bluuebunny/crossref_metadata_2025 huggingface dataset:
Individual Differences in Computerized Test Performance for Systems Integration in Cockpit Management
Authors: Chambers Randall M. , Whitmore Mihriban
Published: January 2012

Assessments of cognitive performance profiles, personality variables, cognitive workload relationships, and physiological indices suggest that there may be important individual differences in cognitive test performance and style during the execution of cockpit management tasks. Stability of cognitive performance profiles during repeated measures in a flight simulator and in human factors test facility suggest significant subject effects on performance of nine computerized cognitive tests within a complex cognitive assessment battery. Highly significant test effects were demonstrated and characterized by individual differences in performing them during the execution of cockpit management tasks. Results showed important clustering of the cognitive tests (Following Directions, Mark Numbers, Numbers and Words, Word Anagrams, Missing Items, Route Planning, Tower Puzzle, Information Purchase, and Logical Relations) in which varying clusters differed significantly from other clusters and patterns. Cognitive performance on some tests were related to assessments of personality, physiological indices, cognitive workload, and proficiency in monitoring instrument displays. For the integration of advanced cockpit technology and human cognitive performance capabilities in advanced cockpit management systems, inferences may be drawn which describe the types of cognitive performances which may be efficiently integrated with automated instrumentation in the cockpit. The design and integration of performance management tasks for the advanced cockpit includes consideration of the individual differences in performance of specific cognitive tests and the proficient performance of their components in the management system.
An Individual Differences Approach to Fitness-for-Duty Assessment
Authors: Kennedy Robert S. , Dunlap William P. , Turnage Janet J.
Published: January 2012

It is reported that performances in the workplace are affected by alcohol, drugs or other stresses. Experimental studies largely confirm these reports but translation of laboratory findings to job outcomes is difficult. If tasks indexed such a loss to a standard substance or holistic task, this index could provide the context to assist management decisions regarding standards and shift schedules. This paper reports changes with graduated dosages of alcohol on a standardized set of performance tests and refers to the approach as “dose equivalency.” Subjects (N=20) were tested to stability on 10 tests from the Automated Performance Test System (APTS). After administration of sufficient alcohol to achieve .15 blood alcohol level (BAL), using breath as the independent variable, the descending branch of the BAL curve was followed by measuring performance at set levels of alcohol. A dose-response relationship was confirmed for all performance tests (P < .01), and multiple regression was used to select subtests that maximally predicted alcohol level. Four subtests were combined into a linear composite that related well to alcohol levels above 0.05 BAL. The performance decrements on APTS were indexed to performance decrements on the Armed Services Vocational Aptitude Battery (ASVAB). Performance equivalency and dose equivalency relationships were successfully demonstrated so that: (1) a regression equation can be created that translates reductions in APTS performance, due to any other treatment, into ASVAB-equivalent performances; and (2) a regression equation can be created which translates reductions in performance due to such agents or treatments into units of percent blood alcohol.
A Most Critical Warning Variable: Two Demonstrations of the Powerful Effects of Cost on Warning Compliance
Authors: Dingus Thomas A. , Hathaway Jill A. , Hunn Bruce P.
Published: January 2012

The effects of cost on warning compliance have been demonstrated in several previous studies. These studies have shown that cost reduction can dramatically increase compliance with a warning label's intent. The current paper describes two studies which support these previous findings under situations of household consumer product and recreational protective equipment use. In addition, these studies demonstrate that cost reduction can positively influence behavior under circumstances known to be detrimental to warning effectiveness. Such circumstances include low risk perception, familiar products, and inadequate warning labels/signs. These studies also show that increasing the cost associated with warning compliance, even a seemingly minor amount, can have devastating effects on compliance rates. These results indicate that the greatest effort possible should be taken to reduce compliance cost in hazardous situations when warnings are relied upon for hazard control.
A Model for Designing and Evaluating Product Information
Authors: Miller James M. , Frantz J. Paul , Rhoades Timothy P.
Published: January 2012

While a variety of models and methodologies exist for the design of products, few have been advanced for the design of product accompanying information such as safety warnings and instructions. This paper presents a model for designing and evaluating product information. The model has five primary stages: Product Type Investigations, Product Use and User Group Research, Information Design Criteria and Prototypes, Evaluation and Revision, and Post Sale Evaluations. The model emphasizes the need to: a) design product information in conjunction with the design of the product itself; b) analyze product features which affect user expectations and behaviors; c) identify the hazards associated with use and likely misuse of the product; d) research user perceptions and expectations regarding product functioning and hazard characteristics, and e) evaluate product information using methods and criteria consistent with the goals of each component of product information.
Human Factors in Intelligent Vehicle-Highway Systems: A Look to the Future
Authors: Mast Truman
Published: January 2012

To achieve greater mobility and safety in highway travel, the Intelligent Vehicle-Highway System (IVHS) concept links the vehicle, driver, highway, and traffic management team using advanced communications and computer-controlled technology. In the near future we will see considerable change in the basic nature of the driving task and the way traffic is managed in the U.S. These changes are driven by the urgent need to address the serious problems of increased traffic congestion, energy waste, high fatality and injury rates, and environmental pollution. Human factors considerations are critical in the design and operation of IVHS. The driver-vehicle and driver-highway interfaces will be altered and will require optimization. Traffic control centers will perform more complex functions and will need the best possible ergonomic design. Traffic management teams will need to be properly configured and trained to meet effective performance criteria for more demanding work conditions. This paper will discuss IVHS human factors issues from the perspective of the Federal Highway Administration (FHWA). It will also review FHWA's IVHS human factors research and development needs and strategies for the near future. The issues and planned FHWA activities for IVHS human factors will be discussed in terms of four elements: Advanced Traffic Management Systems (ATMS), Advanced Traveler Information Systems (ATIS), Commercial Vehicle Operations (CVO), and Advanced Vehicle Control Systems (AVCS).
An Observational Study of User Interface Design Practice
Authors: Due Benedicte , Jorgensen Anker Helms , Nielsen Janni
Published: January 2012

Most studies of decision making in user interface design have been based on post-hoc interviews. To convey the realm of user interface design practice we conducted a longitudinal study of one designer in an organisation while designing an in–house database system. We applied the participant observation method. The observations revealed that the design took place in a highly turbulent organisational context, the working situation was extremely fragmented, and the information available on the users' tasks was incomplete and contradictory. Under these circumstances the designer adopted an ad–hoc design strategy. No specifications and plans were made. Instead, prototypes were developed aiming at getting feedback from users; however the users were much more concerned with organisational consequences of the system. In the prototypes, the user interface was literally designed from the upper left corner of each screen. Little explicit evaluation was made and drafts became promoted to the real system. Thus, the decisions became disjointed incremental to the existing systems and work practise, i.e. the decision strategy was muddling through.
Capturing and Representing Decision Processes in the Design of an Information System
Authors: Coury Bruce G. , Motte Susan , Seiford Lawrence M.
Published: January 2012

Incorporating the decision processes used by people in complex decision tasks is one of the most significant challenges facing designers of information systems. The need to capture and represent those decision processes is a fundamental part of the development of any information system and requires input from users. The purpose of this paper is to present an approach to the design of information systems that identifies the information needs of the user, reveals the reasoning process and decision strategies employed by users to make decisions, and represents those processes and information requirements in such a way as to enhance system development. The research combines user needs analysis with cognitive modeling to provide the basis for the design of a prototype information system. The paper shows how user needs analysis provides the knowledge and information necessary to cognitively model the decision processes of users in a particular problem domain.
Advanced Control Room Evaluation: General Approach and Rationale
Authors: O'Hara John M. , Wachtel Jerry
Published: January 2012

Advanced control rooms (ACRs) for future nuclear power plants (NPPs) are being designed utilizing computer-based technologies. The U.S. Nuclear Regulatory Commission reviews the human engineering aspects of such control rooms to ensure that they are designed to good human factors engineering principles and that operator performance and reliability are appropriately supported in order to protect public health and safety. This paper describes the rationale and general approach to the development of a human factors review guideline for ACRs. The factors influencing the guideline development are discussed, including the review environment, the types of advanced technologies being addressed, the human factors issues associated with advanced technology, and the current state-of-the-art of human factors guidelines for advanced human-system interfaces (HSIs). The proposed approach to ACR review would track the design and implementation process through the application of review guidelines reflecting four review modules: planning, design process analysis, human factors engineering review, and dynamic performance evaluation.
On Validating Human Performance Simulation Models
Authors: Liao Jianqiao , Milgram Paul
Published: January 2012

This paper addresses some of the difficult and elusive problems associated with validating human performance simulation models. Simulation validity can be subclassified into input validity, structure validity and output validity. Of these, output validity is the most objective and also the most important, because it determines whether or not the purpose of the modelling effort can be met. In testing for output validity analysis of variance alone is not sufficient for validating human performance simulation models, as is often taken for granted by many researchers. A more systematic approach is proposed and its implications discussed. The approach is based on considering analysis of variance in terms of the power of the test and a predetermined level of acceptable differences between model and reality.
Data Bridging: Statistical Methods for Integrating Results across Studies
Authors: Han Sung H.
Published: January 2012

A procedure is described for integrating data sets from several studies based on a sequential research strategy. A data bridging technique is used so that the results of three previous studies can be combined to build integrated second-order empirical models. The previous studies investigated 10 independent variables, but 16 uninvestigated interactions from the complete set of items in a second-order model were not investigated in these studies. To select the best data points for examining these uninvestigated interactions, the maximization of |X'X| criterion was used. A computer program was developed to calculate the determinant value of X'X matrix for each candidate data point. Each selected data point was then analyzed to determine multicollinearity of the uninvestigated interactions. From these analyses, six additional data points were selected to examine the 16 uninvestigated interactions. Results from six additional data points along with the previous data sets were combined to build second-order empirical models using polynomial regression. The empirical models were then analyzed to choose the best models in terms of statistical properties such as variances of coefficients and prediction variances of the models. This procedure is discussed as a method for integrating data collected through sequential experimentation into an empirical model describing the functional relationships among independent variables. This approach increases the generalizability of data used in the design and evaluation of human factors interfaces which involve a large number of factors.
The Epistemological Basis of Human Factors Research and Practice
Authors: Meister David
Published: January 2012

Different types of knowledge (experimental, empirical, and experiential) combine with assumptions, beliefs, models, and theories to determine what Human Factors (HF) researchers and practitioners study and do. In research, problems of epistemology and meaning arise because one must interpret the meaning of effects produced in a study. In design, epistemology underlies the relationship between behavioral design variables and their anticipated performance effects.
Testing a Subjective Metric of Situation Awareness
Authors: Vidulich Michael A. , Hughes Edward R.
Published: January 2012

The present research tested a subjective situation awareness (SA) metric, called the SA-SWORD technique. The SA-SWORD technique was an SA adaptation of a subjective workload assessment tool (called the Subjective WORkload Dominance (SWORD) technique). The utility of the SA-SWORD technique was tested in a simulator evaluation of cockpit displays, using Air Force pilots as subjects. Two displays were compared: the Fire Control Radar (FCR) display, and the Horizontal Situation Format (HSF) display. The FCR display provided a functional simulation of current air-to-air radar displays. The HSF was a map-like display that combined data-linked information from outside sources (e.g., an AWACS) with the aircraft's own data to provide a bird's-eye, symbolic view of the entire area. Following collection of the performance data, SA-SWORD scores were collected. Pilots rated their SA higher when using the HSF display, than when using the FCR display. An implication of the current results is that subjective SA metrics can play a useful role in a system evaluation. More specifically, the current results suggest that the SA-SWORD technique can be a useful tool for assessing subjective SA.
A Multifaceted Approach to Enhance Operator Services for Regional Telephone Companies
Authors: Lysaght Robert J. , Springer Carla J. , Moritz Robert R. , McCain Jody E.
Published: January 2012

Aproximately 9 to 10 billion calls are handled by telephone operators of the Bell Operating Companies throughout the U.S.A. on a yearly basis. Bell Communications Research has an Operator Services Ergonomics district that employs a multifaceted approach to improving operator efficiency and comfort, and providing guidance on both the operator and customer human interfaces for new services. The approaches taken represent a recognition of several key factors that dictate and/or influence the type of test and evaluation conducted and how the results from such tests are conveyed to decision makers.
Development of a Measure of Training Program Effectiveness for Nuclear Power Plants
Authors: Connelly Edward M. , Haas Paul , Van Hemel Susan B. , Wreathall John
Published: January 2012

The approach taken to develop measures of training program effectiveness recognizes that many subject matter experts (SMEs) with varying viewpoints on training effectiveness are working to insure nuclear power plant (NPP) safety. These viewpoints include:

Training program developers;

Nuclear site personnel: instructors, supervisors, managers;

Nuclear Regulatory Commission (NRC) personnel;

Contractor inspection/audit personnel;

Industry professional organization personnel;

University researchers.

SMEs from each of these viewpoints have an impact, via their work, on NPP training effectiveness and consequently on NPP safety. Their training program assessment strategies are in-place, operational entities which are used to guide their work. Since those assessment strategies are largely unknown because of their unstated, subjective form, several critical issues arise:

1. Are the SMEs' training assessment strategies different? 2. If the training assessment strategies are different, are they equivalent, or are they working unknowingly toward somewhat different goals? 3. Can a measure of training effectiveness be built by modeling SMEs' assessment strategies?

To answer these questions we must model the effectiveness rating strategies of various SMEs whose ratings are important to training; i.e., build an measure of effectiveness (MOE) representing the rating strategy of a sample of those SMEs. A quantitative model of these assessment strategies permits a broad review of them by all interested parties and provides the basis for building a broadly accepted training program MOE. Major differences in assessment strategies can be examined to determine whether they are appropriate to the different points of view or are in conflict. This paper describes the basic concepts of building effectiveness measures, the methodology used to build the measures, a summary of the measures developed from NRC and industry sources, and an analysis of the differences among SMEs' measures.
Scheduling Information Feedback to Enhance Training Effectiveness
Authors: Nicholson Diane E. , Schmidt Richard A.
Published: January 2012

If skill learning is evaluated in terms of performance on retention or transfer tests, recent evidence has shown that systematically reducing the frequency of augmented information feedback in training facilitates learning, as compared to practice with augmented feedback on every trial. However, in past experiments feedback frequency and scheduling have been confounded. In the present experiments, we separated these variables, showing that both reduced feedback frequency, and the particular scheduling of feedback presentations, are important variables for maximizing learning.
Contrast Sensitivity and English Letter Recognition
Authors: Poynter Doug
Published: January 2012

Threshold luminance contrast for letter recognition is dependent upon the amount of color contrast present, the background luminance, letter size, the age of the observer, and level of glare. Mathematical descriptions of these relationships are presented, and a model of contrast sensitivity composed of these functions is proposed. Limitations of the model, initial tests of its validity, and potential applications are discussed.
Effects of Display Luminance on the Recognition of Color Symbols on Similar Color Backgrounds
Authors: Crawford Robyn L. , Toms Mona L. , Wilson Denise L.
Published: January 2012

This study examined the effects of display luminance on the ability of human observers to recognize color symbols displayed against similar color backgrounds. The Signal Detection paradigm was utilized and subject sensitivity, as measured by d', was the primary measure of interest. The symbol colors were red, green, and blue. Background colors were .01 to .07 1976 CIE/UCS units distant from the symbol color. Luminance levels ranged from 11.85 cd/m2 to 127.25 cd/m2. The symbols were presented on a cathode ray tube (CRT) under ambient lighting of two lux. Display luminance was found to affect subject sensitivity, d', as a function of symbol-background color combination. The results imply that display luminance for the presentation of blue symbology on bluish backgrounds is optimal at 19 cd/m2. For the red and green symbol-background conditions, display luminance between 56 and 93 cd/m2 yields the best performance.
Cardiorespiratory Measures of Workload during Continuous Manual Performance
Authors: Backs Richard W. , Ryan Arthur M. , Wilson Glenn F.
Published: January 2012

Twelve subjects (six female) participated in a study designed to experimentally separate the effects of physical and cognitive effort on cardiac and pulmonary measures of workload. Cardiac (heart rate and variability), respiratory, and forearm muscle activity were measured while subjects performed a single-axis continuous manual tracking task. The central processing demands of the task were varied by changing the tracking system order over three levels: pure velocity, a combination of velocity and acceleration, and pure acceleration. The physical demands of the task were varied by requiring subjects to track either high or low amplitude sum-of-sines disturbance. RMS tracking error, subjective ratings, heart rate, and forearm muscle activity were sensitive to, but did not differentiate, the cognitive and physical manipulations; these measures increased as both tracking order and disturbance gain increased. However, the respiration measures dissociated under the physical and cognitive manipulations. Respiration rate increased with tracking order but not disturbance gain, while respiration amplitude increased with disturbance gain but not tracking order. Also, spectral power measures of respiratory activity and of cardiac activity at the respiration frequency (i.e., respiratory sinus arrythmia) dissociated for disturbance gain: respiratory power increased while cardiovascular power decreased as a function of increasing disturbance gain. These results verify the utility of a multiple-measures approach to the assessment of workload, and suggest the inclusion of respiration and cardiorespiratory interactions as workload measures.
Boutique Data Graphics: Perspectives on Using Depth to Embellish Data Displays
Authors: Carswell C. Melody
Published: January 2012

Embellishing simple graphs by adding perspective, “the 3-d look,” has become increasingly commonplace with the ready availability of graphics software. However, the effect of adding such decorative depth on the comprehension and recall of the graph's message has received little attention. The present study evaluated performance on common graphical formats (e.g., bar graphs, line graphs, and pie charts) constructed with and without the 3-d look. The addition of depth was associated with less accurate performance for subjects attempting to (1) estimate the relative magnitude of displayed values, (2) classify and describe trends, and (3) recall quantitative information about both specific values and trends. Although less accurate, subjects responded more quickly to the 3-d graphs when performing one type of trend classification. Line graphs, more than bar graphs or pie charts, were susceptible to the impact of decorative depth on performance. Further data suggest that the the use of 3-d designs, in addition to modifying performance, may influence the attitudes formed by subjects toward the information presented in the graphs.
Use of Visual Cues by Orienteers: An Analysis of Interview Data
Authors: Whitaker Leslie A. , Cuqlock-Knopp Grayson
Published: January 2012

Visual cues are critical elements in the successful navigation of off-road terrain. To examine the importance of visual cues and their use in navigational strategies, sixteen interviews were conducted with orienteers and military scouts using a semi-structured interview technique known as the Critical Incident Technique. Each interviewee described a specific navigation incident in which his (her) skill had been needed to navigate successfully. Probe questions were then used to elicit visual cues and strategies used by these off-road navigators to solve their navigation problems. The verbal protocols were analyzed in a split-half coding procedure. A randomly selected eight interviews were coded to determine the types of visual cues and strategies used. These categories were then used to code the remaining eight interviews. The five categories of visual cues used by the first half of the sample were the same used by the second half. Four categories of strategies were coded from the first half of the sample. These strategies applied to 94% of the strategies used by the second half of the sample. A subset of the verbal protocols was also coded using SHAPA 2, a verbal protocol analysis package. SHAPA was advantageous as a flexible code development system; however, data entry time was greater than for coding directly from the paper transcripts.
The Use of Aiding Techniques and Varying Depth Volumes to Designate Targets in 3-D Space
Authors: Solz Thomas J. , Reising John M. , Liggett Kristen K. , Lohmeyer Troy , Hartsock David C.
Published: January 2012

The purpose of this study was to determine the effectiveness of a hand tracker to designate targets using a three-dimensional (3-D) map. Three variables were manipulated: 1) hand tracker active volume, 2) aiding technique, and 3) target density. There were three different volumes (large, medium and small) in which the hand tracker operated. Each volume represented cockpit space in which hand tracker movements correlated to cursor movements on the screen. Two aiding techniques were referred to as contact aiding and proximity aiding. Contact aiding consisted of a color shade change to the target when the cursor penetrated the target volume. Proximity aiding consisted of an algorithm that selected the target closest to the cursor and thus changed its color shade. Two target densities, high (16 targets) and low (8 targets), were used. Speed and accuracy were measured in the designation of targets using a hand tracker. Results showed that proximity aiding in the medium volume space yielded the best performance.
Expanding the Envelope of Performance: Training Pilots to Use Helmet Mounted Displays
Authors: Seagull F. Jacob , Gopher Daniel
Published: January 2012

Helmet Mounted flight Displays (HMDs) of a through-the-window field-of-view (FOV) are widely used in modern aircraft for night vision. Unfortunately, pilots using such displays are susceptible to spatial disorientation due to the limited field-of-view and its consequent lack of orientation cues. This problem is especially pronounced when pilots move their heads, though this is precisely the behavior that enables them to counteract the limited FOV. The current experiment attempted to train pilots to move their heads without becoming disoriented. Twenty-five subjects participated in five treatment groups in a between-subjects design. Subjects piloted a simulated helicopter through a computer-generated winding canyon with either a single-eye HMD, or a binocular through-the-window “screen” display. Three control groups were trained using either (1) a binocular screen-display without a secondary task, (2) an HMD view without a secondary task, or (3) an HMD view with a secondary task presented in the center of the HMD FOV. The two remaining treatment conditions involved flying while carrying out a secondary task which required either (1) systematic head movement (displacement), or (2) systematic head-movement plus head re-orientation. Results indicate that after training, treatment groups completed significantly more flights without crashing using the HMD than did the control groups. They also had a significantly higher probability of surviving a given flight at any time. Treatment groups learned to increase their head movement, while control groups spontaneously reduced theirs. These findings indicate that spontaneous experience with an HMD does not lead to optimal performance. Development of attention control strategies focusing on the difficulties of HMDs increased considerably the ability of operators to cope with the problems.
The Implications of Data-Link for Representing Pilot Request Information on 2D and 3D Air Traffic Control Displays
Authors: Wickens Christopher D. , Miller Sonia , Tham Mingpo
Published: January 2012

Twenty-four subjects (seven ATC specialists and 17 pilots trained in fundamental ATC skills), performed a simulation in which they were required to evaluate pilot requests for flight plan changes, issued by aircraft depicted on their display. Some requests could be safely granted, whereas others would bring about a mid-air conflict with other aircraft. Subjects evaluated the requests in the context of an airspace depicted on either a conventional 2D planar display or a 3D perspective display. Requests were presented either as voice messages or were displayed visually, as if relayed via data-link, either printed at the bottom of the display or represented as vectors, emanating in the requested direction from the requesting aircraft. The results indicated that performance was generally equivalent with the 2D and the 3D display and was best with the auditory-verbal request mode. It was considerably slower with the print mode, presumably because of the greater scanning required. The spatial vector mode offered performance that was faster than print, but considerably less accurate. Particular deficiencies were noticed with the vector mode when it was used to present complex 3-dimensional requests in the context of the 3-dimensional display.
The Effects of Taxiway Light Geometry, Color, and Location on Position Determination by Pilots
Authors: Jentsch Florian
Published: January 2012

Lack of perspective cues or abundance of lights in airport taxiway areas have been problems leading to pilot disorientation when navigating on the airport surface. Possible human factors solutions include the introduction of perspective cues through shaped lights and the reduction of extraneous light signals with shielded lights. Thirty-two pilots participated in a laboratory simulation to evaluate the effects of taxiway light geometry, color, and location on determination of position. Two new systems (shielded and shaped lights) were tested against two traditional systems (blue edge lights and green centerline lights). Subjects had to determine their position on an airport map from static, out-the-cockpit views. Contrary to expectations, the two new systems did not lead to improved performance over the traditional systems in this simulation. In fact, the pattern of means suggested that performance was better with the traditional systems than with the new ones. In the case of the number of correctly identified positions, these differences were significant. Subjects' confidence and their actual performance in position determination did not correlate. Implications for studies investigating airport surface navigation systems are discussed.
Age Differences in the Legibility of Symbol Highway Signs as a Function of Luminance and Glare Level: A Preliminary Report
Authors: Schieber Frank , Kline Donald W.
Published: January 2012

Three experiments were conducted to investigate the effects of adult aging upon the legibility of simulated symbol highway signs. Each experiment employed a different set of lighting conditions: (1) daytime luminance, (2) nighttime luminance, and (3) nighttime luminance with glare. Young (ages 18-25) and middle-aged (ages 40-55) observers demonstrated small reductions in legibility when luminance was reduced from daytime to nighttime levels. However, older (ages 65-79) observers demonstrated marked losses in legibility distance with reductions in sign luminance. The introduction of a glare source (equivalent to approaching automobile headlights at 30 m) reduced sign legibility distance for the older observers but had no deleterious effects upon their young and middle-aged counterparts. The relative magnitude of the observed age, luminance and glare effects appeared to be equivalent across all signs examined.
Age Differences on a Paired-Associates Task: How Does Practice Type and Order Affect Training?
Authors: Gilbert D. Kristen , Rogers Wendy A.
Published: January 2012

The purpose of this research was to determine if manipulating the order and type of practice would affect the outcome of training for both young and older adults. We examined age differences in performance on a paired-associates task in which type and order of practice were manipulated. Two versions of a noun-pair associates task were used; in the consistent mapping (CM) version the noun-pairs did not change from trial to trial; in the varied mapping version (VM) the noun-pairs changed from trial to trial. The CM task allowed the subjects to learn the noun-pairs whereas the VM task required that subjects always refer to a key in order to perform the task. Two groups of subjects were trained and the order in which they received the CM and VM versions was manipulated between groups. There were group differences in initial performance on the CM task for both young and older adults. The data indicate that having performed the task at all provided some benefit in terms of reaction time. The subjects were able to acquire the skill of performing the task in the first version they performed and this skill acquisition aided their subsequent performance. In addition, the benefits of prior practice were longer-lasting for older adults relative to young adults.
Network Modeling of Nuclear Operator Procedures
Authors: Laughery Ron , Persensky J.
Published: January 2012

Research and evaluation on human factors issues can be very expensive owing to 1) the high cost of running experiments and 2) high inter-team variability which makes it necessary to run large numbers of subjects to get stable estimates of performance. Increasingly, the engineering disciplines are looking towards computer modeling as a means of predicting performance as a function of engineering design. Human factors engineering has that goal as well. This paper presents the results of a validation study that evaluated a human performance modeling technology termed task network modeling. Task network models were built of a crew executing two emergency procedures and one normal procedure. For each of these three procedures, one model was built reflecting the use of paper procedures and one reflecting the use of computerized procedures. Model predictions were then compared to data on actual crews performing under identical conditions. In general, the model predictions were representative of actual performance, although a number of issues arose that should be addressed prior to using these models as a technical basis for regulatory action.
Guiding Instruction in Hypermedia
Authors: Hillinger Michael , Leu Donald J.
Published: January 2012

While hypermedia can provide flexible and rapid access to information in multiple mediums its navigation can be daunting to an unfamiliar user. This paper describes a prototype hypermedia system for training the components of a turbine engine. Designed as a content-rich hypermedia substrate combined with an independent guide, the system provides the novice with structure without impeding exploration. Results of a comparative study indicate that users unfamiliar with the topic learn more when the guide is available while users already comfortable with turbine concepts learn targeted information better without the guide.
Virtual Reality as a Human Factors Design Analysis Tool for Architectural Spaces - Control Rooms to Space Stations I: Objective Measures
Authors: Hale Joseph P. , Dittmar Mary Lynne
Published: January 2012

One class of Virtual Reality (VR) applications is as a Human Factors design analysis tool for work areas and other architectural spaces. A study was conducted to compare subjects' qualitative and quantitative judgments of two “real” world control rooms at the Marshall Space Flight Center (MSFC) and their corresponding virtual counterparts. The overall Independent Variables (IVs) were World (Real/Virtual) and Room (PCR/SIM) with Gender and World Order (Virtual-Real/Real-Virtual) as blocking variables. Nested within Room were range and relative range estimations. Range estimations were comprised of two IVs: 1) Item (Object/Surface) and 2) the Item's Range from the observer (Near/Far). The relative range estimations were comprised of two IVs: 1) Field-of-View (FOV) (Same/Different, i.e., whether or not the subject can see both objects simultaneously in the same FOV) and 2) the objects' Distance from the observer (Close/Away). There appears little difference between real and virtual worlds in one's ability to differentiate and estimate gross distances and to discriminate small relative range differentials within the same FOV. For different FOVs, this discrimination ability starts to deteriorate in the real world and is lost in the virtual world. There is also a clear World main effect of increased time to make judgments in the virtual world. The different perceptions, and the longer response times, point to a level of filtering occurring in the virtual environment that must be carefully considered when deciding where and how to use VR as a Human Factors analytical tool.
Integrating Human Factors with Software Engineering Practices
Authors: Hefley William E. , Buie Elizabeth A. , Lynch Gene F. , Muller Michael J. , Hoecker Douglas G. , Carter Jim , Roth J. Thomas
Published: January 2012

Engineering processes and methodologies used in building tomorrow's systems must place a greater emphasis on designing usable systems that meet the needs of the systems' users and their tasks. This paper identifies the need for defining human factors and human-computer interaction (HCI) engineering activities that contribute to the design, development, and evaluation of usable and useful interactive systems, and presents a rationale for integrating these activities with software engineering and incorporating them into the system life cycle.
The Use of Word, Phrase and Intent Accuracy as Measures of Connected Speech Recognition Performance
Authors: Barry Tim , Solz Tom , Reising John , Williamson Dave
Published: January 2012

Eleven subjects participated in a study designed to test the accuracy of a newer-generation connected speech recognition system using a 49 word vocabulary likely to be used in an aircraft cockpit environment. The 49 vocabulary words were used to create 392 test phrases. These phrases were divided into three groups: Complex phrases, which contain more than five words, and two groups of Simple phrases, which contain 5 words or less. The simple phrases were divided into Simple Alternate and Simple No-Alternate phrases, depending on whether or not the phrase was the only one in the entire vocabulary capable of carrying out a particular action once recognition occurred. Performance of the recognition system was measured with three accuracy statistics: word accuracy, the most commonly reported statistic in speech recognition research, phrase accuracy, which is gaining popularity in connected speech recognition research, and intent accuracy, which is probably the most relevant statistic that could be reported in research of this type. Significantly different word, phrase, and intent accuracy results were obtained for the three different phrase types.
A Comparison of three Methods of Character Entry on Pen-Based Computers
Authors: MacKenzie I. Scott , Nonnecke R. Blair , McQueen J. Craig , Riddersma Stan , Meltz Malcolm
Published: January 2012

Methods for entering text on pen-based computers were compared with respect to speed, accuracy, and user preference. Fifteen subjects entered text on a digitizing display tablet using three methods: hand printing, QWERTY-tapping, and ABC-tapping. The tapping methods used display-based keyboards, one with a QWERTY layout, the other with two alphabetic rows of 13 characters. ABC-tapping had the lowest error rate (0.6%) but was the slowest entry method (12.9 wpm). It was also the least preferred input method. The QWERTY-tapping condition was the most preferred, the fastest (22.9 wpm), and had a low error rate (1.1%). Although subjects also liked hand printing, it was 41% slower than QWERTY-tapping and had a very high error rate (8.1%). The results suggest that character recognition on pen-based computers must improve to attract walk-up users, and that alternatives such as tapping on a QWERTY soft keyboard are effective input methods.
Safety Considerations in Bicycle Moto-Cross Racing: A Case Study
Authors: Jackson Patricia L. , Cohen H. Harvey
Published: January 2012

This paper presents a case study and literature review on the subject of bicycle moto-cross racing. The case involves a 17 year old male who was severely injured as a result of crashing into a jump during a BMX race. The young man suffered a broken neck and is now a quadriplegic. The paper examines both medical and popular literature on BMX racing and safety. Questions posed include: why no studies have been done to determine the risk of injury in BMX racing; why there are no national databases on BMX injury statistics; and what role the image of BMX in popular magazines plays in promoting or dismissing safety in BMX racing? We found very little information available on the subject of BMX. What information we did locate was inconsistent regarding rules of safety and sportsmanship, risk of injury, and opinion on the safeness of BMX racing. We recommend the following practices as ways to increase safety in the sport: multiple track levels designed for different skill levels; supervised training programs with practice areas for experimenting with new maneuvers; and lessons in tumbling and falling safely to minimize the risk of injuries. We also suggest that studies and databases need to be compiled to consistently evaluate the risk of serious injury in BMX racing.
Risk Perception Issues in the use of Motorized Shoulder Belt/Manual Lap Belt Systems
Authors: Lovvoll David R. , Laughery Kenneth R. , Wogalter Michael S. , Terry Stephanie A.
Published: January 2012

Two experiments employed surveys to address seat belt experience and use as well as perceptions of risk associated with various seat belt configurations. In Experiment 1, a questionnaire was administered to two samples: 104 students at the University of Houston and 162 volunteers at a shopping mall in Raleigh, North Carolina. of primary interest was the use of manual lap belts in motorized shoulder belt systems and reasons for their use or non use. Results showed that compared to manual three point belts, usage rates for manual lap belts in the motorized system were lower. Forgetting and traveling a short distance were frequently cited as reasons for not fastening belts. Estimates of fatalities in a head-on collision scenario indicated lap belts and shoulder belts were perceived to provide equal protection. In Experiment 2, 147 students at the University of Houston completed a follow-up questionnaire. Usage patterns were virtually the same as in Experiment 1. Estimates of likelihood to use lap belts after viewing six different warnings about seat belt use showed warnings containing more explicit hazard information were likely to lead to higher use rates.
Utility Assessment of Side Object Detection Systems for Heavy Trucks
Authors: Mazzae Elizabeth N. , Garrott W. Riley , Cacioppo Anthony J.
Published: January 2012

Side object detection systems (SODS) alert drivers to the presence of traffic alongside their vehicle within a defined detection zone. Their intent is to reduce lane changing and merging collisions. The effect of right SODS on the safety related behavior of commercial vehicle drivers was examined in this study.

Eight subjects drove a tractor-semitrailer equipped with four different sets of right SODS or mirrors. Subjects were tested with two right SODS (a radar-based system, and an ultrasonic-based system), a fender-mounted convex mirror, and, for comparison, standard side view mirrors. For each case, subjects drove the test vehicle through a set route for one day. The effect of these systems on driver behavior and the extent to which safety may be improved by implementing SODS were assessed based upon the correctness of responses and verbal response times to Right Clear questions, and upon subject glance fixations and durations. A debriefing questionnaire was used to acquire subjects' opinions about the SODS.

Driver performance with SODS was not significantly improved over that observed with standard side view mirrors. Analysis of the correctness of responses to Right Clear questions showed that subjects' accuracy in assessing the traffic situation along the right side of the vehicle was not improved by the SODS, but was improved by the fender-mounted convex mirror. Verbal response times to Right Clear questions were significantly lower with the SODS and fender-mounted convex mirror than with standard mirrors. This difference may have resulted from a learning effect caused by presenting the standard mirrors first to each subject. Glance data showed that subjects only sometimes visually sampled the SODS displays. Responses to debriefing questionnaires indicated that subjects were receptive to the concept of SODS and very positive about the fender-mounted convex mirror. However, if SODS are to offer significant safety benefits in the future, more work is needed to refine their performance and design.
On Validation
Authors: Kanis H.
Published: January 2012

In view of the deficient way validation and measurement error are dealt with in Ergonomics/Human Factors research papers, there seems to be much to gain in this multidisciplinary research area. The comparison of practicalities in technical and in social research, which are seen as the main constituents of Ergonomics/Human Factors, elucidates the crucial role that instructions to subjects may play in the emergence of bias as a consequence of the involvement of human beings as part of the research object. Instead of letting validation degenerate into jargon, a framework for measurement criteria is presented. This framework may help to change validation from a defensive ceremony, circling around isolated observations, into a constructive endeavour aimed at general insights into the consequences of human involved research.