopted. This paper describes the process and the results of the development of the new assembly line. The new defined assembly line leads to productivity increase, less physical load, less walking and searching time, efficient flow, flexible deployment, ergonomic workstations and convenient arrangement of workstations, material and transportation.
A Linear Programming Model for Workstation Adequacy BIBAFull-Text 1383-1387
  Avaneesh Gupta; Mei Zhang; Ravindra S. Goonetilleke
Workstation design can have a profound effect on an individual's health. Most product designs are based on a 5th percentile "reach" and a 95th percentile "clearance". These designs quite often fail to match a person's body measurements since the dimensions of each body link are not exactly the same xth percentile. Even with an adjustable workstation, the user has a dilemma as to what adjustment to make for each adjustable parameter as each adjustment depends on the previous adjustment and the potential number of adjustments is somewhat infinite. This paper focuses on a methodology to achieve a postural fit for a given workstation with an adjustable table, chair, and footrest. The least stressful and somewhat comfortable postures were first determined from the literature. Thereafter, a Linear Programming model was developed to capture these mappings as mathematical constraints and solved. The model was validated with an adjustable workstation and a few participants.


Effects of Work Conditioning and Adjustment Period on Psychophysical Estimates in Manual Torquing Tasks BIBAFull-Text 1388-1392
  Deepti Sood; Maury A. Nussbaum; Kari L. Babski-Reeves
Several issues must be addressed in experiments using psychophysical estimations, including the potential effects of work conditioning, the necessary adjustment period, and the validity of experimental results. To address these, two experiments were conducted that simulated different manual torquing tasks. In the first experiment, 16 participants provided their maximum acceptable repetition rate (MARR) in a 2-hour adjustment period, and repeated this for five consecutive days. No significant differences were found across days (i.e. no work conditioning effect). Further analysis indicated that results after 12 minutes were comparable to those at 2 hours. In the second experiment, another set of 16 participants provided estimates of 2-hour MARRs in a 12-minute adjustment period for two task conditions. On subsequent days they worked for 2 hours at their self selected MARRs. Participants were able to perform the tasks at their MARR with low to moderate average ratings of perceived discomfort on these latter days, supporting the use of a short (12-minute) adjustment period.
Abdominal Belts and Low Back Position Sense BIBAFull-Text 1393-1396
  Kelly D. Briant; Sara E. Wilson
Abdominal belts are sometimes used as a low-cost, low back injury prevention measure in industry. Claims for the effectiveness have suggested that such belts may enhance proprioception and therefore improve low back stability. In this study, this claim was examined by using a previously established low back reposition sense protocol to assess the change in position sense with use of an elastic back belt in both an upright and a flexed posture. The results of this study demonstrate no overall improvement of position sense with back belt. However, significant improvement was observed at a torso flexion angle of 45 degrees. While future studies in other conditions are suggested, this study suggest that back belts may be useful only when highly flexed postures are required for manual materials handling.
Relation Between Whole-Body Postural Discomfort and Body-Part Postures for Working Postures of Automobile Assembly Tasks BIBAFull-Text 1397-1401
  Inseok Lee; Min K. Chung; Young-Woong Song
Observational methods have been widely used for identifying posture-related risks in industry. In those methods, a single score of postural load for a working posture is required for evaluating the level of corrective actions, on the basis of each body-parts stressfulness evaluated. However, most existing methods have transformed stressfulness for several joints into a postural load based on subjective judgments of ergonomic experts, not on an objective basis. In this study, the relationship between body-part postural load and whole-body discomfort for working postures was investigated. A laboratory experiment was conducted to evaluate static postures frequently assumed during the automobile assembly tasks, based on perceived discomfort. The results showed that the postural load was strongly associated with the combination of discomfort for non-neutral joint postures. The more joints severely deviated from neutral position were involved in a working posture, the higher level of the whole-body postural discomfort was imposed. In a regression analysis, the relationship was quite well fitted with a linear model, in which shoulder motion was found to be the most affecting factor on the whole-body postural stresses. The linear relationship is expected to be useful for better understanding adverse effect of joint motions on a whole-body posture.
The Effects of Distance on Psychophysically Determined Pushing and Pulling Tasks for Female Industrial Workers BIBAFull-Text 1402-1406
  Vincent M. Ciriello
The most frequent and expensive cause category of compensable loss is manual material handling (MMH). In an attempt to minimize these losses, refinement of existing MMH guidelines is a component of redesigning high risk MMH jobs. In the development of our present MMH guidelines (Snook & Ciriello, 1991), maximum acceptable forces (MAFs) of pulling were assumed to respond similarly to pushing at longer distances for male and female industrial workers. The purpose of this experiment was to investigate the effects of 7.6m and 15.2m distances on both initial and sustained MAFs of pushing and pulling at a frequency of 1 min-1. A psychophysical methodology was used whereby the subjects were asked to select a workload without "straining themselves or without becoming unusually tired, weakened, overheated or out of breath." Ten subjects worked 40 min at each push or pull task within a 4-hour test that included other MMH tasks. The results revealed that initial and sustained MAFs were not significantly different between pushing and pulling at both the 7.6m and 15.2m distance. However, task time was significantly longer for pulling at both distances. It was concluded that our existing guidelines present an accurate estimate of MAFs at the longer pull distances for female industrial workers.
An Investigation of the Congruity in Geometry of the Glenohumeral Joint on the Maximum Acceptable Load During Pushing BIBAFull-Text 1407-1411
  Krystyna Gielo-Perczak; Simon Matz
One of the most interesting topics in occupational research for musculoskeletal disorders is an investigation into why individuals respond differently to pushing forces taking into account their strength. The study reports the results of the strength of 12 subjects during one-handed pushing and the geometries of their shoulder joints derived from magnetic resonance imaging (MRI) scans. The measurements of mean force during pushing were recorded when the upper right arm was abducted in the frontal plane from 5 to 30 degrees during maximum voluntary contraction (MVC). The three characteristic shoulder types A, B and C were identified in the group: type A -- glenoid with a radius that is larger than that of the humerus, type B, glenoid and humerus with the same radius, and type C, glenoid with a radius that is smaller than that of the humerus. The congruency of the shoulder joint is not a straightforward related factor on the maximum acceptable load during pushing. There may exist other geometric relationships between the anatomic variables which have influence on the maximum load during pushing.

INDUSTRIAL ERGONOMICS: Quantification of Exposure

A Preliminary Field Assessment of the Energy Expenditure of Forestry Workers in South Africa BIBAFull-Text 1412-1416
  P. A. Scott; C. J. Christie
Internationally forestry is recognized as encompassing some of the most physically demanding and hazardous jobs. While extensive research has been conducted in many advanced forestry areas, very little has been done in South Africa where a multi-ethnic manual work force has to operate in sub-optimal working and climatic conditions. This paper will present the findings of a preliminary investigation conducted on Chainsaw operators (Felling and Cross-cutting) and Stackers working in the tropical north of the country where ambient temperatures and humidity are high. The vast majority of these workers come from meagre living conditions with a very low nutritional intake and associated health problems all of which have a substantial negative impact on worker efficiency. The results reveal that with mean working heart rates and energy expenditures of 135 bt.min-1 (8.54 kcal.min-1) and 137 bt.min-1 (9.21 kcal.min-1) for the Chainsaw operators and Stackers respectively, the job requirements fall into the categories of 'very heavy' to 'unduly heavy' placing extreme stress on the cardiovascular and musculoskeletal systems of these manual labourers, and showing a clear need for sound ergonomics intervention.
Low Back Disorder Risk in Automotive Parts Distribution BIBAFull-Text 1417
  Steven A. Lavender; Denise M. Oleske; Gunnar B. J. Andersson; Mary Morrissey; Phyllis Zold-Kilbourn; Emily Taylor
The purpose of this study was to characterize the low back disorder (LBD) risk in jobs found in automotive parts distribution centers. This descriptive study analyzed 53 jobs at 7 automotive distribution facilities in the Northern United States. Data were collected using the Lumbar Motion Monitor (LMM) and analyzed using the LMM LBD risk model. Historically, the LMM risk model, which was developed primarily through an analysis of manufacturing jobs, has used the peak load moment in the calculations. A secondary purpose of this study was to compare the difference in LBD risk estimates obtained using the peak versus the mean load moment in the analysis of these highly variable lifting jobs. Given that each lifting task may be a different weight item from a different location the sampling process was validated using split-test reliability coefficients. These were found to be 0.90. Results indicate that, on average the jobs in automotive parts distribution are moderately high risk (mean = 56%, s.d.= 11%), however, nearly half the sample had LMM LBD risk probability values greater than 60% mark that has been used by some as a cut point in defining "high" risk (Marras et al., 2000). On average, use of the average moment instead of the maximum moment reduced the LBD risk probability value by 7.4 percent (s.d.= 5.3%), however, the range included no difference up to 17 percent. Many of the jobs contain trunk motions that are associated with high LBD risk, however, many of these same jobs had relatively low lifting frequencies which moderated the risk estimates. It should be noted that for many of the jobs the LBD risk probability was at the medium level due to the travel time required between lifts. This kept the frequency of lifting in many of these jobs relatively low for distribution type work; for many jobs the liftrates were less than 60 lifts per hour. The liftrate potentially contributes 20 percent to the overall risk calculation in the model. This suggests that efforts to increase the pick rates and efficiencies in these jobs will be accompanied by increased LBD risk if done without accompanying ergonomic interventions.
Characteristics of Job Rotation in the Midwest U.S. Manufacturing Sector BIBAFull-Text 1418-1422
  Michael Jorgensen; Kermit Davis; Prabahran Veluswamy; Carrie Ekrut; Susan Kotowski
Job rotation has been advocated as a business practice to increase the skill of employees, as well as a suitable intervention for the control of work-related musculoskeletal disorders. However, little is known regarding the prevalence of job rotation, methods used to identify jobs to rotate to, or the benefits or limitations of job rotation. A web-based questionnaire was developed to survey job rotation practices in the Midwest U.S. manufacturing sector. Results indicated that 42% of the companies contacted use job rotation, and that companies appeared to be using job rotation on a permanent basis. Job rotation was used mainly to reduce exposure to risk factors and reduce work related injuries, whereas methods utilized to identify jobs to rotate to were based mainly on supervisor decision and ergonomic job analysis. These findings suggest further study is needed to determine if exposure to risk factors is being reduced through current efforts.
Quantitative Representation of Alternative Movement Techniques and Motion Variability BIBAFull-Text 1423-1426
  Woojin Park; Don B. Chaffin; Bernard J. Martin; Ashraf M. Genaidy
In an attempt to objectively represent and differentiate movement techniques, and further understand the variability in human motion behavior, this study presents a quantitative index termed Joint Contribution Vector (JCV) representing a motion in terms of contributions of individual joint degrees-of-freedom to the achievement of the task goal. Given a set of uncharacterized motions, the JCV index and statistical visualization and clustering methods enable identification of alternative movement techniques and graphical representation of motion variability. A motion data analysis was conducted to demonstrate the utility of the JCV index.
Physical Load Estimation of Flight Attendant Work by Direct Observation and Accelerometry BIBAFull-Text 1427-1430
  L. A. MacDonald; J. Deddens; E. A. Whelan; B. Grajewski
Occupational groups with variable work tasks pose unique methodological challenges to ergonomists who need valid measures of physical job demands for occupational health research. In this study data on flight attendants' physical job demands were collected during five round-trip commercial passenger flights using direct observation and accelerometry. Thirty-five flight attendants (88% participation) each were observed inflight and equipped with two accelerometers (positioned on the leg and waist). Correlational analyses were performed to examine concordance between measures obtained by each method. Agreement was moderate to high between direct observation and accelerometry for measures of standing, lifting (leg), and overall physical effort level. Agreement was poor for back posture and push/pull activities. These findings suggest that accelerometry may provide an acceptable alternative to the labor-intensive but established observational approach when evaluating some physical job demands in occupational groups with variable work. However, supplementation of accelerometry with descriptive data from other methodologies (e.g., exposure diary, questionnaire, focus groups) is warranted to provide important information regarding the nature of workers' exposure to postural loading, exertion demands and task activity.


The Influence of an Inclined Surface on Flat Surface Postural Control BIBAFull-Text 1431-1434
  Lloyd R. Wade; Wendi H. Weimar; Jerry Davis
An epidemiological study conducted by the NTOF surveillance system of the National Institute of Safety and Health (NIOSH), analyzed 15 years of data (1980-1994) to identify work settings in which fatal falls were likely to occur, and the risk factors that contributed to those falls. Eight thousand one hundred and two (8,102) workers were reported to have died as a result of falls from elevations during the 15-year period. The construction industry accounted for 4,044 of those deaths, or roughly 50% of all fatal falls from elevations. Within the construction industry sub-group (NAICS 23611), the NTOF identified general contracting and roofing as the work setting with the highest risk factors for a fall from elevation, with 205 and 147 falls respectively. The purpose of this study is to examine the effect that locomotion on an inclined surface has on flat surface postural stability. All subjects who volunteered as participants (n=20; males), were tested under two walking conditions: flat surface and inclined walking on a 12 x 15' pitched roof segment to determine if there was a difference in sway velocity following exposure. Data were collected over four, ten-second trials, under eyes open and eyes closed conditions. Performance was measured using the recordings made by the NeuroCom Balance Master System. Balance was recorded in sway velocity (degrees/second), where the value was representative of the change in center of gravity (COG) in the anterior, posterior, medial, or lateral directions. The angular change of the COG per unit time was summed and divided by ten-seconds to achieve an average sway velocity of the COG. These data were evaluated using a 2 (pre/post) x 2 (eyes) x 2 (flat walking, inclined walking) within-subjects repeated measures analysis of variance (ANOVA), with the dependent variable being sway velocity (deg/sec). Paired sample t-tests served as post hoc analysis. The analysis concluded that the average sway velocity of the COG resulted in a significant main effect following the inclined walking task: p ≤.001. The findings have practical implications when dealing with the construction industry. On a daily basis, roofers ascend and conduct roofing related tasks for prolonged periods of time. Following exposure to the pitched roof setting, roofers must move from the roof to scaffolding or a ladder to descend. These findings suggest that there is a significant decrement in postural stability due to exposure to inclination. Postural stability is critical in ascending and descending ladders and scaffolding on flat surfaces. Possible areas of future research that might impact postural stability could potentially involve roof jacks, work boot design, and work rest cycles.
Age-Related Differences in Shoulder Isometric Endurance, Fatigue, and Recovery BIBAFull-Text 1435-1439
  A Yassierli; Maury A. Nussbaum; Hardianto Iridiastadi
Despite projections of a substantial increase of older adults in the working population, studies addressing the effects of age on muscular performance are still limited. The purpose of this study was to examine age-related differences in muscular endurance, fatigue, and recovery during prolonged static exertions. Groups of 24 younger and 16 older participants performed isometric arm abductions until exhaustion at 30, 50 and 70% of individual strength. Recovery was determined over 15-minutes following the end of the exercise. Electromyographic signals obtained from the middle deltoid muscle were used to evaluate fatigue progression during the exercise. Compared to the younger participants, the older individuals exhibited lower muscular strength, longer endurance time, slower fatigue progressions, less reduction in muscle strength, and shorter recovery periods. This study suggests that fatigue-related differences exist between age groups, and the results may be used to better design task for older workers.
Effect of Whole Body COM Velocity on Friction Demand BIBAFull-Text 1440-1443
  Sukwon Kim; Thurmon Lockhart; Hoon-Yong Yoon; Min-Yong Park
The study was conducted to evaluate relationships among walking velocity, heel contact velocity, and friction demand. Particularly, the study attempted to ask if two age groups (younger and older groups) differed in walking velocity and heel contact velocity, and how these gait parameters influenced friction demand characteristics in two age groups. 14 younger (7 females and 7 males, 18 to 30 years old) and 14 older (7 females and 7 males, over 65 years old) adults participated in the study. Kinematic and kinetic data were measured using 6 infrared cameras and 2 force plates mounted on the walking track. The primary goal of the study was to evaluate if walking velocity (whole body COM velocity) and heel contact velocity with advancing age influenced friction demand characteristics. The results indicated that older adults walked slower, exhibited lower heel contact velocity, and produced lower friction demand in comparison to younger adults. The study suggested that walking velocity could be a good indicator for predicting friction demand characteristics.
Role of Ankle Joint in Successful Reactive-Recovery: A 3D Joint Moment Analysis BIBAFull-Text 1444-1448
  Jian Liu; Thurmon E. Lockhart
Understanding successful reactive-recovery is essential to further exploration of slip induced fall event. The objective of the current study was to characterize the net ankle joint moment pattern during reactive-recovery process. Six out of fifteen healthy young adults were selected as input for the current investigation. The three-dimensional (3D) inverse dynamics approach was applied to calculate net ankle joint moments in all the three planes (frontal, sagittal and transverse). Gait conditions (normal and reactive-recovery) significantly affected the absolute ankle peak moment and time to peak at P ≤ 0.05 level. The time to peak in the ankle frontal plane was the only one not affected. The ankle frontal and transverse joint moment was found to play an important role during the reactive-recovery process. Consequently, the necessity of a complete 3D joint moment analysis especially for slip and fall incidents was justified.
Relationship Between Slip Distance and Perceptions of Slipperiness and Stability BIBAFull-Text 1449-1453
  Angela DiDomenico; Raymond W. McGorry
Falls precipitated by slipping are listed among the leading causes of occupational injuries. Several factors influence the risk of slips and falls, including perception of surface conditions. A study was conducted to investigate if perceptions of slipperiness and stability are related to slip distance at heel strike during normal walking. The investigation compared objective and subjective measures for thirty-one participants ranging in age from 19-67 years old. Participants were evaluated while walking at three velocities over three floor surfaces. The results indicated that there were significant differences in slip distance caused by floor surfaces, but perceptions did not reflect these changes. Correlations between slip distance and subjective evaluations of slipperiness and stability were r = -0.18, partially due to a large variability in perceptions between individuals. Small slips were not generally perceived, but a uniform cutoff distance could not be identified that would be appropriate for most individuals.


A 3D Motion Prediction Model for Arm Movement BIBAFull-Text 1454-1458
  Yanxin Zhang; Simon M. Hsiang
A mathematic prediction model based on numerical method is investigated for human arm-reaching movement. Unlike the previous solutions that optimized certain cost functions with global nonlinear multi-constraints of the kinematics and kinetics, the model applies Listing's Law to reduce the degrees of freedom. The rotation vectors, which describe arm positions as a rotation relative to given reference positions, are confined to a flat range called Listing's plane. The major benefit of this model is that it is biologically plausible and supported by other experimental results and the model requires little computation aim to find a feasible, not necessarily optimal path; therefore, make it more applicable for biomechanical simulation. The anatomical assumptions and the model development are detailed and a validating experiment was conducted. The result of experiment shows that the proposed method generated the motion trajectory with reduced calculation complexity.
A New Three-Dimensional Model for Predicting Hand Prehensile Configurations BIBAFull-Text 1459-1463
  Sang-Wook Lee; Xudong Zhang
An optimization-based three-dimensional (3D) model for power grip posture prediction was proposed. The model was based on the premise that the hand prehensile configuration in a power grip best conforms to the object shape. This premise was embodied by an optimization procedure that minimized the sum of distances from the finger joints to the object surface. The model was evaluated against data from an experiment that measured the grip postures of 28 subjects having diverse anthropometry. The intra- and inter-person variabilities in grip postures were empirically assessed and used as benchmark values for model evaluation. The evaluation showed that the root-mean-square (RMS) values of angle differences between the predicted and measured postures had a 13.7° grand mean (across all joints, subjects, and two cylindrical handles grasped), whereas the RMS values of the inter-person and intra-person variabilities in measured postures had grand means of 13.0° and 4.4°, respectively. The model can be readily generalized to the prediction of postures in power-grasping objects of different shapes, and adapted for testing alternative prehensile strategies or performance criteria.
Effect of Handle Design and Target Location on Wrist Posture During Aiming with a Laparoscopic Tool BIBAFull-Text 1464-1468
  T. N. Judkins; A. DiMartino; K. Done; M. S. Hallbeck; D. Oleynikov
Laparoscopic surgery is a rapidly increasing field in healthcare today. However, current laparoscopic tools have inadequate handle designs and have been directly linked to post-surgery pain among surgeons. This study recruited forty subjects (20 male, 20 female) to evaluate the effect of handle design as well as target location on accuracy, precision, and wrist posture during an aiming task. Two laparoscopic tools were used for this study: a commercially available scissor-grip tool and a custom-designed ergo-grip tool. Each subject was asked to aim through a trocar at the center of one of five targets using one of the tools. The target was viewed by a laparoscopic camera and presented on a television. The results of this study showed that accuracy and precision were affected by both target position and tool; however, the differences were small (<2 mm). Wrist flexion and ulnar deviation angles were affected by both target position and tool. Differences due to target position were expected given different hand locations are required to hit each target. Flexion angle was significantly smaller for the ergo-grip tool as opposed to the scissor-grip tool. Ulnar deviation angle was significantly smaller for the scissor-grip tool than for the ergo-grip tool. All but one subject preferred the ergogrip tool when performing the task, suggesting that wrist flexion is a stronger predictor of comfort than ulnar deviation though both should be considered when designing ergonomic hand tools.
Effect of Graphic Input Device and Repetition on Wrist Posture BIBAFull-Text 1469-1473
  Janice Serafine Lilien; Emily H. Wughalter
This study investigated the Wacom Intuos2 pen and tablet and/or standard Microsoft mouse on wrist posture of 20 experienced users. Wrist posture, measured by extension, flexion, ulnar, and radial deviation, was compared across three independent variables: repetition (repetitive or alternative), input device (mouse and/or pen), and session (session 1 and session 2). Devices were used during a graphical computer task, which was repeated or alternated for two 30 minute test sessions. Neutral wrist range was defined within 15 degrees of 0 in any direction. Input device group interacted with session to significantly impact wrist extension, F (3,16) = 9.42, p<.001 and ulnar deviation, F (3, 16) = 3.23, p <.05. When analyzing repetition while using the mouse, less extension was found than the pen. Both devices required movement outside the defined neutral range for extension. A significant repetition by session interaction effect for wrist flexion was revealed: F (1, 16) = 6.83, p <.05. The repetitive group revealed little to no flexion during the first session which was statistically different than the alternative group; both groups were inside the neutral range.

INTERNET: Applications

Cell-Phone Voting: An Interface and Concept Evaluation BIBAFull-Text 1474-1477
  Shantanu Pai; Gulshan Panjwani
Currently, voters must physically go to voting booths to participate in civic elections. Among others, a busy lifestyle and inability to make it to the voting booths has been cited as one of reasons for a low voter turnout. This has prompted research concentrating on the use of Internet for voting. Internet has its limitations in availability and mobility. We propose a cell-phone based voting system that could potentially overcome these limitations. A within-subject usability study compared a prototype cell phone based UI with a PC based UI. Eight participants completed the task of casting a vote using the two interfaces and rated them on various dimensions. Results indicate that the concept although acceptable, has social and security concerns. With the cellphone interface, limited information displayed and global navigation were identified as prime drawbacks. Research on explicit CHI patterns for cell interfaces may address the CHI issues identified.
Promoting Memorability and Security of Passwords Through Sentence Generation BIBAFull-Text 1478-1482
  Kim-Phuong L. Vu; Bik-Lam (Belin) Tai; Abhilasha Bhargav; E. Eugene Schultz; Robert W. Proctor
Much of our personal information flows through the Internet as we receive online services or make online transactions, making it essential to have reliable security systems to protect against information theft, denial of service, and fraud. The most commonly used method for authentication and identification is entering the username-password combination. However, this method is weak because users select passwords that are easy to remember and easy to crack. We evaluated a sentence-generation method designed to improve recall and security. The sentence-generation method produced crack-resistant passwords when the users were instructed to embed a digit and special character into the sentence (and password). However, the requirements of including a digit and special character also resulted in a cost in the memorability of the password. An analysis of errors identified three areas of research that may develop techniques that promote better recall of passwords using this sentence-generation method.
Remote Contextual Inquiry: A Technique to Improve Enterprise Software BIBAFull-Text 1483-1487
  Jeff English; Lynn Rampoldi-Hnilo
It is difficult to evaluate the usability of large-scale enterprise software because it is customized to each company's business process when it is implemented. Remote Contextual Inquiry is a research technique that allows software teams to remotely view how software users interact with the system and the types of software customizations that have been made. Understanding how users interact with the software and the types of customizations made during implementation can help designers and product managers prioritize existing features for redesign and describe the need for new features.
Design and Management Techniques for Creating Web-Based Applications BIBAFull-Text 1488-1492
  Sam Racine; John P. Curtin
The Web environment produces new challenges for Human Factor specialists who are transitioning their development organizations and clients from traditional software media to Web-based applications. While the Web offers new potential for deployment, its technical capabilities often limit techniques for user interaction and data manipulation PC-based GUIs offer. Conventions for operation of web applications are still ill-formed; concepts for website design rarely translate well to the design of task-based, enterprise-level applications; and stakeholders often mistake their own, idiosyncratic operation of websites as premises for effective design. This paper teaches practitioners techniques for creating or migrating software applications from traditional media to the Web, based on a case study of creating a web-access cargo management system. Discussion includes dealing with unrealistic visions of an application's operation in relation to the user population who will be operating it, developing alternatives to traditional forms of personnel training, and creating new controls and interaction schema.
Usability Testing of an Internet form for the 2004 Overseas Enumeration Test: Iterative Testing Using Think-Aloud and Retrospective Report Methods BIBAFull-Text 1493-1497
  Kent L. Norman; Elizabeth D. Murphy
An Internet form for the U. S. Census Bureau's 2004 Overseas Enumeration Test was evaluated in two rounds of usability testing. Participants were assigned to one of two conditions: Think-Aloud, in which they talked about what they were doing; or Retrospective-Report, in which they completed the form and then talked about their experience while viewing a recording. Participants also completed follow-up tasks. Sessions were video taped and logged. Round 1 testing identified 28 usability issues. Round 2 testing found that 13 of the issues had been resolved following design changes made to the interface. Round 2 testing identified 21 new and continuing usability issues. Results suggest that changes made to the interface increased the likelihood that respondents would be able to successfully complete the form. Task completion times in the think-aloud condition were only slightly longer than they were in the retrospective condition, while retrospective reports required a substantial amount of added time.

INTERNET: E-Commerce

Visualizations to Facilitate Online Tabular Presentation of Product Data BIBAFull-Text 1498-1502
  Marc L. Resnick; Carlos Fares
In a growing number of domains, users are presented with huge volumes of data that they are required to parse in order to accomplish their goals. Interface designers are experimenting with a variety of design manipulations to facilitate user's identification and analysis of these data. Many domains present information in grids, such as the side-by-side comparison of products prevalent at many e-commerce web sites. Further assistance can be provided by using color-coding, ranking systems and other visualization techniques. This study investigates the use of color-coding and ranking on tasks that require either focused or integrative analysis of tabular data. The results show that each provides some benefit, but color-coding is superior. The presence of both manipulations degrades performance, suggesting some degree of information overload. Furthermore, despite the prevalence of these techniques, instructions that explained how they were relevant to the task were necessary to achieve the performance improvement. The implications of these results are discussed.
Persuasive Design Through Intelligent Recommendation Systems BIBAFull-Text 1503-1507
  Marc L. Resnick; Sheryda Pompa; Isaac Korn; Omar Castillo
Collaboration between human factors and marketing can have a significant impact on the profitability of retail, particularly on the Internet where comprehensive information systems can be used to model customer and product relationships. This paper presents a case study through which the capabilities of intelligent recommendation systems to achieve persuasive design are demonstrated. A web site for a department store was created that provides targeted recommendations to customers based on functional relationships between products and customer profile information where available. The site was designed to present only recommendations that closely match the needs of the customer and establish a trusted relationship. An empirical study was conducted to verify that the goals of the site were attained. Participants rated the recommendations as relevant, unobtrusive, and reported an enhanced shopping experience. Privacy requirements were also maintained. This case study demonstrates that understanding and designing for the needs of the customer can significantly enhance the opportunity to increase sales to online retail customers.
Modeling User Satisfaction, Frustration, and User Goal Website Compatibility BIBAFull-Text 1508-1512
  Sandra K. Garrett; Diana B. Horn; Barrett S. Caldwell
Users often come to websites with a specific type of purpose or goal, which defines how the user interacts with the site. Two types of task-goals addressed in this study include general browsing and specific information seeking. Likewise, the design and organization of different websites can facilitate different user goals. User satisfaction and frustration from interacting with a particular website depends on the compatibility between the website design and the user's type of goal. This study applies simulation techniques to investigate how the compatibility between user goals and website design impacts user satisfaction and frustration levels. The simulation results show that navigation tools that increase compatibility versus attractiveness (the increased likelihood of use) have a greater impact on customer satisfaction and could in turn maximize the effectiveness of website usage.
A Comparison of Three-Level Web Menu Navigation Structures BIBAFull-Text 1513-1517
  Jennifer R. Kingsburg; Anthony D. Andre
This research addresses the topic of three-level menu structures, now commonly found in e-commerce web sites, by measuring the performance and preference effects of different menu location combinations. Two studies were conducted, each using 16 different participants. The first study compared combinations of left and top menu positions across three menu levels. The results indicated a benefit when the first (primary) menu level was located on the left side of the screen, and when second and third menu levels were grouped in the same plane, opposite from the primary menu. The second study included a comparison of right-side menus. The results confirmed the benefit of grouping the second and third menu levels in the same plane, and suggest the value of locating the primary menu level on the right side. Finally, users preferred primary menus that were located in the left or right planes rather than the top plane. The results have important implications for the design of multi-level web site menu structures and represent a first-step towards providing empirical-based guidelines to site designers.

INTERNET: Finding Information Online

Evaluating the Effectiveness of Automated Assistance for Web Searching BIBAFull-Text 1518-1522
  Bernard J. Jansen; Michael D. McNeese
Web search engines offering personalized automated assistance have the potential to improve the searching process. We report the results of a within subjects, counter balanced empirical evaluation to determine whether automated assistance improves searching performance. Thirty subjects interacted with two fully functional, information retrieval systems. The systems were identical in all respects except that one offered automated assistance while the other did not. The study used a client side automated assistance application, a 2G Text REtrieval Conference document collection and six topics. Results from the empirical evaluation indicate that automated assistance can statistically improve searching performance; however, the improvement is not as dramatic as one might expect, with an approximately 20% performance increase, as measured by number of relevance documents retrieved. We discuss the implications for Web systems and future research.
Improving User Search with Embedded Boolean Search Hints BIBAFull-Text 1523-1527
  Jennifer Bandos; Marc L. Resnick
Because of the extensive use of search engines on the Internet, even small improvements in usability can lead to huge benefits in productivity and effectiveness. Unfortunately, Internet users have consistently shown that they are unable or unwilling to use Boolean operators effectively. This paper presents an investigation of the use of embedded Boolean search hints to improve user search query construction. These hints consist of short, targeted in-line messages that present task-focused instruction on the use of Boolean operators. Three types of help content were studied: semantic, syntactic, and exemplar. The results indicate that inline help can significantly improve performance. However, the improvement was produced only when the content specifically matched the users' needs. Furthermore, some unexpected results suggest that users' experience with other Boolean interfaces can impair performance. Implications for search interface design are discussed.
User-Centered Design of a Customized Intranet Portal for a Large Public University BIBAFull-Text 1528-1532
  Marc L. Resnick; Walid Bakar; Mauricio Castellanos; Reza Haghighi; Andrea Monsalve
Intranet portals can provide a centralized source of company information, web applications, and external links that are customized for the needs of each employee, increasing employee productivity and effectiveness. However, they are only effective when they support user needs in an effective and usable fashion. In 2003, Florida International University (FIU) began the process of creating an intranet portal for use by its 34,000 students. The portal would provide web-based email functionality along with profile-driven University information and preference-based external links. This is expected to increase student use of the FIU email system, facilitate dissemination of FIU information to students, improve achievement of educational goals, streamline university processes such as registration, provide cost savings to the university, and increase student satisfaction. This paper describes the user-centered design process that was used to create the MyFIU portal and provides guidance for the development of Intranet portals.
The Human-Web Interaction (HuWI) Cycle: A Framework of Users' Perception, Action, and Cognition on the Web BIBAFull-Text 1533-1537
  J. Shawn Farris; Keith S. Jones
Since its inception, the World Wide Web has flourished. While advances have been made in the general area of web usability, little attention has been paid to developing theories of human-web interaction. Accordingly, Neisser's (1976) perceptual cycle, which unifies research on action, perception, and cognition, is used as a framework for a human-web interaction (HuWI) cycle. The HuWI cycle assumes that while users interact with a website, in order to locate certain pieces of information, they sample only goal-relevant information from the website. Users then modify their knowledge of the system, based on the goal-relevant information that was acquired. This newly modified system knowledge then directs their interaction further.
Empirical Tests of the Human-Web Interaction Cycle BIBAFull-Text 1538-1542
  Keith S. Jones; J. Shawn Farris
Farris (2003) proposed the Human-Web Interaction (HuWI) cycle, which predicts that 1) system knowledge (i.e., one's knowledge base) will direct interaction with a website, 2) system knowledge will be modified by the user's interaction with the website, and 3) only goal-relevant information should be attended to during these interactions. This paper describes two experiments that tested these three predictions. In Experiment 1, performance was worse when participants' system knowledge was inconsistent with a website, which suggests that system knowledge was directing interaction with the website. In addition, participants tested for knowledge of the content before and after interacting with the website demonstrated higher posttest scores than pretest scores, which indicates that system knowledge was modified by interacting with the website. In Experiment 2, participants attended primarily to goal-relevant information, if the goal pertained to content. These findings generally support the validity of the HuWI cycle.


Internet-Based Distance Education Materials: Does Writing Style Matter BIBAFull-Text 1543-1547
  Keith S. Jones; Peter D. Elgin; R. Johnson Brian; J. Shawn Farris
How can distance educators format materials so that they maximize usability and optimize learning? Several web-writing characteristics have been identified that address these questions. "Objective" writing, most analogous to educational text, presents information without exaggerations or boasting. "Concise" and "scannable" writing omit superfluous information and support visual scanning by highlighting key features, respectively. "Combined" writing aggregates characteristics from the objective, concise, and scannable styles. Previous research suggests that, in contrast to results from the commercial domain, these writing styles do not influence memory of distance education materials. This discrepancy is possibly due to measurement differences. To address this issue, the present study employed recognition (i.e., multiple-choice) and guided recall (i.e., fill-in-the-blank) tasks in order to assess the efficacy of the writing styles in a distance education context. The results, however, confirmed the earlier findings, i.e., regardless of the material's writing format, memory for web site content was unaffected.
Developing an Effective Section 508 Web Accessibility Compliance Program BIBAFull-Text 1548-1551
  Jesse L. Walker; Shilo H. Anders; Sarah J. Swierenga
With the adoption of Section 508 guidelines, the web community has wrestled with the issue of implementing an accessibility compliance program. This paper addresses some of those challenges that inhibit Section 508 compliance and proposes a three-prong approach. Making web pages compliant involves removing accessibility issues in the development, maintenance, and evaluation of web sites.
The Influence of Mere Exposure on Web Based Breadcrumb Navigation BIBAFull-Text 1552-1556
  Spring S. Hull; Barbara S. Chaparro; Charles G. Halcomb
Recent studies have shown that while the use of breadcrumb trails to navigate a website can be helpful, few users choose to utilize this method of navigation. This study investigates the effects of "mere exposure" and training on breadcrumb usage and satisfaction. Participants were randomly assigned to one of three conditions. Condition I participants received both exposure and instruction to use breadcrumb navigation. Condition II participants received only mere exposure to the use of breadcrumb navigation and Condition III participants received neither exposure nor instruction to use breadcrumb navigation. Upon completing a list of search tasks, Condition I participants spent less time, visited fewer web pages, and relied less on other methods of navigation. The mere exposure group, Condition II, did not produce significantly faster search times or visit fewer web pages than the participants in Condition III.
Application of Human-Computer Interaction Theories to Identify User Requirements for Internet Portal Design BIBAFull-Text 1557-1560
  Sushma Rao; Tonya L. Smith-Jackson
This paper describes the first of two parts of a research study. The overall objective of the research was to determine the effects of tailoring Internet portal content and presentation style to user requirements according to either or both of two HCI theories. This study involved user requirements gathering by using a portal containing hyperlinks as the test bed. Participants rated the hyperlinks according to importance and the descriptions of each hyperlink according to intuitiveness. Results are discussed in terms of user search behavior and specific search requirements.

MACROERGONOMICS: Macroergonomics: Analysis, Technology, and Quality of Worklife

Analysis of Tools to Manage Engineering Design Life-Cycles BIBAFull-Text 1561-1565
  Paige E. Smith; Brian M. Kleiner
This research determined how team design and project management (planning and tracking) affected design performance and the personnel working on the design. A laboratory study was conducted to evaluate three factors: team design (individuals versus groups), project support (no project support versus manual project support versus automated), and the engineering design life-cycle, which includes conceptual design, preliminary design, and detailed design. There were six observations per treatment, involving a total of 72 undergraduate engineering students. The impact of these factors were evaluated for design cycle time, cost effectiveness, mental workload, and job satisfaction. The design cycle time was 17% longer for participants without project support compared to those with automated support (p<0.05). Groups and individuals allocated their time differently during design (p<0.05). Mental workload, measured with the NASA Task Load Index (TLX), increased 16% over time (p<0.001). In addition, the combination of design phase and project tracking support affected the TLX rating (p<0.01). Job satisfaction was 5% lower at the end of the design project compared to the beginning of design (p<0.05).
Capturing Medical Documentation on the Battlefield Frontline -- A Macroergonomic Analysis BIBAFull-Text 1566-1570
  Carita A. DeVilbiss
The frontline of military health care on the battlefield poses significant challenges to medical data collection, whether collected via paper or digitization. The mobility and tempo of the frontline and the physical needs of the patients significantly impact the combat medic's ability for timely, accurate, and thorough recording of patient encounter information. In the design of new integrated management information systems, basic data capture issues must not be ignored or minimized. If data is not captured, it will not be available within the information system, regardless of whether it is a paper-based or a digital system. This macroergonomic analysis evaluated the medical data generated at the frontline as well as current and proposed data capture procedures. Another key component was an evaluation of the healthcare providers at that level of care. The results were compiled into three key design strategies relevant for the next acquisition cycle of medical data capture devices.
The Relation Between Job Characteristics and Quality of Working Life: The Role of Task Identity to Explain Gender and Job Type Differences BIBAFull-Text 1571-1575
  Peter Hoonakker; Alexandre Marian; Pascale Carayon
Women are largely underrepresented in the Information Technology (IT) workforce. Our study examines the factors related to the work environment that may contribute to the high turnover of women in the IT workforce. The literature links Quality of Working Life (QWL) to turnover intention, and turnover intention to turnover. In this study, we conducted secondary data analysis of questionnaire data collected from a sample of 1,110 employees of a single organization. We examined the impact of gender and job type (i.e. IT job versus non-IT job) on various indicators of QWL, as well as on the relationship between job factors and QWL. The results show that, specifically for women in IT jobs, task identity is highly associated with QWL.
Quality of Working Life Among Women and Men in the Information Technology Workforce BIBAFull-Text 1576-1580
  Jen Schoepke; Peter L. T. Hoonakker; Pascale Carayon
In this paper, we examine quality of working life (QWL) and evaluate and compare the predictors of QWL among 624 women and men in a variety of information technology (IT) jobs in five companies. The following QWL factors were examined: job satisfaction, fatigue, tension, organizational involvement, and burnout. The following predictors of QWL were studied: IT demands, role ambiguity, decision control, challenge and demographics (age, marital status, parental status, and education). Analysis shows that in our sample women in IT jobs do not report poorer QWL than men in IT jobs. On the contrary, women report greater organizational involvement than men.
Work Environment and Quality of Working Life Among the Cambodian Workforce: A Pilot Study BIBAFull-Text 1581-1585
  Maria J. Brunette
The first Cambodian families arrived in Lowell (Massachusetts) in the early 80s, most of them as refugees, victims of a brutal regime. Since then, the city has grown into the second largest Cambodian-American population in the U.S., behind only Long Beach, California. Cambodian workers are employed in labor-intensive jobs as well as in the service industry in the Lowell area and its surroundings. As many other immigrant groups in the U.S., they face several work and non-work related problems above and beyond their various language and culture barriers. In this paper the author presents results of a pilot study aimed at exploring Cambodian workers' perceptions of their conditions of work and the impact of such conditions in their quality of working life.

MACROERGONOMICS: Macroergonomics: Approaches and Interventions

A Combined Macroergonomics Public Health Approach to Injury Prevention: Two Years Later BIBAFull-Text 1586-1590
  Valerie J. Berg Rice; Clayton Gable
One reason for implementing a macroergonomic approach is the belief that it will yield improvements sustained over time. Between January 2000 and June 2001, an injury prevention program was implemented with U.S. Army students attending Advanced Individual Training (AIT) as Combat Medics. The highly successful original intervention included a general (2000) and a targeted (2001) program that reduced clinic visits for musculoskeletal complaints and decreased limited duty days. Two and a half years later, there is a continued decline in new profiles (limited duty assignments) among women (6.9% in 2000, 5.6% in 2001, and 3.1% per week in 2003), and slightly higher, but still low, new profiles for men (3.2% in 2000, 1.4 in 2001, and 2.5% per week in 2003). In addition, fewer soldiers are held over in AIT due to training related injuries (3% vs. < 1%). Although many factors can influence changes over time, AIT leadership and the authors believe the two most significant factors are the standard physical training program and the accountability process.
Designing a Supervisory Training Program to Optimize Injury Response: A Macroergonomics Approach BIBAFull-Text 1591-1595
  Michelle M. Robertson; William S. Shaw; Glenn Pransky
The role of supervisors to aid injured workers by accessing health care and providing reasonable accommodations has been suggested as a means to prevent prolonged disability among workers experiencing musculoskeletal pain and discomfort. Based on a macroergonomic approach, a 4-hour supervisor training workshop was designed to optimize supervisors' responses to work injuries through improved communication and accommodation. Supervisors from two industries provided high ratings of the workshop, and showed post-training improvements in injury-related attitudes and perceived ability to communicate with and accommodate injured workers effectively. Workers' compensation claims data in the 7 months before and after the workshop showed a 47% reduction in new claims and an 18% reduction in active lost-time claims versus 27% and 7% respectively, in the control group. Improving the response of frontline supervisors to employees' work-related health and safety concerns may produce sustainable reduction in injury claims and disability costs.
Two Micro IDC Field Investigations Requiring Macro Interventions BIBAFull-Text 1596-1600
  P. A. Scott; C. J. Christie; M. Renz
In industrially developing countries where there are so many minor to major problems across the broad spectrum of basic to sophisticated work sites, and where there is little knowledge of ergonomics, the very limited number of qualified Ergonomists are often 'forced' into taking a micro or macro approach to deal with the immediate problem as soon and as effectively as possible. Two recent requests for an investigation of the Human Operator-Task interaction (micro level) reiterated the clear need for a micro-macro approach in the analysis of any work site no matter what the reported problems are.
Implementing New Technology BIBAFull-Text 1601-1604
  Dennis R. Jones; Michael J. Smith
Organizations have come to rely on implementing new technology as a critical component of their competitive strategy. Implementing new technology allows companies to improve efficiency, productivity, quality, safety, working conditions, and profitability. Much of this potential is never realized; as a study found that 40% of companies had not achieved the intended benefits from the new technology. The study further stated that 10% of these new technology implementation problems were for technical reasons; whereas most problems occurred for human and organizational reasons. Effective new technology implementation requires considering all factors involved in the implementation process as: new technology characteristics, organization structure, task factors, environmental characteristics, and human factors. It is suggested to utilize a cooperative approach implementing new technology, relying on employee participation and teamwork. By taking a total systems view of the situation; and being aware to the existing interactions; it is hoped that the new technology can be implemented in the most effective way possible. A case study is presented to illustrate this.


Red Team Performance for Improved Computer Security BIBAFull-Text 1605-1609
  Sara Kraemer; Pascale Carayon; Ruth Duggan
This research attempts to develop a human factors understanding of red team assessment strategies in computer and information security. Red teaming is an advanced form of assessment that can be used to identify weaknesses in a variety of security systems. The purpose of this research is to identify and define the various dimensions of red team effectiveness with the aim of improving red team performance. A study of a red team was conducted in collaboration with Sandia National Laboratories Information Design Assurance Red Team (IDART). The design of the study included semi-structured individual interviews and focus groups with red team members and observation of red team practices. The analysis yielded various dimensions of red team effectiveness from the customer, management, individual, and team member perspectives.
Empirical Evaluation of Organizational Epidemiology in Power Plants BIBAFull-Text 1610-1614
  T. J. Ayres; M. M. Gross
This paper provides an update on an exploration of using empirically-developed equations ('models") to predict power plant performance from diverse antecedent conditions related to human performance. After covering background on the project approach and findings, recent results are discussed. Models in this second phase work were based on over 7 years of historical monthly data for operating and personnel conditions at one power plant, employing predictive lags of at least 4 months. Results were promising for several of the outcome measures studied. Strengths and limitations of the approach, and recommendations for future application, are discussed.

MACROERGONOMICS: Macroergonomics in Health Care

Conceptual Framework for Studying Shift Changes and Other Transitions in Care BIBAFull-Text 1615-1619
  Robert L. Wears; Shawna J. Perry; Eric Eisenberg; Lexa Murphy; Marc Shapiro; Christopher Beach; Pat Croskerry; Ravi Behara
In healthcare systems, division of labor and the need for continuous, 24 hour care subjects patients to multiple transitions in care. These transitions, or turnovers, are potential points of failure but have not been intensively studied. We observed care transitions in 5 EDs as part of a study on safety in emergency care and found that very different sorts of handovers occur in different settings. Based on these observations, we propose a conceptual framework for characterizing turnover events. The ability to characterize certain types of transitions may help clarify future studies and assist in crafting interventions to the context of work.
Refining the Walter Reed Sleep Management System: An Exemplar for Systems Improvement Using a Macroergonomic Approach BIBAFull-Text 1620-1624
  Nancy L. Grugle; Brian M. Kleiner; Nancy J. Wesensten; Thomas J. Balkin
Sleep deprivation, by impairing performance capacity, threatens health and safety across both civilian and military sectors. The Walter Reed Army Institute of Research (WRAIR) has developed a sleep management system (SMS) which provides a sociotechnical template for research in this area. A literature review was conducted to lay the groundwork for development of additional empirical research studies relative to sleep deprivation in order to further develop the sleep management system. Based on the existing body of knowledge regarding sleep deprivation effects on cognitive performance, and based on the ongoing development of the sleep management system, we suggest that a macroergonomic or sociotechnical systems approach to intervention may be useful in optimizing health and safety performance. This paper reviews the pertinent sleep deprivation literature and outlines the important issues for a macroergonomic research agenda.
Transitions in Care: Signovers in the Emergency Department BIBAFull-Text 1625-1628
  Robert L. Wears; Shawna J. Perry; Eric Eisenberg; Lexa Murphy; Marc Shapiro; Christopher Beach; Pat Croskerry; Ravi Behara
The need for 24-hour emergency care requires emergency department (ED) staff to work in shifts. We observed shift transitions in 5 EDs as part of a study on safety in emergency care. We found the observable characteristics of shift transitions to be highly variable across institutions and dynamically variable within shift change episodes. However, across all sites, turnovers were interactional rather than transactional, and were highly tailored to the immediate context. The high degree of situatedness in the turnovers suggest they are not likely to be adapted to a standardized tool or protocol.
Patient Safety Climate (PSC) in Outpatient Surgery Centers BIBAFull-Text 1629-1633
  Carla J. Alvarado; Pascale Carayon; Ann Schoofs Hundt
We examined perceptions of safety climate from health care professionals involved in the "Systems Engineering Intervention in Outpatient Surgery -- a Collaborative Community Perspective" study currently underway at the University of Wisconsin-Madison. Surveys were conducted in five outpatient surgery centers. The objectives of this study were to examine patient safety climate across various outpatient surgery centers and to address 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 safety climate scales (1) Top management commitment to patient safety, (2) General patent safety climate, (3) Employee commitment to patient safety, and (4) Change in patient safety can be created from the 12-item questionnaire and they may be a useful measure of an outpatient surgery center's patient safety climate. The four patient safety climate scales are also significantly associated with the outpatient surgery centers employees' QWL.

MEDICAL SYSTEMS AND REHABILITATION: Analysis and Decision Support in Medical Systems

Designing an Information Querying Interface for a Rheumatoid Arthritis Patient Record System BIBAFull-Text 1634-1637
  Alireza Edraki; Paul Milgram
Physicians need to integrate large amounts of information from patient records to determine their patients' current status. Retrieving and querying patient related information involves cognitive processes. To design an easy to use and effective querying interface for modern electronic medical records, a good understanding of the cognitive processes involved in patient related information querying is essential. In this paper cognitive work analysis (CWA) is discussed as a tool for understanding the work domain and for guiding the development of new electronic patient record interfaces, in our case for use by rheumatologists. In particular, CWA is discussed from the point of view of the abstraction hierarchy (AH) framework, and an initial AH of the patient information system work domain is presented.
The Tradeoffs and Side-Effects of Migrating from Wireless Computer to Pda-Based Support for Medication Administration BIBAFull-Text 1638-1642
  Roger J. Chapman; Michelle L. Rogers; Marta L. Render
This research involved evaluating a PDA application developed to provide a more mobile version of an existing Veterans Administration software program called BCMA (Bar Code Medication Administration). The original application was designed to be operable from a wireless desktop or laptop computer situated on a cart and connected with a bar code scanner to scan patient wristbands and medication labels. The primary goals of this system are to verify the medications about to be given to a particular patient are those ordered and to document the process. The PDA version is intended to meet the same goals utilizing a scanner built into the PDA itself, but also offer the benefits of a small, light-weight, mobile system. The evaluation involved usability inspection, usability testing, and structured interviews. The results describe (1) how the operating system's virtual keyboard display interacted with critical data in the application; (2) how the application software developers dealt with the challenge of a small screen size and the implications of those decisions; and (3) how users adapted their workflow attempting to maximize the benefits of greater mobility, while compensating for a loss in visibility.
Video-cued recall: its use in a Work Domain Analysis BIBAFull-Text 1643-1647
  Anne Miller
A Work Domain Analysis involves the context independent representation of work domain resources as a field for action. However, formal knowledge may not represent all of the resources available to workers in practice. Thus expert knowledge is essential to an accurate inventory of work domain resources. Most knowledge elicitation methods involve self-reports, which are subject to bias. This paper presents video-cued recall as a technique that may reduce bias. This technique proved useful as part of a Work Domain Analysis of the intensive care unit patient work domain.
Design and Evaluation of a Graphical Pulmonary Display for Anesthesia BIBAFull-Text 1648-1650
  Frank A. Drews; S. Blake Wachter; James Agutter
A multi-disciplinary team developed and evaluated a graphical pulmonary display to support anesthesiologist's treatment of pulmonary complications. The design process incorporated central findings from the areas of naturalistic decision-making and medical cognition, and used rapid iterative prototyping. To evaluate performance when using the pulmonary display, 19 anesthesiologists participated in a study in a high fidelity simulator. 10 subjects used the graphical pulmonary display; 9 received the same information presented numerically. The anesthesiologists treated five critical events and one "non-event". Measurements were taken for effective treatment time. The pulmonary display tended to improve overall performance. In addition, we found effects of expertise, with experts treating faster than the two less experienced groups.
Clinical Reminders: Why don't they use them BIBAFull-Text 1651-1655
  Laura Militello; Emily S. Patterson; Toni Tripp-Reimer; Steven M. Asch; Constance H. Fung; Peter Glassman; Shilo Anders; Bradley Doebbeling
There are many potential benefits associated with the use of computerized clinical reminders for both health care providers and patients. Clinical reminders are designed to reduce the likelihood that an aspect of care will "fall though the cracks" during a busy exam, ensure that care is well-documented so that the range of health care providers interacting with each patient will have full access to the patient history, and increase standardization across patient exams. While most agree that the concept of clinical reminders is good, recent research indicates that some providers do not use clinical reminders when available (Demakis et al, 2000). This paper describes the qualitative portion of a survey study aimed at exploring the perceived facilitators and barriers to clinical reminder use within Veterans Administration health care facilities.

MEDICAL SYSTEMS AND REHABILITATION: Human Factors and Safety in Medical Systems: Where Have We Reached? Where Should We Go?

Human Factors and Safety in Medical Systems: Where have we reached Where should we go BIBAFull-Text 1656-1660
  Daniel Gopher; Yoel Donchin; Richard Cook; Jane Fulton; Penny Sanderson
Over the last two decades there has been a growing recognition in the need for a systematic study of adverse events, errors and difficulties in health care. The systematic investigation of this topic and the resultant database have grown and diversified exponentially. We believe that the time has come to evaluate the achievements of this first wave of research, and discuss directions for the next stage. The participants in the panel have been major contributors to this area of work. They differ in their background and specific research interests, which reflect aspects of the overall medical system. The panel addresses several key questions: Merit of different information sources, retrospective versus prospective studies, implementation methods, and education needs. The discussion examines commonalities and differences of philosophy, principles and approaches, with an eye on guiding future work.

MEDICAL SYSTEMS AND REHABILITATION: Medical Systems and Rehabilitation

Laparoscopic Surgery: Are Multiple Viewing Perspectives better than One BIBAFull-Text 1661-1664
  Patricia R. DeLucia; Melody L. Hoskins; John A. Griswold
Imaging systems are used increasingly in surgical procedures such as laparoscopy. Depth perception is degraded compared with open surgery because the image provided by a laparoscopic camera is two-dimensional and represents a single viewing perspective. One way to compensate for this loss of depth information is with multiple cameras, each providing a different perspective. We measured performance of a pick-and-place task when observers viewed the task environment with three cameras concurrently (top, front, side views) or with one camera. Performance was slower with camera viewing compared with direct viewing and slowest with the side view. Although concurrent presentation of three camera views did not improve performance, observers looked almost exclusively at one of these views (top). Future research should determine whether observers can be trained to use depth information provided by multiple cameras. It is important to determine how to configure imaging systems so that surgical procedures can be optimized.
Designing an Overview Display for Computer Supported Medication Administration to Reveal Hidden Dangers to Patient Safety BIBAFull-Text 1665-1669
  Roger J. Chapman; Russell A. Carlson
The Veterans Health Administration uses a software application called Bar Code Medication Administration (BCMA) to assist in medication administration. The wireless application is typically operated on a desktop or laptop computer, physically located on a mobile cart during med passes. It works with a handheld bar code reader to scan patient wristbands and their medications to verify a match between the patient identified and the medications scheduled at the time of the scanning. Since replacing the paper-based system with this technology the rate of medication errors has declined significantly. After a participatory design process developing an overview display for BCMA, it was concluded such an additional view on the patient and medication data has promising safety and efficiency benefits by (1) integrating the current med pass view with a broader summary of medications active in +/- 24 hours and the patient's condition, so that relationships can more easily be seen; and a natural direct manipulation mechanism to zoom in for more details would be provided; (2) including a picture of the patient as an additional form of identification; (3) supporting perceptual and mechanical filtering to separate medications by attributes (e.g. time due and status) and facilitate efficient situation awareness and prioritization of actions; (4) including status information for medication orders in other nurses' med passes so they can more easily collaborate; (5) for each medication showing both the last action and next action, so that status information can be used to maintain awareness of what has happened and is going to happen from a medication perspective.
Designing Simulation-Based Training Scenarios for Emergency Medical First Responders BIBAFull-Text 1670-1674
  Fuji Lai; Eileen Entin; Meghan Dierks; Daniel Raemer; Robert Simon
Simulation-based training is a promising instructional approach for training military and civilian medical first responders such as EMTs. There is a need for first responder training in cognitively-based skills such as situation assessment and decision making. We are developing a training program for first responders that uses mannequin-based simulation technology effectively to fill this training need for valid meaningful scenarios that can be integrated into the curriculum and applicable for a variety of EMT skill levels. The program will provide detailed scenarios, instructions for administering the program, and measures for performance feedback. Each scenario will exercise a combination of skills and the set of scenarios will span all of the higher-level skills that have been identified as benefiting from targeted training. We discuss here the iterative process of designing and developing the first of these scenarios which has been shown to be capable of tapping into and measuring different skill levels.
Evaluation of Physical Versus Virtual Surgical Training Simulators BIBAFull-Text 1675-1679
  S. L. Waxberg; K. H. Goodell; D. V. Avgerinos; S. D. Schwaitzberg; C. G. L. Cao
With the recent attention on patient safety, there is an increased interest in standardized training for laparoscopic surgeons. Studies have shown that laparoscopic simulators can be used to train surgical skills. A comparison of two popular systems (a real physical model and a virtual model) was conducted to determine the relative effectiveness of the systems for training purposes. Twenty-two medical students and surgical residents were tested on both simulators. Time to task completion and errors committed were recorded and compared. Our results showed that the physical training system was more sensitive to the experience levels of the subjects than the virtual system, and may be more effective as a tool for standardized training. However, as virtual reality technology becomes better developed, and surgeons become more familiar with the technology, we may see a change.
Applying Human Factors Research on Warnings to a Decision Support for Primary Care Physicians BIBAFull-Text 1680-1684
  Geva Vashitz; Joachim Meyer; Avi Porath; Julian Zelingher; Dan Y. Bonneh; Yaakov Henkin; Maximo Maislos; Roni Peleg; Harel Gilutz
Human Factors research on warning systems may have relevance beyond the specific domain of operators receiving warnings about potential problems in technological systems. We present an analysis of physicians' responses to letters generated by an automated decision support system in terms of findings in the human factors literature on warnings. The automated system mails reminders to primary medical teams about patients requiring screening or lipid-lowering drugs. The effectiveness of the system depends, among other factors, on physicians' responses to the reminders. Some properties of the reminder letter have parallels in warning systems. They should affect physicians' responses as they affect the responses of operators of technological systems. We report the results of preliminary analyses of data after a 16 months follow-up of 6,571 patients. The compliance rate to recommendations in the letters in the intervention group, in which physicians receive reminder letters, was significantly higher than in the control group. Physicians in the control group were found to be less compliant as the number of their patients requiring the medical care grows. In contrast, physicians in the intervention group, who received the reminder letters, maintained similar levels of compliance irrespective of the number of patients who required their care. Thus the letters appear to provide valuable information for physicians who have to cope with more difficult patient populations.

MEDICAL SYSTEMS AND REHABILITATION: Migration of Medical Devices from Clinical to Home Care

Human Factors Considerations in the Migration of Medical Devices from Clinical to Homecare Settings BIBAFull-Text 1685-1689
  Melanie J. Turieo; Marlene A. Devine; Rodney Hasler; San Diego; Ronald Kaye; Wendy A. Rogers
To accommodate the increased number of patients receiving care at home, more and more medical devices are being taken out of the controlled clinical setting and are being used by lay caregivers in a home environment, thereby posing risks for misuse, malfunction and error. It has therefore become critical to examine the environment of medical devices being used in the home and to ensure that products intended for home healthcare use are being designed so that lay users can learn, operate, and maintain them with greater safety, satisfaction, accuracy, and comfort. This panel brings together representatives of four stakeholder groups associated with this issue -- regulatory agencies, human factors professionals, the user population, and medical device developers. Panelist presentations and the ensuing discussion will focus on the concerns, issues, problems, and/or liabilities associated with medical devices migrating into the home, from each of these groups' perspectives.

MEDICAL SYSTEMS AND REHABILITATION: Performance Issues in Medical Applications

Comparison of Torso Movements in Manual Transfer Tasks: Influence of Spinal Cord Injury and Low Back Pain BIBAFull-Text 1690-1694
  K. Han Kim; Su Bang Choe; Bernard J. Martin
The purpose of this study was to characterize functional limitation in seated manual transfer tasks for low back pain (LBP), spinal cord injury (SCI), and control subjects. Seated subjects performed either two- or one-handed transfer tasks to one of three targets 87cm above the hip-point at 0, 45, and 90° azimuths. Three torso angles (flexion, lateral bending, and axial rotation) were obtained from captured motions and modeled by combinations of B-spline base functions. The results demonstrated that 1) the SCI and LBP subjects exhibit smaller torso flexion than controls; 2) the SCI subjects tend to move the torso (lateral bending and extension) away from the target; and 3) these group differences are reduced in one-handed transfers and light load conditions. The movement patterns suggest that SCI patients may have adapted strategies to compensate for the limited control of upper body balance, while LBPs may limit torso motion to avoid pain.
Effects of Viewing Angle, Spatial Ability, and Sight of own Hand on Accuracy of Movements Performed under Simulated Laparoscopic Conditions BIBAFull-Text 1695-1699
  Madeleine Keehner; Diana Wong; Frank Tendick
We examined performance on a maze-drawing task under conditions designed to simulate hand-assisted laparoscopy (a form of minimally invasive surgery in which the surgeon's non-dominant hand is inserted into the patient's abdominal cavity through an enlarged incision). The task was completed without direct vision, with participants relying solely on the image from a laparoscopic camera to guide their movements. On half the trials, participants held their non-dominant hand in view of the camera. We varied camera angle (offset in azimuth by 0°, 90°, 180°, or 270°), and measured spatial visualization ability. Both camera angle and spatial ability affected overall performance, and these two factors interacted. At 90°, having the hand in view significantly improved performance for all participants, but at 270° it impaired low spatial participants. At 0°, 90°, and 180°, the performance of high and low spatial participants differed significantly only when the hand was in view. Correlations supported the interpretation that hand-in-view accentuated, rather than attenuated, the relationship between spatial ability and performance. The findings have potential implications for surgeons using hand-assisted laparoscopic techniques in minimally invasive procedures.
The Multi-Dimensional Nature of Stress in an Endoscopic Surgery Simulator BIBAFull-Text 1700-1703
  Martina I. Klein; Joel S. Warm; Michael A. Riley; Gerald Matthews; Kelley S. Parsons
Endoscopic surgery offers substantial advantages over traditional open surgery, but endoscopic techniques require considerable practice and have been reported to induce high levels of stress in the surgeon. Some of that stress is believed to arise because of perceptual-motor distortions associated with the endoscopic interface. Prominent among those distortions is the disruption of normal eye-hand mapping in the endoscopic environment. The present study used the Dundee Stress State Questionnaire to determine the stress profile associated with performance in a simple endoscopic simulator under varying degrees of distortion of eye-hand mapping. The results indicated distinct stress profiles associated with different levels of hand-eye mapping distortion.
Effects of Friction on Haptic Perception in Simulated Endoscopic Environments BIBAFull-Text 1704-1707
  J. Perreault; C. G. L. Cao
Current endoscopic instrumentation cannot replicate the haptic feedback available during open surgery. Distracting friction forces in the interface make it difficult for surgeons to detect and differentiate between small-scale surgical site forces. As a result, the visual channel is being used to process information that should be available through the haptic sense. An experiment was conducted to examine the effects of friction, when probing tissues of dissimilar compliance. Results showed that the presence of friction in the interface increased applied force by 45°, contact time by 40°, and errors by a factor of 2 (100°), while its absence increased human operator confidence by 15°. The effects of friction were generally more pronounced in conditions with impaired visual cues but were also very strong when vision was available. These results are applicable to the design of more effective instrumentation for endoscopic surgery as well as robotic surgery.
Challenges with the Performance of Failure Mode and Effects Analysis in Healthcare Organizations: An Iv Medication Administration Hfmea BIBAFull-Text 1708-1712
  Tosha B. Wetterneck; Kathleen Skibinski; Mark Schroederx; Tanita L. Roberts; Pascale Carayon
The value of performing prospective analysis before technology implementation is well known to the chemical, nuclear and aviation industries. The performance of a failure mode and effects analysis (FMEA) is now required by healthcare organizations accredited by JCAHO as part of their patient safety standards. However, most healthcare organizations have little experience with applying human factors engineering techniques to process or technology evaluation and the procedure of how and when healthcare organizations should perform FMEA is not well described. This paper describes the method and challenges of performing a process and design FMEA to prepare for the implementation of a new intravenous infusion pump at a University Hospital. Recommendations are made for the performance of a process and design FMEA for new technology implementation in healthcare organizations.


Optimizing the Surgeon-Robot Interface: The Effect of Control-Display Gain and Zoom Level on Movement Time BIBAFull-Text 1713-1717
  R. Darin Ellis; Alex Cao; Abhilash Pandya; Anthony Composto; Mathew Chacko; Michael Klein; Greg Auner
While many advances have been made in surgical robotics technology, even for surgeons with relatively high levels of robotic surgery experience, many tasks take less time to perform manually. Although there are other benefits to surgical robotics that may outweigh task completion time, relatively lower efficiency will hinder the adoption of this technology. This study focused on two interface parameters: Control-Display Gain (CDG, i.e., the amount of robot movement resulting from a given robot controller movement) and the optical Zoom level that defines the working field of view. Results from a study with 10 participants suggest that CDG is a promising interface parameter for optimizing movement time in robot-assisted surgical tasks. The results have implications for the development and implementation of intelligent surgeon-robot interface technology and hold the potential to greatly improve the efficiency of robotic-assisted surgery techniques.
An Analysis of Home and Hospital Medical Device Incidents in the Maude Database BIBAFull-Text 1718-1722
  Ibraheem S. Al-Tarawneh; Walter J. Stevens; Steven R. Arndt
A review of the U.S. Food and Drug Administration's Manufacturer and User Facility Device Experience Database (MAUDE) was performed to identify medical device incident trends relating to the type of device involved, incident location, injury severity, the nature and/or cause of the event, and human factors issues involved. A total of 317,931 medical device incident reports submitted by manufacturers between the years 1997 and 2002 were reviewed. The analysis revealed that 203,021 (64%) of these reports did not contain useful event location information. Of the remaining reports, 102,303 (89%) incidents occurred in hospitals, 6,153 (5%) incidents occurred in outpatient treatment facilities, 2,511 (2%) incidents occurred in ambulatory surgical facilities, and 3,157 (3%) incidents occurred at home. The majority of the incidents that occurred at home involved blood glucose meters (42%), defibrillators (10%), ventilators (8%), and wheelchairs (5%). Home incidents resulted in 108 fatalities and 776 injuries. The majority of the fatalities were associated with defibrillators (32%), ventilators (19%), oximeters (8%), and hemodialysis devices (6%). Seven of the 21 fatal home ventilator-related incidents were attributed to low, delayed, or non-sounding alarms. Hospital incidents comprised 102,303 records, with 2,046 incidents resulting in fatalities. A large share of the fatal hospital incidents were related to defibrillators (11%), catheters (11%), heart valves (10%), pacemakers (5%), and ventilators (4%). Six fatal hospital ventilator-related incidents were attributed in part to delayed, silenced, or non-sounding alarms.
Design of a Vesitbular Examination and Treatment Device BIBAFull-Text 1723-1726
  Brock Miller; Ron Wardell; Beth Lange
To diagnose and treat vestibular disorders, physicians presently manipulate the patient's head and neck, or whole body, through prescribed maneuvers. This project developed a device to aid physicians in such maneuvers while accommodating back and neck pain sufferers. An investigation was conducted into the physiological and mechanical properties of the vestibular system and into the current medical procedures through literature review, observational task analysis, and other analyses. The problems faced by practitioners when engaging patients with current practices and medical devices were identified and a set of recommendations and design implications were created. In questioning the medical procedure, a theory was developed to provide diagnosis and treatment in a more innovative and effective manner. The project considers human factors, safety, functionality and the needs of both doctors and patients.
The use of Structured Interviews in the Evaluation of a Teledermatology System BIBAFull-Text 1727-1731
  Aideen J. Stronge; Timothy A. Nichols; Wendy A. Rogers; Arthur D. Fisk; Jeanette D. Rasche; Angela Dingbaum
Telemedicine systems have been found to increase access to patient care and decrease healthcare costs. However, the widespread adoption and use of telemedicine technologies has been low. The purpose of the present study was to evaluate an existing store-and-forward teledermatology system used by the U.S. military. The human factors issues that emerge in the evaluation of a telemedicine system include user characteristics (e.g., motivation to use the telemedicine system), macro-organizational issues (e.g., workload distribution, communication between team members), and technology issues (e.g., comfort using digital cameras or the World Wide Web). Users of the teledermatology system completed a questionnaire and an interview session. The detailed data from the structured interviews provided insight into the nature of these macro-organizational, user characteristics, and technology issues. The goal of this project was to illustrate how human factors methods can be used to understand the factors that contribute to the success or failure of this system, identify issues/potential problems, and provide recommendations for the current system and guidance for the design of future systems.
How to Improve Working Conditions for Spinal Cord Injured An Intervention Study at the Workplace BIBAFull-Text 1732-1735
  Leif Sandsjo; Lena Grundell; Kirsi Valtonen; Ann-Katrin Karlsson; Eira Viikari-juntura
In this study the working conditions of six spinal cord injured (SCI) and one meningomyelocele (MMC) subject were evaluated with regard to risk factors for neck and shoulder disorders. Each subject was visited by an ergonomist at the workplace where the working conditions were documented by means of video recordings, questionnaires and the ergonomist's evaluation of the workplace. From situations identified, including the subject's own reporting of problematic situations and layout of the workplace, possible changes were discussed and implemented if feasible.
   A specific aim of the study was to see if a myofeedback method to be used during work at the regular workplace was applicable and of use to promote a more favourable activation of the neck- and shoulder muscles in this group of subjects.
   The experiences from this study are that the employer had usually not optimised the participating subjects' workplaces and that several easily implemented changes could be made that improved the working conditions. Regarding the myofeedback intervention, all of the subjects taking part increased the amount of time where the trapezius muscle was in a rest-like condition, which should be considered a change in a positive direction.
Assessing People's Knowledge and Beliefs About Dietary Supplements BIBAFull-Text 1736-1740
  Michael J. Kalsher; Michael S. Wogalter; Kenneth R. Laughery
Many Americans have turned to dietary supplements for help in losing weight despite the significant health risks associated with their use. This study examines what people know and believe about dietary supplements. Results showed that participants were generally knowledgeable about dietary supplements, including their purpose, where they are sold, and the possibility that some dietary supplements can have unhealthy side effects. However, participants' knowledge and beliefs differed significantly as a function of gender, educational status, and whether they had ever taken dietary supplements. Users tended to perceive dietary supplements as less risky than participants who had never used them. Both male and student participants held more optimistic perceptions about the expected benefits and risks of dietary supplements, but were less likely to read the labels on these products. These results indicate that individual differences need to be taken into account when developing risk communications to accompany dietary supplements. Future research should address how knowledge gaps about dietary supplements can be addressed by educational and warning materials to influence knowledge and beliefs with the goal of providing needed information to make informed healthful decisions.
Integrating Task Analysis in Software Usability Evaluation: A Case Study BIBAFull-Text 1741-1745
  Zhihua Tang; Jiajie Zhang; Todd R. Johnson; Elmer Bernstam; Douglas Tindall
This paper describes a task analysis approach to usability engineering a digital Emergency Medical Services system. In a hierarchical task analysis, we decomposed user's workflow into major tasks and examined the compatibility between software functionality and user's work process. In a cognitive task analysis, we built an expanded GOMS model to account for user interaction at the procedural level. The analyses revealed that the system's physical setup made it difficult to be integrated into user's primary patient care tasks and that the interface design put high demand on users' information processing resources at both the cognitive and perceptual-motor levels. These results complemented our previous work of heuristic evaluation of the same system but allowed us to examine software usability issues in a broader context as well as at a more fundamental level. The expanded GOMS analysis technique we introduced here is also useful in the revision of the software's user interface.

MEDICAL SYSTEMS AND REHABILITATION: Psychological and Physical Issues in the Clinical Environment

Using Psychological Scaling Techniques to Assess Clinical Expertise in Anesthesiology BIBAFull-Text 1746-1750
  Olena Connor; Matthew B. Weinger; Nancy J. Cooke; Jason Slagle
This study used Pathfinder, a psychological scaling technique, to assess underlying cognitive structure associated with mastery of relevant knowledge necessary for anesthesiology decision-making. Our study revealed this approach to be a valid method to assess the tacit knowledge that underlies clinical expertise. A set of concepts associated with a decision-to-extubate scenario was derived from expert interviews. Participants included nine attending anesthesiologists, seven first-year anesthesiology residents, and eight second-year anesthesiology residents. Pathfinder was applied to participants' pairwise relatedness judgments of the clinical concepts in the context of the scenario. Experts' data were aggregated to form an expert referent structure. Student anesthesiologists were assessed based on comparison of their structures to this referent. These comparisons yielded a knowledge score that was highly correlated with residents' exam grades. This finding supports our position that Pathfinder is a valid knowledge assessment method and, as a complement to current exams, can be applied to assess a student's deep understanding of anesthesiology concepts.
Divided Attention in using Robotic Surgical Systems BIBAFull-Text 1751-1754
  J. L. Webster; C. G. L. Cao
Current surgical robots require surgeons to divide their attention between performing the surgery and driving the robot. Our goal was to examine how this division of attention, as imposed by the new technology, affects the surgeon's performance and memory. We expected that combining the various sources of attentional demands on the robotic console would lead to better performance. Twelve subjects were tested using three interface designs: 1) LCD menu separated from operative site, 2) menu overlay on the operative site, and 3) voice control. Results showed that voice control was the fastest in delivering a command to the robot. Error rates and confidence levels were not significantly affected by the interfaces. This research has implications for designing future surgical robots to enhance the efficiency and safety of surgical procedures.
Measuring Awkwardness of Workplace Layout: Dispersion of Attentional and Psychomotor Resources within the Anesthesia Workspace BIBAFull-Text 1755-1758
  Christopher Goodrich; Julie Mills; F. Jacob Seagull; Russ Ward; Yan Xiao
In complex tasks such as provision of anesthesia, human operators often carry out simultaneous tasks with conflicting task demands. Workplace design can mitigate the impact of these tasks' conflict with one another, however there are few methodologies for quantifying awkward workplace layout that lead to task conflicts. The current work examines a measure of awkwardness we developed, "dispersion of attentional resources," and further presents a graphical display to represent task conflicts within the anesthesia work domain. These measures and display methods can be generalized to other work domains to guide design.
Safety Climate in Healthcare: A Review of Measurement Instruments BIBAFull-Text 1759-1763
  Calvin Burns; Rhona Flin; Kathryn Mearns; Steven Yule
A deficient safety culture has been implicated in industrial accidents. More recently, patient safety problems in hospital care have revealed a weak safety culture as a causal factor. As in the other industrial sectors, the level of safety for hospital patients and staff is likely to be determined largely by the hospital's safety culture.
   Measuring safety culture is a risk management technique widely used in high-reliability industries to identify safety problems before they become realised as accidents and near misses. The most common approach to measuring safety culture is to conduct a safety climate survey of the workforce. A safety climate survey typically assesses the workforce's attitudes and perceptions about work pressure, communication, reporting and safety systems, and supervision and management commitment to safety. Thus, safety climate surveys provide a range of leading indicators about an organisation's underlying safety culture, which need to be understood when designing and implementing safety interventions such as critical incident reporting systems. This paper reviews the construct validity of 13 instruments that have been used to assess safety climate in healthcare. An explanatory model linking safety climate and safety behaviours is proposed in order to develop more valid measures of safety climate in healthcare.

MEDICAL SYSTEMS AND REHABILITATION: Role of Human Factors in Health Care 2020

Panel: The Role of Human Factors in Healthcare 2020 BIBAFull-Text 1764-1767
  Carla J. Alvarado; Caroline Cao; Gary Klein; Matthew B. Weinger; Emily Patterson; Richard I. Cook; Pascale Carayon
What role will human factors professionals play in healthcare 2020? Health systems throughout the world face a number of common pressures, related to demography, epidemiology, science and technology developments, and medical demand. In particular, while developments in technology do not just provide health care with new possibilities for human factors engineering, medical interventions and therapies. They also produce changes the in our understanding of sickness and health, the possibilities and needs for managing the systems, for innovation, for standardization, and the political and economic relationships. The health care providers not only have to cope with these technological developments but assure their successful implementation and acceptance. The uncertainties and expectations linked to these innovations face major issues within the research and health care system, such as policies for managing scarcity of resources and changes in the relative frequency of diseases because of factors like ageing, and mobile global population and the like. A panel of both healthcare and human factors experts will discuss the role that human factors will play in healthcare in 2020.

MEDICAL SYSTEMS AND REHABILITATION: Usability and Assistive Technology in Health Care

Defibrillator Usability Study Among Paramedics BIBAFull-Text 1768-1772
  Rollin J. Fairbanks; Manish N. Shah; Stanley Caplan; Aaron Marks; Paul Bishop
A usability test was conducted of two different manual defibrillators regularly used in the prehospital setting by emergency medical personnel. The purpose of the study was to demonstrate that design attention is needed to make manual defibrillators more error resistant and less hazardous to patient safety. Fourteen paramedics performed four tasks in a "laboratory" environment that included a computerized Laerdal SimMan patient simulator. Even without environmental factors and the urgency of actual life-saving situations, more than twenty user interaction problems were found. Ten of the more prominent or consistent problems found are discussed here, and a design solution is proposed for each problem.
A User-Centered Evaluation of Three Intravenous Infusion Pumps BIBAFull-Text 1773-1777
  Roger Gagnon; Jason Laberge; Allison Lamsdale; Jonathan Histon; Carl Hudson; Jan Davies; Jeff Caird
Considerable research has focused on whether medical equipment can be made safer/more effective using user-centered design principles. Medication errors may result from improper operation, mechanical failure, and tampering. The present study evaluated the effectiveness and advantages of three intravenous infusion pumps. Five evaluators used heuristic evaluation to identify, categorize, and prioritize usability problems. Positive and negative features were classified according to usability and design principles. The most common negative feature was difficulty setting up an infusion. The most common positive feature was visual feedback regarding pump status. The methodology was effective at identifying a number of problems. Ongoing research involves testing domain-experts to validate the severity of the usability problems identified and discover other safety-relevant errors.
Problems with Medical Instrumentation Experienced by Patients with Disabilities BIBAFull-Text 1778-1782
  Jill M. W. Winters; Molly Follette Story; Kris Barnekow; Brenda Premo; June Isaacson Kailes; Erin Schwier; David Rempel; Jack M. Winters
Methods employed to conduct a national survey designed to identify some of the difficulties that people with disabilities have experienced as patients using medical instrumentation for healthcare are described, and results from the survey are presented. A Delphi study was conducted to refine the questionnaire, which was then distributed nationally, primarily via the Internet. The initial respondent pool was not representative of the racial, ethnic, age, and disability distribution of the population and data gathering is ongoing. Preliminary results are that a majority of respondents reported moderate to extreme difficulty with a range of common medical equipment and furniture, such as examination tables and weight scales. Subsequent studies will evaluate the identified problems in greater depth.
Physician Responses to Handheld Presentation of Clinical Evidence: Analysis of Group Differences BIBAFull-Text 1783-1787
  Danielle M. Lottridge; Mark H. Chignell; Sharon E. Straus
The Evidence at the Point of Care (EPoCare) project (Takeshita, Davis, Straus, 2002) is examining how to put clinical evidence on mobile devices to meet physicians' information needs at the point of care. Forty-seven physicians, including family physicians, general internists and medical residents, participated in usability testing with prototypes implemented on two different form factors (a tablet-style PC and a PDA-style handheld). During the testing physicians were asked to describe their impression of the prototype and to indicate their agreement with 20 statements concerning the prototype implementations. The three user groups differed in how they valued device portability and screen size. Family physicians wanted larger screen size and were less concerned with portability, while internists wanted portability and were less concerned with screen size. Residents wanted both portability and large screen size. Cluster analysis was used to identify four clusters of physicians, varying by age, amount of time in clinical practice, and frequency of use of search engines and medical databases. Differences in preferences about format of information were present amongst these clusters. This study demonstrates how large sample usability testing can be used to develop customization strategies for mobile applications, for designing both form factor and content.
Emg Evaluation of a Bed Assistive Device for Patients BIBAFull-Text 1788-1792
  Kari Babski-Reeves; Grace Tran
Limited research is available in understanding or evaluating the physical benefits of self-transfer devices for patients following major surgery. The objective of this study was to quantify muscle activity while using an assistive device during bed-rise exercises. Twenty participants (9 males, 11 females) participated. A laboratory study using a repeated measures design was used to test the effects of bed rise condition (manual, assisted), device (ABNOSTRAIN, Bed Pull-Up), device anchor height (7", 13" above bed surface), and head elevation angle (0°, 30°) on mean and peak muscle activity of the upper and lower rectus abdominus and external oblique. Results indicated that the use of a device significantly reduced muscle activity at all three muscle sites evaluated compared to unassisted bed rising. Also, having a higher anchor height or bed elevation angle further significantly reduced muscle activity.


Performance of 2D versus 3D Topographic Representations for Different Task Types BIBAFull-Text 1793-1797
  Debra MacIvor Savage; Eric N. Wiebe; Hugh A. Devine
In this study, a performance comparison is made between 2D and 3D topographic representations for solving different tasks. The tasks involved answering questions that either did or did not require elevation information and were either focused or integrative. Integrative questions required understanding the relationship of three separate locations. 2D representations (i.e., contour maps) only showed a clear advantage for focused, non-elevation questions with 3D representations not showing a clear advantage for any other task condition. There were interactions between task type, dimensionality and elevation. In addition, the integrative, elevation questions were clearly more difficult regardless of dimension. In addition, participants' visualization ability, as measured by a paper-folding test, correlated with their task performance. Further work is proposed to look at how experience interacts with these tasks and topographic representations.
The Span of Visual Processing in Tactical Displays BIBAFull-Text 1798-1802
  Jocelyn Keillor; Ipsa Desai; J. G. Hollands; Eyal M. Reingold
Visual span, or the region of the visual field from which information is extracted during a fixation, may vary as a function display complexity. As display technology evolves, military tactical displays show increasing quantities of information, often across large areas. To quantify the breadth with which an operator may process information presented in a tactical display, we related search performance to the amount of the display processed without an eye movement. The derived visual span measure was used to test the possibility that task requirements have an impact on the spatial extent of "at a glance" processing. We compared visual span on searches based on threat affiliation (color) to those based on a combination of threat affiliation and heading (color and orientation) for two naval tactical symbol sets. We found that the task an operator engaged in while searching a complex tactical display affected the portion of the display that was processed "at a glance".
Advantage for Visual Momentum Not Based on Preview BIBAFull-Text 1803-1807
  J. G. Hollands; Nada J. Pavlovic; Yukari Enomoto; Haiying Jiang
Previous research has indicated that smooth rotation of geographic terrain between two- and three-dimensional (2D and 3D) views aids task switching. However, the time taken to show the smooth rotation may also provide a terrain preview for a post-rotation judgment. To test this possibility, we examined a situation where preview was provided but smooth transition violated. Twenty-four participants made judgments about the properties of two points placed on 2D or 3D displays of terrain. Participants performed the tasks in pairs of trials, switching tasks and displays between trials. In the continuous transition condition, the display rotated in depth and in azimuth from one display format to the other. In the discrete transition condition, the azimuth rotation was in the opposite direction, and then the terrain "snapped" to the final orientation. The results showed that response time after transition was less for the continuous condition. We argue that smooth transition to the correct position provided improved visual momentum between displays.
From Specific Information Extraction to Inferences: A Hierarchical Framework of Graph Comprehension BIBAFull-Text 1808-1812
  Raj M. Ratwani; J. Gregory Trafton; Deborah A. Boehm-Davis
We examined how graph readers extracted specific information, integrated information and made inferences from choropleth graphs. We present a hierarchical framework of graph comprehension suggesting how graph readers extract these different types of information. Our framework suggests the cognitive operations required to extract these different types of information build in a hierarchical fashion as the complexity of the type of extraction increases. Empirical data gathered in our laboratory is reviewed in support of our hierarchical framework and implications are discussed.
Signal Detection Theory Applied to Size Constancy in Virtual Environments BIBAFull-Text 1813-1817
  Kimberly R. Raddatz; John Uhlarik; Jodi E. Foura
Pictorial depth cues and instructional set are two factors that influence the degree to which size constancy maintains in static two-dimensional perspective displays. Signal detection theory (SDT) allows the determination of whether these factors influence observers' sensitivity to perceived size (d') versus their subjective criteria (bias) for making "same" or "different" discriminative responses. Two objects were presented at various perceived distances in static perspective displays that varied in number of available pictorial depth cues. Observers made comparative size judgments regarding the objects' apparent distal size (phenomenal instructions) or objective distal size (objective instructions). Observers showed greater sensitivity to distal size differences when responding to apparent, rather than objective size differences. The presence of more pictorial depth cues produced greater sensitivity than a reduced-cue condition, especially under objective instructions. Overall, results indicate that SDT reveals aspects of size perception in pictorial displays not assessed through more traditional analyses based solely on accuracy.

PERCEPTION AND PERFORMANCE: Auditory Displays and Sonification

Designing Sonification for Effective Attentional Control in Complex Work Domains BIBAFull-Text 1818-1822
  Janet Anderson; Penelope Sanderson
Complex safety-critical work domains such as anesthesia require human operators to direct their attention appropriately. A sonification is a possible method for directing attention to relevant changes while still allowing monitoring under divided attention conditions. However, there is currently little information to guide the design of sonification. Two experiments investigated the effect of the number of auditory streams on ability to detect changes (Experiment 1), and the effect of the number of auditory streams under different attention conditions (Experiment 2). When monitoring with selective attention, participants noted changes more accurately with three streams than with one or two streams, but when there were also distracter changes participants noted changes more accurately in multiple streams. Overall, accuracy was lower when attention was divided than when it was selective, but accuracy was especially low in the three-stream configuration. Distracter changes increased divided attention accuracy. The results suggest that the number of streams should be minimized if operators' attention will be divided between monitoring and other tasks.
Does the Perceived Urgency of Auditory Signals Affect Auditory Spatial Cueing in Visual Search Tasks BIBAFull-Text 1823-1827
  Daniel Reed; Thomas Z. Strybel
In the auditory warning literature, investigators have identified acoustic parameters such as harmonicity and interpulse interval that affect perceived urgency of a warning sound. In the present investigation, we asked whether these parameters would affect visual orienting in a visual search task. Participants located and identified visual targets in a large cluttered search field. Audio cues to the target were also presented. In baseline conditions, auditory cues varying in perceived urgency were presented alone, and the time required to identify the visual target was measured. In the paired-cue conditions, two audio cues were presented, one valid and one invalid. Cue informativeness and cue urgency were manipulated. Performance interference was measured as the difference in search latencies between the informative cue and the corresponding cue in the baseline condition. Although baseline search latencies were not affected by perceived urgency in the baseline conditions, perceived urgency did affect the amount of interference produced by uninformative cues in the paired-cued conditions.
Effects of Training and Auditory Context on Performance of a Point Estimation Sonification Task BIBAFull-Text 1828-1831
  Daniel R. Smith; Bruce N. Walker
Research on auditory graphs has investigated mappings, scalings, and polarities (Walker, 2002), as well as the addition of some contextual design features (Bonebright, Nees, Connerley, & McCain, 2001; Flowers, Buhman, & Turnage, 1997), in order to improve performance. However, little has been done to quantify the performance effects of such features, or to investigate effects of training in specific sonification tasks such as point estimation. Smith and Walker (2002) took a step towards quantifying and comparing the effects of adding several contextual design features. Presented here are selected results from a comprehensive follow-on study comparing effects of adding auditory context, either with or without training. The overall results indicate that some kinds of auditory context improved performance, while others did not. Training improved performance, and an interaction was discovered between type of auditory context and type of training (Smith, 2003). Implications are discussed.
The Effect of Combining Monaural Cues to Distance BIBAFull-Text 1832-1835
  Skye Lee Pazuchanics
The degree to which distance can be perceived depends on combinations of distance cues that are inherently ambiguous in isolation. Previous research on combining distance cues has focused on static monocular cues and has shown an additive relation. The present experiment was designed to examine how people integrate monaural cues (loudness, delay of reception from initiation, and frequency attenuation) to perceive distance. Monaural distance information was presented to participants using desktop computers and headphones. A general linear model (GLM) analysis revealed that monaural cues, much like visual cues, are combined linearly to form a percept of distance, but with greater weighting given to loudness. Thus, designers of spatial displays that might be used in conditions of poor visibility could supply auditory cues for distance information. Additionally, this paper could be seen as a step along the way in understanding how people integrate multiple sources of information to perceive distance.
3D Audio Cueing for Target Identification in a Simulated Flight Task BIBAFull-Text 1836-1840
  Brian D. Simpson; Douglas S. Brungart; Robert H. Gilkey; Jeffrey L. Cowgill; Ronald C. Dallman; Randall F. Green; Kevin L. Youngblood; Thomas J. Moore
Modern Traffic Advisory Systems (TAS) can increase flight safety by providing pilots with real-time information about the locations of nearby aircraft. However, most current collision avoidance systems rely on non-intuitive visual and audio displays that may not allow pilots to take full advantage of this information. In this experiment, we compared the response times required for subjects participating in a fully-immersive simulated flight task to visually acquire and identify nearby targets under four different simulated TAS display conditions: 1) no display; 2) a visual display combined with a non-spatialized warning sound; 3) a visual display combined with a clock-coordinate speech signal; and 4) a visual display combined with a spatialized auditory warning sound. The results show that response times varied in an orderly fashion as a function of display condition, with the slowest times occurring in the no display condition and the fastest times occurring in the 3D audio display condition, where they were roughly 25% faster than those without the 3D audio cues.

PERCEPTION AND PERFORMANCE: Menus, Icons, and Visual Search

Effects of Menu Foresight on Information Access in Small Screen Devices BIBAFull-Text 1841-1845
  Susanne Bay; Martina Ziefle
An experiment was conducted to evaluate the effects of menu foresight (the number of menu items visible at a time on the display) on the usability of small screen devices. Cognitive factors (field dependency, locus of control and mental rotation ability) mediating the effects were assessed in order to identify the underlying processes of accessing information. Thirty-nine participants processed tasks on a simulated cellular phone where one, three or seven menu items were presented on the display. Search time, executed steps as well as ratings of the ease of use were collected. Results show that intermediate foresight (three items) led to the best performance. Highly field dependent users showed to have extreme difficulties when only one function was seen on the display whereas low spatial ability participants had most trouble with seven items displayed at a time. These findings suggest that cognitive processes of prestructuring information account for the effects of menu foresight.
A Queuing Network Model for Visual Search and Menu Selection BIBAFull-Text 1846-1850
  Ji Hyoun Lim; Yili Liu
Random menu search is a task component involved in many human-machine interfaces and has been modeled with various cognitive models including ACT-R and EPIC. Based on a review of empirical data in menu search and strengths and limitations of existing models, this article proposes a model that is based on the queueing network approach, which has been successfully applied in some other task domains (e.g., response time, driver performance). The queueing network model for random menu selection was implemented and evaluated through model simulation. In contrast to existing models that rely on multiple task-specific strategies to account for performance and eye movement data, the queueing network model uses only one strategy already employed in an existing cognitive model to account for the same data. The value of this "minimal task strategy" approach for modeling complex menu search tasks is discussed, based on the reported findings of the queueing network model and a comparison to existing models.
Semantic information influences the degree to which human observers perceive detail and intricacy within an icon BIBAFull-Text 1851-1854
  A. Forsythe; N. Sheehy; M. Sawey
Following the Boucart & Humphreys (1995) method, this paper reports a study in which response time to three groups of semantically related icons were examined. This study was used as a model by which to examine the ability of human observers to attend solely to one icon property without being influenced by other salient icon information. Humans are easily influenced by their experience of an icon: they tend to judge very simple, but unfamiliar icons (as defined by an automated analysis) as complex (Forsythe et al., 2003). This means that when humans are unreliable judges about the degree of detail or intricacy in an icon. The degree of detail or intricacy in an icon is one property is that lends itself to automation (Forsythe et al., 2003). As a decision-making aid, an automated system would make the process of icon development and modification a less speculative, more cost-effective activity.
Eye Movement Measures of Performance on Visual Search Tasks: Equating the Baselines of Task Performance BIBAFull-Text 1855-1859
  Bradley Chase; Erik Viirre; Julie Kwak; Shawn Wing; Karl Van Orden
Previous research suggests that eye measures can indicate decrements in performance on a visual tracking task due to increased difficulty in task execution from fatigue-induced conditions (Van Orden, 2000). In order to examine the sensitivity of eye movement to increased cognitive workload as indicated by difficulty of task, we chose a visual search paradigm. Using a basic visual search task, we studied the effects of increased task difficulty on subject performance and their corresponding eye measures. Results show a decrease in performance as the number of objects on the screen increase. What results could be expected if differences in individual abilities to perform visual search were controlled? This experiment looks at one method that can be used to control for individual differences in visual search abilities.
Local Density Guides Visual Search: Sparse Groups are First and Faster BIBAFull-Text 1860-1864
  Tim Halverson; Anthony J. Hornof
Visual search in an important aspect of many tasks, but it not well understood how layout design affects visual search. This research uses reaction time data, eye movement data, and computational cognitive modeling to investigate the effect of local density on the visual search of structured layouts of words. Layouts were all-sparse, all-dense, or mixed. Participants found targets in sparse groups faster, and searched sparse groups before dense groups. Participants made slightly more fixations per word in sparse groups, but these were much shorter fixations. The modeling suggests that participants may have attempted to process words within a consistent visual angle regardless of density, but that they were more likely to miss the target if the target was in a dense group. Furthermore, it was found that the participants tended to search sparse groups before dense groups. When combining densities in a layout, it may be beneficial to place important information in sparse groups.

PERCEPTION AND PERFORMANCE: Perception & Psychophysics

Mobile Video: A Study of Quality Perception BIBAFull-Text 1865-1869
  Clyde Heppner; Matrese Benkofske; Robert Moritz
This paper presents an evaluation of the perception of streaming multimedia quality when delivered over a limited bandwidth, third generation (3G) wireless data network. The study has three primary objectives: 1) measure the perceived quality of the multimedia experience as a function of frame rate, audio fidelity and data connection speed, 2) identify where the perceived quality of the multimedia experience shifts from being acceptable to unacceptable, and 3) identify the optimal combination of frame rate, audio fidelity and connection speed that provides the best customer experience. Analysis was conducted using Response Surface Methodology (RSM). RSM was used to identify how the three parameters of frame rate, audio stream bit rate and data connection speed interact and affect significant shifts in the perceived quality of the multimedia experience. Results identify the parameters and their characteristics that are related to shifts in the perceived quality across five types of multimedia content. The findings of this study are used to guide multimedia content developers on how to create (i.e., coding and encoding) multimedia content to ensure the best possible experience over limited bandwidth 3G wireless data networks. In addition, this research has implications for the design of future mobile data networks that will use quality of service technologies to ensure the best possible customer experience.
The Effects of Alarm Mistrust and Signal Duration on Alarm Reactions and Perception of Alarm Validity BIBAFull-Text 1870-1874
  Corey K. Fallon; James P. Bliss; Nicolae Nica
Researchers have begun examining variables that may moderate the degrading effects of alarm mistrust on alarm reaction performance. We examined alarm systems of varying reliability levels (60 or 80 percent true alarms) that generated either short or long duration alarms. We studied the impact of these variables on participant response frequency and perception of signal validity. The researchers sampled 40 Old Dominion University psychology students. We predicted that participants would rate long duration alarm signals as more representative of a valid signal. We also believed that participants would use the representativeness heuristic as a response strategy. The results partially supported our hypotheses. Participants rated the long duration signals as significantly more representative of a valid signal (p<.001). However, although participants responded significantly more often to long duration alarms (p<.01), participants in the 80% reliability group responded to significantly more alarms than those in the 60% reliability group (p=.02). The performance results are inconsistent with our hypothesis. Although participants perceived the long duration alarms to be more representative than the short, they did not base their response strategy entirely on alarm representativness. Despite these unexpected findings, the results suggest that alarm signal duration has a significant impact on alarm response frequency. Therefore, designers of complex systems may be able to moderate response degradation due to unreliability by designing systems that generate long duration alarm stimuli.
Length and Area Estimation with Visual and Tactile Stimuli BIBAFull-Text 1875-1879
  Merrill Sapp; Douglas J. Gillan
Why do the psychophysical functions for line length (linear) and area (compressive) differ and do they differ for both the tactile and visual modalities? Experiments 1A and B examined the effects of a two-dimensional perception on psychophysical functions for visual perception. Participants used magnitude estimation to judge the diameter, area, and circumference of a set of 14 circles. The psychophysical functions for diameter was approximately 1.0, for area was approximately .60, and for circumference was above 1.0, indicating that two-dimensional perception, per se, does not cause the compressive function for area. Obtaining spatial information without vision can be important for people with demanding graphically based decision-making tasks and people with visual impairments. Tactile interfaces provide an alternative way to display and obtain information. Do the tactile and visual modalities process spatial information in similar ways? Experiment 2 examined the correspondence between visual and tactile perception. Participants touched, but did not see, a series of circles. For each circle they judged diameter, area, and circumference. Psychophysical functions for diameter length, circumference length, and area of a circle estimated by tactile perception in Experiment 2 were comparable to those for visual perception.
Performance Operating Characteristics for Spatial and Temporal Discriminations: Common or Separate Capacities BIBAFull-Text 1880-1884
  J. E. Thropp; J. L. Szalma; P. A. Hancock
Resource-sharing between spatial and temporal processing was investigated using dual task methodology to construct performance operating characteristics. Spatial tasks involved discrimination of line length and temporal tasks involved discrimination of duration. Preliminary results suggest that a tradeoff occurs within the easier task of the two difficulty levels, but that a simple tradeoff is not observed at the more difficult level. This pattern of results suggests that the relationship between spatial and temporal perception varies according to difficulty level. That is, the degree to which the processes share common capacities varies as a function of the metrical characteristics of stimuli to be processed.


Beyond Trends: A Framework for Mapping Time-Based Requirements and Display Formats for Process Operations BIBAFull-Text 1885-1889
  John Hajdukiewicz; Peggy Wu
Trends have been extensively used in operations to monitor and manage evolving process situations. They provide detail about process variables but can take up significant screen space, potentially occluding other important monitoring parameters. As more data becomes available to the operations team, trends could proliferate and overload the operator. This paper presents the time-based information needs generated from plant personnel interviews, and discusses four existing and six alternative formats for displaying time-based information to tackle this problem. A framework was also developed to link the requirements to design options. The framework can be used to assess the benefits and limitations of the display options and help inform design based on the conditions of use in operations.
The Effects of Task Load on Performance and Cerebral Blood Flow Velocity in a Working Memory and a Visuomotor Task BIBAFull-Text 1890-1894
  Marla Zinni; Raja Parasuraman
This study examined the use of transcranial Doppler ultrasonography (TCD) as a tool to measure mental effort (as indexed by cerebral blood flow velocity) with increases in task load. Two tasks were chosen for this study based on their applicability to the task of piloting, a working memory (digit span) task and a visuo-motor tracking task. Based on previous findings of a possible relationship between mental workload and cerebral blood flow velocity it was hypothesized that both tasks would exhibit an increase in cerebral blood flow velocity in relation to baseline and that blood flow velocity would increase with increases in task demand. Although performance and subjective measures of mental workload indicated increased levels of effort to perform the digit span and tracking tasks as a function of task load, no systematic change in blood flow velocity was found with task demand in either task. Future work is needed to validate the use of TCD as a workload measurement tool.
The Role of Highlighting in Visual Search through Maps BIBAFull-Text 1895-1899
  Christopher D. Wickens; Michael S. Ambinder; Amy L. Alexander; Marieke Martens
An experiment was conducted in which participants performed a simulated vehicle dispatching task using a map display with two information domains. The intensity of one information domain was varied to examine the effect on processing the information in a cluttered display. Response times were recorded for questions either requiring focused attention on a particular information domain or divided attention between the two information domains. The results of the present experiments indicate that it is possible to "declutter" a display without erasing any information. By "lowlighting" one information domain and keeping the other domain at a fairly high intensity level, performance on tasks requiring divided attention is optimal, as is performance on tasks requiring focused attention to one domain exclusively. These results are also discussed in conjunction with a computational model of the effects of discriminability and salience on performance in a cluttered display with variable intensity codings used to visually segregate different domains of information.
Manipulating Optical Looming to Influence Perception of Time-to-Collision and Its Application in Automobile Driving BIBAFull-Text 1900-1904
  Zhonghai Li; Paul Milgram
Direct manipulation of optical looming provides convincing evidence of the contribution of optical looming in estimating time-to-collision (TTC). Precise manipulation of optical looming cues can be easily accomplished through computational scaling of (real or virtual) objects without impinging upon the naturalness of the task. This paper first discusses three ways to manipulate optical looming by scaling object size in order to influence perception of TTC. Then two principles affecting the implementation of optical looming manipulation are addressed. Next by revisiting the data of previous research, influences of knowledge about the optical looming manipulation and practice on the effect of optical looming manipulation are discussed. This supports our proposed principles and confirms the possibility of introducing the concept of optical looming manipulation into actual automobile design. Finally a potential application of optical looming manipulation, a dynamic brake light system, is proposed for automobile driving, to reduce the frequency of rear-end collisions. Issues in implementation of such a system and future research to validate it are also identified.
The Effect of Practice on Visual Change Detection in Computer Displays BIBAFull-Text 1905-1909
  John L. Neumann; Paula J. Durlach
People are sometimes unable to detect changes in their field of view, especially when the change coincides with a distraction. This failure to detect visual changes is known as change blindness. Our research on change blindness is motivated by the increasing use of complex digital displays in both military and industrial process control systems. We are interested in the extent to which important changes in displayed information might be missed, and methods to decrease vulnerability to change blindness. The present study examined whether practice detecting specific changes would lead to better change detection performance in general. Participants practiced detecting specific visual changes, such as an icon changing from blue to red, using the flicker paradigm with feedback given after each trial. Practice did lead to improved detection performance for the practiced changes (i.e. the blue to red changes). As performance improved, reaction time declined as well. To assess the generality of this effect, following practice, participants were given a transfer test in which changes that had not occurred during practice were scheduled (e.g., green to yellow changes or icon shape changes). Performance on these novel changes was significantly worse than for the practiced changes and there was no significant difference between the within-category changes (such as green to yellow instead of blue to red), and the between-category novel changes (the shape changes). These results therefore suggest that the improvements observed were specific to the changes practiced. On the other hand, the possibility exists that the procedure used actually taught participants to ignore the features that changed in transfer. During practice, these features were presented, but never changed. If participants learned to ignore these features during practice, that would work to oppose any generalization of heightened visual attention. This and other factors that may have affected performance are discussed.
Content is King: The Effect of Content on the Perception of Video Quality BIBAFull-Text 1910-1914
  Philip Kortum; Marc Sullivan
This paper describes a study which examined the effect of video content on viewers' perception of the picture and sound quality of that content. 40 participants viewed 20 different clips of major studio release movies that were 2 minutes in duration. Each clip was encoded at five different rates (490 kbps, 771 kbps & 1100 kbps, VHS and DVD). Each participant saw each clip only once and the level at which that clip was encoded was selected from a counter balanced list. Results indicated that desirability of the content played a significant role in a viewer's subjective ratings of the sound and video quality for a particular clip. It was found that the sound and picture quality of highly desirable content (as determined by each viewer) was rated significantly higher than content that was deemed neutral or undesirable. The study has implications for selecting content for subjective video quality studies.
When Dogs Fly: The Roles of Context and Stimulus Type in Predicting Non-Amnesic Visual Search BIBAFull-Text 1915-1917
  Valerie K. Sims; Derek D. Diaz; Linda U. Ellis; David Sushil
The present study examined whether search memory is facilitated by the presence of ecologically congruent cues. Participants completed a visual search task in which they had to decide whether one or two targets were present in an array of 12 items. Reaction time and eye movements were recorded. Targets consisted of either organic stimuli (person, dog, bird), artifacts (jets) or symbols (stars or a backwards 'S'). These were placed on one of three backgrounds (neutral gray, sky, or grass). Reaction times showed that search memory was greatest for organic stimuli (people, dogs), followed by complex symbols, and finally stimuli that are most associated with aerial searches. Eye movements showed a similar pattern of results. This pattern of data suggests a continuum in the reliance on inhibitive markers during visual search, such that naturally paired stimuli and backgrounds may be more likely to yield nonamnesic searches.
Haptic Perception of Affordances of a Sport Implement: Choosing Hockey Sticks for Power Versus Precision Actions on the Basis of Feel BIBAFull-Text 1918-1922
  Philip Hove; Michael A. Riley; Kevin D. Shockley
The present study investigated how changing the mass distribution of a hockey stick influenced the perceived affordances of a stick's utility for performing either a precision or power action. Top-weighted sticks were preferred for executing precisely controlled movements, both before and after using the stick to complete an interception action task. Initially, participants in the power condition preferred the bottom -weighted stick. However, once participants performed the power condition action task, they preferred a stick with a mass concentration closer to their point of grasp. These results indicate that a held object's perceived affordances are influenced both by its mass distribution, and the perceiver's level of experience using the tool for a given action. Human factors consideration include designing hand-held sporting equipment that capitalizes on people's sensitivity to an object's mass distribution.

PERCEPTION AND PERFORMANCE: Speed Perception, Spatial Reference Systems, and Vigilance

Judgments of Speed of Self-Motion: Modeling the Relative Effects of Speed and Altitude Change BIBAFull-Text 1923-1927
  John M. Flach; Asad Ali Junaid; Rik Warren
Empirical studies consistently show that judgments of the speed of self-motion are influenced by changes in the altitude of an observer. In general, a given actual speed is judged to be relatively faster from a lower altitude and relatively slower from a higher altitude. Similarly, loss of altitude can be accompanied by a false perception of increasing speed, while increases in altitude can be accompanied by a false perception of loss in speed. The direction of these effects is consistent with the Global Optical Flow Rate (GOFR) Hypothesis. However, the pattern of effects is not proportional to the ratio of velocity to altitude as predicted by the GOFR Hypothesis. An alternative model is presented that predicts additive effect of speed and altitude changes on speed perception.
Kinesthetic Cueing for Manual Control in Rotated Frames: Compact Input Devices and User Technical Background BIBAFull-Text 1928-1932
  B. D. Adelstein; S. R. Ellis; K. D. Smith; R. B. Welch
The present study of user's capacity to utilize hand pose to sense the control coordinates of a manipulative task environment extends previous studies of this cueing method to examine more widely used trackball and trackpad computer input devices. Test subjects controlled the input devices with their right hand, while their left hand was aligned with an adjustable rigid object that provided the kinesthetically sensed cue. Results show that the kinesthetic cue reduces extraneous path motion, as previously seen for pen-tablet devices. Analysis indicates that when the cue was present, individuals having more exposure to geometry and mathematics slowed their movements, possibly indicating additional mental processing to monitor motion. Without cueing, the trackpad users showed worse performance than trackball users at large rotational disturbances. However, trackpad users showed the greatest improvements when the cue was added.
Choosing Frames of Reference: Perspective-Taking in a 2D and 3D Navigational Task BIBAFull-Text 1933-1937
  Farilee E. Mintz; J. Gregory Trafton; Elaine Marsh; Dennis Perzanowski
This study investigates how frames of reference are chosen in a dynamic navigational task. Participants issued verbal instructions to an animated robot and were provided with one of three views for navigating the animated robot around a virtual world. The different views included a flat two-dimensional (2D) North-up map, a three-dimensional (3D) robot's eye view of the world, and a 3D view from behind the robot (3D-Camera) in which depth cues were manipulated. Our results show people adopt an egocentric frame of reference when depth cues are salient and an exocentric reference frame when depth cues are absent. The results suggest the absence or presence of depth cues is a critical component in choosing a reference frame. We discuss the extension of Bryant and Tversky's (1999) theoretical framework to a dynamic environment, such as navigation.
Investigation of the Figure Superiority Effect in Sustained Attention BIBAFull-Text 1938-1942
  Christina A. Proctor; Nathaniel R. Ungar; Joel S. Warm; Gerald Matthews; William N. Dember; Tyler Shaw
This study examined whether enhanced perceptual discrimination for targets presented on figural than on ground elements, namely the figure superiority effect, extends to performance on vigilance or sustained attention tasks. In the experimental condition, targets requiring discriminations of line orientation were presented on figure-ground displays that could be organized as a face, a seahorse, and a pineapple, respectively, against a uniform black or white background. A control condition was also employed in which the same targets were presented on a bipartite black/white field. Figure-ground organization did not differentially effect signal detection in the experimental condition. However, perceptual sensitivity was significantly greater for signals appearing in the meaningful figure-ground display than in the control display, which lacked a meaningful figure-ground segregation. Consequently, meaningful figure-ground organization can be a critical psychophysical factor in controlling sustained attention.
Feature Presence/Absence Modifies the Event Rate Effect and Cerebral Hemovelocity in Vigilance Performance BIBAFull-Text 1943-1947
  Todd D. Hollander; Joel S. Warm; Gerald Matthews; Kevin Shockley; William N. Dember; Ernest Weiler; Lloyd D. Tripp; Mark W. Scerbo
Observers monitored displays of five circles for the presence or absence of a line in one of the circles during a 40-min vigil. Displays were updated 6, 12, or 24 times/min (event rate). Signal detections varied inversely with event rate when observers monitored for the absence of the distinguishing feature but not when monitoring for the presence of that feature and judged the workload of their assignment to be greater when monitoring for feature absence than presence. In addition, the availability of information processing resources, as indexed by transcranial Doppler sonography measurements of cerebral blood flow, was exhausted more rapidly when observers monitored for feature absence than for feature presence. This effect was limited to the right hemisphere. The results are consistent with the view that detecting feature absence is more capacity demanding than detecting feature presence and with previous brain imaging findings indicating right hemispheric control of vigilance.

PERCEPTION AND PERFORMANCE: Workload and Performance

Effects of Varying the Threshold of Alarm Systems and Task Complexity on Human Performance and Perceived Workload BIBAFull-Text 1948-1952
  Ernesto A. Bustamante; Brittany L. Anderson; James P. Bliss
Using a dual-task paradigm, we examined how alarm system detection threshold and task complexity affected human performance and perceived workload. We hypothesized that using an alarm system would improve task performance and lower perceived workload, particularly when task complexity was high and at the medium threshold level. Twenty-one students from Old Dominion University participated in this study. Results showed that alarm use improved performance during low task complexity. For high task complexity, improvement was accomplished only when alarm system threshold was low or intermediate. Results also indicated that changing the alarm system threshold affected performance only under high task load conditions. Optimal performance was achieved by setting the threshold of the alarm system at its lowest level. The use of alarms reduced workload under both low and high task complexity levels, but only when the threshold was high.
Workload and Performance: A Field Evaluation in a Police Shooting Range BIBAFull-Text 1953-1957
  Adams Greenwood-Ericksen; Tal Oron-Gilad; James L. Szalma; Shawn Stafford; Peter A. Hancock
One vital responsibility of all law enforcement officers lies in their obligation to defend themselves and those around them in the event of a violent threat. The best tool available to them to perform this duty is their sidearm and their skill in using it. To evaluate the efficiency of this tool use, seventy-one police officers participated in a field study examining the relationship between workload and shooting performance. Use of linear re