Supporting Attention Allocation in Multitask Environments : Effects of Likelihood Alarm Systems on Trust, Behavior, and Performance

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Objective: The aim of the current study was to investigate potential benefits of likelihood alarm systems (LASs) over binary alarm systems (BASs) in a multitask environment. Background: Several problems are associated with the use of BASs, because most of them generate high numbers of false alarms. Operators lose trust in the systems and ignore alarms or cross-check all of them when other information is available. The first behavior harms safety, whereas the latter one reduces productivity. LASs represent an alternative, which is supposed to improve operators’ attention allocation. Method: We investigated LASs and BASs in a dual-task paradigm with and without the possibility to cross-check alerts with raw data information. Participants’ trust in the system, their behavior, and their performance in the alert and the concurrent task were assessed. Results: Reported trust, compliance with alarms, and performance in the alert and the concurrent task were higher for the LAS than for the BAS. The cross-check option led to an increase in alert task performance for both systems and a decrease in concurrent task performance for the BAS, which did not occur in the LAS condition. Conclusion: LASs improve participants’ attention allocation between two different tasks and therefore lead to an increase in alert task and concurrent task performance. The performance maximum is achieved when LAS is combined with a cross-check option for validating alerts with additional information. Application: The use of LASs instead of BASs in safety-related multitask environments has the potential to increase safety and productivity likewise

Complacency and Bias in Human Use of Automation: An Attentional Integration

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Objective: Our aim was to review empirical studies of complacency and bias in human interaction with automated and decision support systems and provide an integrated theoretical model for their explanation. Background: Automation-related complacency and automation bias have typically been considered separately and independently. Methods: Studies on complacency and automation bias were analyzed with respect to the cognitive processes involved. Results: Automation complacency occurs under conditions of multiple-task load, when manual tasks compete with the automated task for the operator’s attention. Automation complacency is found in both naive and expert participants and cannot be overcome with simple practice. Automation bias results in making both omission and commission errors when decision aids are imperfect.Automation bias occurs in both naive and expert participants, cannot be prevented by training or instructions, and can affect decision making in individuals as well as in teams.While automation bias has been conceived of as a special case of decision bias, our analysis suggests that it also depends on attentional processes similar to those involved in automation-related complacency. Conclusion: Complacency and automation bias represent different manifestations of overlapping automation-induced phenomena, with attention playing a central role. An integrated model of complacency and automation bias shows that they result from the dynamic interaction of personal, situational, and automation-related characteristics. Application: The integrated model and attentional synthesis provides a heuristic framework for further research on complacency and automation bias and design options for mitigating such effects in automated and decision support systems

The more the better? The impact of number of stages of likelihood alarm systems on human performance

Responses to alarms involve decisions under uncertainty. Operators do not know if an alarm is more likely to be a hit or a false alarm. Likelihood alarm systems (LAS) help reduce this uncertainty by providing information about the certainty of their output. Unlike traditional binary alarm systems, they have three or more stages: each one represents a different degree of likelihood that a critical event is really present. Consequently, the more stages, the more specific is the information provided by the alarm system to reduce uncertainty. A laboratory experiment with 48 participants was conducted to investigate the effect of specificity of information of LAS on performances and responding behaviour. Specifically, a three-stage, four-stage, and five-stage LAS were compared using a multi-task environment. Results show higher percentages of correct decisions in the alarm task when participants used the four- and five-stage LAS than the three-stage LAS but no significant differences were found between the four-and five-stage LAS. Interesting differences in response patterns were also observed. This study suggests that four stages is the best degree of specificity for optimal performance

Enhancing Spatial Orientation in Novice Pilots: Comparing Different Attitude Indicators Using Synthetic Vision Systems

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Spatial disorientation (SD) is a common factor in aviation accidents, especially in novice pilots. An experiment was carried out to determine which of four different attitude indicator concepts in combination with two different display backgrounds (abstract vs. synthetic landscape) proves to be the most beneficial for novice pilot performance. Inexperienced pilots had to recover from unusual attitudes by using the standard moving-horizon display, a moving-aircraft display, a frequency-separated display, and a “mixed” display, with the latter two representing hybrid concepts with movements of both aircraft symbol and horizon bar. Participants performed the task of recovering from unusual attitudes most efficiently with hybrid display concepts, suggesting that these display concepts prevent figure-ground reversals and associated pilot errors. Outcomes of the study suggest that the implementation of hybrid display concepts as a backup option when unwillingly entering Instrument Flight Conditions could be a solution for preventing SD in novice pilots

Asymmetries in Human Tolerance of Uncertainty in Interaction with Alarm Systems: Effects of Risk Perception or Evidence for a General Commission Bias?

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Providing access towards raw data is often considered to be a good solution for improving human decision making in interaction with imperfect automated decision support such as alarm systems. However, there is some evidence that such cross-checking measures are used in an asymmetric manner with respect to the amount of uncertainty involved in the decision. Namely, people seem to accept low amounts of uncertainty when complying with an alarm cue, but not when contradicting it. The current study investigates the question whether this phenomenon is limited to alarm systems and a high risk environment. Within a multi-task PC simulation participants performed a low risk monitoring task which was supported by a system neutrally framed as “assistant system”. In one group the cues emitted by the system were 90% correct, in the other 10% were correct, thus causing a 10% uncertainty about the real state in both conditions. Results show a strong asymmetry as participants in the latter condition spent a high amount of effort in reducing their uncertainty, while participants in the former condition did not. Furthermore participants’ behavior almost exactly replicates the asymmetric cross-checking pattern found in a former study which employed a comparatively high risk monitoring task supported by an “alarm system”. This supports the hypothesis that the observed commission bias represents a general phenomenon in the context of automated decision support, irrespective of the risk attributed to the environment and irrespective of whether the system represents an alarm system or not

The Impact of a Mnemonic Acronym on Learning and Performing a Procedural Task and Its Resilience Toward Interruptions

The present study examines the potential impact of a mnemonic acronym on the learning, the execution, the resilience toward interruptions, and the mental representation of an eight-step procedural task with sequential constraints. 65 participants were required to learn a sequential task, including eight different steps which had to be carried out in a predefined sequence. 33 participants were provided with the acronym “WORTKLAU” as a mnemonic to support the learning and execution of the task and the other 32 participants had to learn and execute the task without such support. Each letter of the acronym coded one step of the task, involving a binary decision about a certain property of the complex stimulus. In 60 out of 72 trials of the task, participants were interrupted between different steps, and had to perform a 2-back interruption task for 6 or 30 s, after which they had to resume the procedural task as quickly as possible at the correct step. Learning times, performance in uninterrupted trials, and post-interruption performance measures were analyzed. Results of Experiment 1 suggest that the mnemonic acronym enhanced learning of the task sequence, and provide some evidence for a hierarchical mental representation of the task, resulting in faster resumption times at certain steps of the procedure after an interruption. In Experiment 2 the internal structure of the acronym was even emphasized by a hyphen at the borders of the two words included in the acronym (WORT-KLAU). This improved the resilience toward interruptions at the border step of the procedure significantly. Our results provide evidence for beneficial effects of mnemonic acronym particularly for the learning of a sequential procedural task. In addition, they suggest that the structure of mnemonic acronym directly impacts the mental representation of a task. Finally, they show that mnemonic acronyms could be used to improve the resilience toward detrimental effect of interruptions, at least at certain task steps of a procedural task.TU Berlin, Open-Access-Mittel – 201

Is Operators' Compliance with Alarm Systems a Product of Rational Consideration?

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Most theories about operators' responses to alarm systems suggest that the operators' behavior is guided by their trust towards the system which in turn results from the subjective perception of system properties, namely the perceived reliability of the alarm system. However, some doubts about that assumption have arisen as recent research has not proven the mediating effect of trust. The purpose of this research was to examine the relationship between alarm system properties, trust, and behavior. The alarm reliability was varied while keeping the other system properties constant. It was found that participants' response-rates to alarms were predicted by their perceived alarm reliabilities. However, no mediation by trust could be established. These results suggest that operators' behavior is not always guided by their trust towards the system. Under specific circumstances their compliance rather depends on rational consideration regarding the most efficient strategy

Cognitive and psychomotor performance

During space flight, astronauts are exposed to a variety of stressors. Some of these stressors originate from the specific environmental conditions in space (e.g. microgravity, radiation). Others are more unspecific and originate from living and working as member of a small crew in a confined and isolated habitat (e.g. lack of privacy, social monotony). This chapter summarizes our current knowledge about the impact of these space flight-related stressors on cognitive and psychomotor performance of astronauts. It suggests that basic cognitive processes are highly resilient and remain as efficient in space as on Earth. Similarly also processes of spatial imagery and object recognition do not seem to be affected much by the altered conditions in space. In contrast, considerable performance decrements have consistently been observed in different psychomotor tasks. These decrements seem to be caused by microgravity-induced changes of sensorimotor processes, at least during a transient period of primary adaptation to space. The available evidence pointing to impairments of executive functions and higher cognitive processes in space is less conclusive at this time

Human Performance Consequences of Automated Decision Aids in States of Sleep Loss

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Objective: The authors investigated how human performance consequences of automated decision aids are affected by the degree of automation and the operator’s functional state. Background: As research has shown, decision aids may not only improve performance but also lead to new sorts of risks. Whereas knowledge exists about the impact of system characteristics (e.g., reliability) on human performance, little is known about how these performance consequences are moderated by the functional state of operators. Method: Participants performed a simulated supervisory process control task with one of two decision aids providing support for fault identification and management. One session took place during the day, and another one took place during the night after a prolonged waking phase of more than 20 hr. Results: Results showed that decision aids can support humans effectively in maintaining high levels of performance, even in states of sleep loss, with more highly automated aids being more effective than less automated ones. Furthermore, participants suffering from sleep loss were found to be more careful in interaction with the aids, that is, less prone to effects of complacency and automation bias. However, cost effects arose that included a decline in secondary-task performance and an increased risk of return-to-manual performance decrements. Conclusion: Automation support can help protect performance after a period of extended wakefulness. In addition, operators suffering from sleep loss seem to compensate for their impaired functional state by reallocating resources and showing a more attentive behavior toward possible automation failures. Application: Results of this research can inform the design of automation, especially decision aids

Simulatorstudie zur Ermittlung mentaler Handlungsmodelle von Piloten beim Energiemanagement

Im Rahmen des Forschungsprojektes "nxControl" wurde eine Simulatorstudie mit zwölf lizenzierten Verkehrspiloten zur Ermittlung mentaler Handlungsmodelle beim Energieabbau durchgeführt. Die Aufgabe der Piloten war es, drei Sink- und drei Landeanflüge mit variierten Randbedingungen zu absolvieren. Anhand der Versuchsergebnisse sollen Empfehlungen für die pilotenzentrierte Entwicklung eines Assistenzsystems zur Unterstützung der manuellen Steuerung von Flugzeugen in Längsrichtung abgeleitet werden. Die Ergebnisse der Versuche machten es möglich Handlungsstrategien der Piloten für konkrete Handlungsschritte aufzuzeigen. Die Folgerung eines allgemeingültigen Handlungsmodells war auf Grund der differierenden Strategien nicht möglich. Dennoch konnten mit Hilfe der Handlungsstrategien spezifische Fragestellungen beantwortet werden, die für die Entwicklung des Assistenzsystems wertvolle Informationen beinhalteten