Showing papers in "International Journal of Cognitive Ergonomics in 2001"
TL;DR: A constrained review of human factors issues relevant to adaptive automation, including designing complex system interfaces to support AA, facilitating human–computer interaction and crew interactions in adaptive system operations, and considering workload associated with AA management in the design of human roles in adaptive systems are presented.
Abstract: This article presents a constrained review of human factors issues relevant to adaptive automation (AA), including designing complex system interfaces to support AA, facilitating human–computer interaction and crew interactions in adaptive system operations, and considering workload associated with AA management in the design of human roles in adaptive systems. Unfortunately, these issues have received limited attention in earlier reviews of AA. This work is aimed at supporting a general theory of human-centered automation advocating humans as active information processors in complex system control loops to support situation awareness and effective performance. The review demonstrates the need for research into user-centered design of dynamic displays in adaptive systems. It also points to the need for discretion in designing transparent interfaces to facilitate human awareness of modes of automated systems. Finally, the review identifies the need to consider critical human–human interactions in designing adaptive systems. This work describes important branches of a developing framework of AA research and contributes to the general theory of human-centered automation.
148 citations
TL;DR: In this article, the authors evaluated methods for eliciting and assessing team knowledge during acquisition of a complex task and evaluated their ability to predict team performance and also in terms of how they reflect skill acquisition.
Abstract: The design of team training programs and other team interventions could benefit from an understanding of team cognition The research presented in this article evaluates methods for eliciting and assessing team knowledge during acquisition of a complex task Knowledge measures are evaluated in terms of their ability to predict team performance and also in terms of how they reflect skill acquisition The study was conducted in the context of a synthetic 3-person team task that involved operating an uninhabited air vehicle (UAV) Eleven teams of 3 Air Force ROTC cadets participated in 3 experimental sessions lasting from 3 to 6 hr During these sessions, teams were trained on the task and were observed as they performed ten 40-min missions During the missions, team performance and team process behaviors were measured, as well as the fleeting team knowledge associated with situation awareness In addition, long-term team knowledge regarding both taskwork and teamwork were measured offline in four sessions
125 citations
TL;DR: In this paper, the authors considered the effects of automating driver's control tasks, and compared four levels of automation: manual, adaptive cruise control (ACC), active steering (AS), adaptive steering, and active steering plus AS.
Abstract: The research reported in this article considers the effects of automating driver's control tasks. Driving can be broken down into 3 general subtasks: navigation, control, and hazard avoidance. Control can be further subdivided into lateral control (position in lane) and longitudinal control (speed and leading headway). Lateral control can be automated by an active steering (AS) system, and longitudinal control can be automated by an adaptive cruise control (ACC) system. Previous research has used driving simulators to consider the effects of driver workload and the ability to reclaim control with these systems. There are, however, some questions about the validity of driving simulators, and this research sought to validate a driving simulator. This was achieved by comparing responses on a secondary task and driving style questionnaire in both a road car and a driving simulator. When validity was established, a comparison of 4 levels of automation was undertaken: manual, ACC, AS, and ACC plus AS. The resul...
93 citations
TL;DR: The criterion validity of the NASA Task Load indeX (TLX) and a previously developed subjective Task Complexity Index (TCI) were studied and indicated stronger criterion validity for the subjective task complexity measure than for the TLX.
Abstract: The criterion validity of the NASA Task Load indeX (TLX) and a previously developed subjective Task Complexity Index (TCI) were studied. A measure of subjective task complexity was hypothesized to complement the NASA TLX subjective workload measure on prediction of performance on complex problem-solving tasks. Twelve licensed nuclear power plant operators participated in a study with 16 simulated realistic scenarios. Although the study indicated some validity for both the TLX and the TCI, the results indicated stronger criterion validity for the subjective task complexity measure than for the TLX. Factor analysis of the task complexity ratings and TLX ratings together indicated that the 2 measures represent different constructs. Implications of the research include the recommendation of assessing subjective task complexity when studying human-machine configurations dealing with complex problem-solving tasks.
75 citations
TL;DR: The findings show that users' knowledge structures do depend on the nature of the graphical information presented at the interface but do not rely as much on the use of the visual metaphor as previously thought.
Abstract: Research has shown that individuals' knowledge structures change as a result of learning and experience. This article investigates the possibility that the content of graphical user interfaces can play a role in determining the nature of the knowledge structures users develop. Users employed either concrete, abstract, or arbitrary icon sets in a computer-based problem-solving task. The effects of these icons were assessed using standard measures of performance. On the basis of the assumption that users' mental models should be better if appropriate icons were presented on the interface, Pathfinder analysis was used to elicit users' knowledge structures as they gained experience with the interface. The efficacy of this measure was then compared with performance measures. Our findings show that users' knowledge structures do depend on the nature of the graphical information presented at the interface but do not rely as much on the use of the visual metaphor as previously thought. Although most measures were...
62 citations
TL;DR: The work reported here begins to address this gap by directly comparing the information requirements produced by what are probably the 2 most commonly used analysis techniques-Rasmussen's (1985) Abstraction-Decomposition Space (ADS) or "Abstraction Hierarchy" and Shepherd's (1989) Hierarchical Task Analysis (HTA) technique.
Abstract: Cognitive work analysis (CWA) techniques are the primary methods available for designers to obtain the knowledge required to create interfaces to complex systems involving cognitive work. There are a wide and growing variety of analysis methods available with a variety of claims for their relative strengths and weaknesses, but it is extremely rare for anyone actually to apply different analytic techniques to the same analysis problem. The work reported here begins to address this gap by directly comparing the information requirements produced by what are probably the 2 most commonly used analysis techniques-Rasmussen's (1985) Abstraction-Decomposition Space (ADS) or "Abstraction Hierarchy" and Shepherd's (1989) Hierarchical Task Analysis (HTA) technique. These 2 approaches were selected because each is well known in the literature, yet they rarely have been directly compared on a common problem. Our comparison shows that the techniques produce different yet complementary information about the interaction ...
55 citations
TL;DR: In this article, the authors test the COtext and COntrol Model (COCOM) developed by Hollnagel (1993) and show that the team behavior can be reliably categorized into four control modes and this provided a useful way of distinguishing between experimental conditions.
Abstract: This article sets out to test the hypothetical COtext and COntrol Model (COCOM) developed by Hollnagel (1993). Essentially, Hollnagel develops the argument that team behavior should be analyzed at a macro, rather than micro, level. He proposes 4 principal models of team activity: strategic, tactical, opportunistic, and scrambled. These modes of team behavior vary in terms of the degree of forward planning (highest in the strategic mode) and reactivity to the environment (highest in the scrambled mode). He further hypothesizes a linear progression through the modes from strategic to tactical to opportunistic to scrambled, depending on context, and vice versa. To test the COCOM model, we placed teams of people in a simulated energy distribution system. Our results confirm Hollnagel's hypothesized model in 2 main ways. First, we show that the team behavior could be categorized reliably into the 4 control modes and this provided a useful way of distinguishing between experimental conditions. Second, the progr...
49 citations
TL;DR: An important principle of activity theory is the unity of cognition and behavior as discussed by the authors, which is the principle of unity between cognition and behaviour. But much data in this area remains unknown to the English-speaking world.
Abstract: Activity theory has an extensive history in the Soviet Union dating back to the works of Vygotsky and his followers. Activity (or "deyatel'nost" in Russian) refers to a coherent system of internal mental processes and external behaviors and motivations that are combined and organized by the mechanisms of self-regulation to achieve a conscious goal. Activity theory is emerging as a new paradigm for psychology and an interdisciplinary approach to human sciences in Europe. Furthermore, scientists are writing about the internationalization of this approach. For example, activity theory exerted a great influence on the development of ACTION THEORY in Germany. In the United States, activity theory is associated with the sociocultural approach initiated by Vygotsky. However much data in this area remains unknown to the English-speaking world. This article introduces and discusses an important principle of Activity theory, that is, "the principle of unity of cognition and behavior." Because this principle is impo...
40 citations
TL;DR: The Abstraction Hierarchy, Multilevel Flow Modeling, and the Decision Ladder are discussed, which create a model of the work domain structure, MFM of work domain goals, and DL of actor tasks.
Abstract: Model-based approaches to cognitive task analysis rely on abstracting from the problem domain, rather than a description of task performance. Various classes of work analysis models can be distinguished: task models, work domain structure models, and work domain goal models. In this article, we discuss 3 specific model-based approaches: the Abstraction Hierarchy (AH), Multilevel Flow Modeling (MFM), and the Decision Ladder (DL). The AH creates a model of the work domain structure, MFM of work domain goals, and DL of actor tasks. The 3 approaches are compared in the context of a common example-that of a power plant boiler-to show clearly the differences among the 3 classes of techniques.
29 citations
TL;DR: In this paper, the authors examined the processes followed to recover from failures and found that three main types of recovery actions exist: failure or problem detection, explanation of the causes, and corrective actions.
Abstract: The prevention of errors and other failures has always been a central theme in safety and reliability management. However, additional benefits could be gained from focusing on what can be done after a failure has occurred, before it leads to negative consequences. This article examines the processes followed to recover from failures. Incident and near-miss data collected in an exploratory case study at a chemical process plant indicate, in agreement with literature survey findings, that 3 main types of recovery actions exist. These action types correspond with the phases recovery processes go through: actions aimed at failure or problem detection, actions aimed at explanation of the causes, and corrective actions. The data also show that the explanation and correction phases can be repeated and do not necessarily occur in that order. Finally, the results clearly demonstrate the essential role of the human operator for each of the recovery process phases.
29 citations
TL;DR: In this paper, the authors examined participant's accuracy in reproducing triadic representations of objects, having learned them previously under 1 of 3 different conditions: active exploration, passive exploration, and static view of a map.
Abstract: Virtual environments (VE) promise important opportunities as future interfaces to computational systems, especially where such technology can take advantage of strong human visuospatial capabilities. Although such synthetic environments often project homeomorphic physical representations of real-world layouts, it is not known how individuals develop representational models to match these environments. To evaluate this process, this experiment examined participant's accuracy in reproducing triadic representations of objects, having learned them previously under 1 of 3 different conditions. The layout consisted of 9 common objects arranged on a flat plane. These objects could be viewed in a free VE, a static VE, or from the static view of a map. The first condition allowed active exploration of the environment while the latter two conditions allowed the participant only a passive opportunity to observe from a single viewpoint. Viewing conditions were a between-subject variable with seven participants random...
TL;DR: An object-oriented methodology is described that implements the blackboard model within a realistic task context and an existing implementation in a real-time human-in-the-loop simulation is described to demonstrate the utility of time windows.
Abstract: A proper understanding of human performance characteristics is a prerequisite for designers of complex systems. Although human factors texts provide some insights into basic performance issues, the emergence of highly automated computing systems have fundamentally altered the way humans work. The purpose of this article is to present a research approach to quantify and analyze human performance within a complex, time-critical system. The approach is centered on a measurement construct, called a time window, which enables a functional relation between constraints on operator activities and time availability. A blackboard model is developed as the mechanism to generate, maintain, and complete time windows. Moreover, an object-oriented methodology is described that implements the blackboard model within a realistic task context. To demonstrate the utility of time windows, an existing implementation in a real-time human-in-the-loop simulation is also described. Using time window outcomes, some cursory analyse...
TL;DR: In this paper, the effects of vehicle feedback on driver cognition were investigated using a concurrent verbal protocol, where 12 drivers drove their own cars around a predetermined 14 mile test route, and the vehicles were divided into two groups according to their mechanical and engineering specifications into high and low vehicle feedback status.
Abstract: A proposed feedback model of driving implicates vehicle feedback as an important variable affecting driver cognition. This naturalistic study employs an on-road paradigm to begin investigating the effects of vehicle feedback on drivers. Whilst performing a specially designed concurrent verbal protocol, 12 drivers drove their own cars around a predetermined 14 mile test route. This was designed to elicit the information that drivers were gaining from the environment and the vehicle, and how this information was being put to use. Prerun questionnaire measures featured driving style and locus of control, whereas postrun measures included self-assessment of mental workload and situational awareness. The vehicles were divided into 2 groups contingent upon their mechanical and engineering specifications into high and low vehicle feedback status, anecdotally, driver's cars versus average cars. A content analysis showed key differences in driver cognition contingent upon the vehicles feedback status. High-feedbac...
TL;DR: This study studied the effects of frame layout and background contrast on visual search performance using a 2 x 4 mixed measures experimental design, and found an effect of layout both on accuracy and speed measures.
Abstract: One of the most important determinants of the success of Web sites is their degree of usability. This study aims to contribute toward Web design guidelines for usability through an empirical investigation into 2 Web page design parameters. Using a 2 x 4 mixed measures experimental design, we studied the effects of frame layout and background contrast on visual search performance. Using mock Web pages, 154 undergraduates carried out a visual search task. Analysis showed an effect of layout both on accuracy and speed measures, with frames located at the top of the screen leading to better performance. No main effect of contrast was found, although there was an interaction between layout and contrast in reaction time for hits. Preference for frame layout was dependent on background contrast. The results are discussed in terms of visual search processes, and design recommendations are given.
TL;DR: Alarms are potentially a rich source of information that can be used in all phases of responding to a disturbance and should therefore be considered as an aspect of the general process information.
Abstract: The use of alarms in process control is a complex affair, because alarms can have many different functions over and above that of alerting the operator to a new event. Alarms are potentially a rich source of information that can be used in all phases of responding to a disturbance and should therefore be considered as an aspect of the general process information. From the point of view of cognitive systems engineering, alarms provide information that enables the operators to maintain control of the process and to be proactive as well as reactive. An important issue is the time and effort needed to evaluate events and new information (time to evaluate: TE) and the time and effort needed to select an appropriate response or line of action (time to select: TS). The former (TE) can be supported by more effective presentation of information, specifically a more comprehensive presentation of alarms. The latter (TS) can be supported by various kinds of computerized support, ranging from planning systems to adapt...
TL;DR: An example application of the UE method resulted in a prototype user interface with the online procedures integrated into the operation display, and with consistent navigation support in procedure and operation interface components.
Abstract: A usability engineering (UE) method has been developed for the European Space Agency to assist the development teams of payload user interfaces in the International Space Station (ISS). It attempts to synchronize the activities of 2 traditionally separated groups-the operations group involved in procedure development and the software group involved in display development-to realize adequate online procedural operation support (instead of the traditional paper-based support). An example application of the UE method resulted in a prototype user interface with the online procedures integrated into the operation display, and with consistent navigation support in procedure and operation interface components. A controlled experiment showed that the integration and the navigation support enhance the efficiency of payload operations substantially as a first validation of this example interface design.
TL;DR: This work created 3 alternative presentations of the SFO and WOS information using the mental representations of experienced wildland firefighters and evaluated how well novice participants could remember the information when presented with 1 of these alternatives or the current presentation format.
Abstract: The Standard Fire Orders (SFO) and Watch-Out Situations (WOS) provide wildland firefighters with the essential information needed for safe and efficient operation. Although fundamental, the information is difficult to remember because it fails to capitalize on its inherent relatedness and inappropriately applies mnemonic techniques. We created 3 alternative presentations of the SFO and WOS information using the mental representations of experienced wildland firefighters. We then evaluated how well novice participants could remember the information when presented with 1 of these alternatives or the current presentation format. Data revealed the lowest recall rates for the current format of the SFO and WOS and the highest for the more concise alternatives. Possible methods for the development of information systems are discussed.
TL;DR: The results illustrated that operating a modern single-grip harvester causes relatively high mental workload.
Abstract: In this case study, operators' cardiovascular activity was observed during the operation of modern forestry machinery. In addition to heart rate, power spectral analysis was used to indicate how the variance distributes as a function of frequency. As has been pointed out in previous studies, changes in relative power, especially at medium frequencies (MF), have been found to indicate the amount of mental workload. The results illustrated that operating a modern single-grip harvester causes relatively high mental workload. Moreover, significant differences in cardiovascular activity during different work tasks were observed.
TL;DR: Drivers' characteristics in the perception of a lead vehicle's deceleration level were investigated in the laboratory using film clips made from a vehicle following another vehicle in a car-following situation and a magnitude estimation method was used and the relation between the perceived and the actual de acceleration level was expressed in terms of Stevens' power law.
Abstract: Drivers' characteristics in the perception of a lead vehicle's deceleration level were investigated in the laboratory using film clips made from a vehicle following another vehicle in a car-following situation. To construct a scale of the perceived deceleration level, a magnitude estimation method was used and the relation between the perceived and the actual deceleration level was expressed in terms of Stevens' power law. The results showed that the drivers generally underestimated the lead vehicle's deceleration level and as the deceleration level increased, so did the amount of underestimation. The relation between the perceived and the actual deceleration level fitted to Stevens' power law very well (r2 =. 997), having the exponent of. 648. Finally, the visual cues used in perceiving the deceleration level of the lead vehicle and the devices that can aid the drivers are discussed.
TL;DR: A hierarchical task analysis is presented as a methodological framework for looking at the process of analytical measurement, followed by an account of the potential errors that can occur.
Abstract: Analytical measurement, the process by which the chemical composition of a substance is determined, is carried out in chemical laboratories throughout the world. It has been recognized for some time that results obtained from different laboratories are not as consistent as would be expected, but until recently little attention has been paid to the human factors and human error aspects of the task. However, analytical measurement is a multistage task that places high manual and cognitive demands on the operator, which are likely to be the source of considerable human error, as it is likely that the reliability of the task could be improved by the application of appropriate cognitive ergonomics. Task demands range from accuracy in manual, skill-based activities to complex, knowledge-based activities. This paper presents a hierarchical task analysis as a methodological framework for looking at the process of analytical measurement, followed by an account of the potential errors that can occur. These errors a...
TL;DR: Sharable instructional objects are likely to reduce the costs and increase the effectiveness of both ADL technologies and ITS, and development of these objects should be cooperatively shared.
Abstract: By reviewing data on classroom and tutorial instruction, this article presents a perspective on the value of technology-based instruction in general and intelligent tutoring systems (ITS) in particular. It finds mixed-initiative dialogue and on-demand, real-time generative capabilities to be defining functionalities of ITS. These functionalities are motivated by basic research into human learning and cognition. From this perspective, development of both the Advanced Distributed Learning (ADL) initiative and ITS are viewed as parallel but presently independent activities. Their common interests in the development and availability on the World Wide Web of sharable (accessible, interoperable, durable, and reusable) instructional objects that can act as either instructional content or algorithmic agents are described and discussed. Sharable instructional objects are likely to reduce the costs and increase the effectiveness of both ADL technologies and ITS. Development of these objects should be cooperatively ...
TL;DR: The results indicated that all 3 environmental characteristics affected acquisition of route knowledge, and can be applied to the design of virtual environments and navigational aids that facilitate acquisition ofroute knowledge in the environment.
Abstract: A virtual environment was constructed to permit the investigation of the effects of changes in elevation, route distance, and route complexity on the acquisition of route knowledge in the environment. The environment contained 14 rooms distributed across the 2-story virtual environment. Thirty college students learned the location of the rooms through a repeated series of navigation tasks. The results indicated that all 3 environmental characteristics affected acquisition of route knowledge. Participants appeared to learn the room location based on route distance and complexity first and learned the correct elevation of the room last. The findings of this study can be applied to the design of virtual environments and navigational aids that facilitate acquisition of route knowledge in the environment.
TL;DR: A conceptual framework of decisionMaking is suggested to distinguish between dynamic and static decision making and the inadequacy of static reasoning models in handling dynamic decision making is discussed.
Abstract: Because of substantial advances of automatic technology in human-machine systems, the operator has changed to a "decision maker" in a control room. Modeling operator's decision behavior has attracted a major interest in research fields such as human factors and reliability engineering. However, traditional reasoning models proposed by psychologists are "static" so that they are deficient in accounting for the interactive nature of modern human-machine systems. Concerning this issue, a conceptual framework of decision making is suggested to distinguish between dynamic and static decision making. Hence, dynamic and static decision processes are defined considering the decision stages in a decision-making task. Reasoning is regarded as a dominant mental activity in each decision stage and the inadequacy of static reasoning models in handling dynamic decision making is discussed. Considering human cognitive biases and the requirements of engineering applications, an event-driven approach, called the Dynamic B...
TL;DR: A communication architecture based on microprotocols that adapt so as to maintain user perception even as the quality of the multimedia presentation degrades due to network congestion is presented.
Abstract: When viewing a multimedia document on the web, 2 parameters comprise the user perception of the document: user satisfaction/enjoyment of the document and user assimilation/understanding of the information contained in the document. Existing communication architectures and protocols do not cater to the user's experience with multimedia. In this article we present a communication architecture based on microprotocols that adapt so as to maintain user perception even as the quality of the multimedia presentation degrades due to network congestion. We compare our protocols with 2 legacy protocols by testing real users for perception as the quality of the multimedia presentation deteriorates. Our results show that despite the overheads for adaptation, our protocol performed the best from a user's perspective. Our research shows that not only is it desirable but feasible to tailor communication architectures and protocols to the benefit of the user.
TL;DR: The authors reviewed Situation Awareness Analysis and Measurement, edited by Mica R. Endsley and Daniel J. Garland, with a review of situation awareness analysis and measurement, and concluded:
Abstract: (2001). Book review of Situation Awareness Analysis and Measurement, edited by Mica R. Endsley and Daniel J. Garland. International Journal of Cognitive Ergonomics: Vol. 5, No. 2, pp. 181-182.
TL;DR: The results suggest that the movement of objects and the information presentation refresh rates in a display environment are important variables to consider in visual cognition studies.
Abstract: Experiments were conducted to examine whether information refresh rate and moving objects have an effect on saccade latency times The ratio of the number of moving objects to the number of static objects in a display was used to define dynamic object ratio (DOR), an independent variable in the study The results of the experiment reveal the following: (a) dynamicity and information refresh rates have effects on saccade latency; (b) it was observed that when DOR increases, participants took longer time to make their initial saccades; and (c) as the DOR increases beyond 2 dynamic objects, latency times seem to be the same irrespective of the information refresh rate The results suggest that the movement of objects and the information presentation refresh rates in a display environment are important variables to consider in visual cognition studies We hope to expand the experiment to include effects on visuospatial attention, information recall, and information contents to be analyzed by human participants