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To stand out among the large variations of websites that exist, users should have a good experience. Earlier research found that a good experience influences important user behavior statistics, such as further use of the website. Complexity seems to play a role in the usability of websites and a blockage or delay in reaching the goal leads to negative feelings such as frustration. In this study, FaceReader Online, a tool to measure facial expressions via the internet, was used to measure the effect of the complexity of website design and website tasks on the facial expression anger. Because the expression scores had a low intensity, we calculated a metric for the peak expression. The results indicated that in the more complex tasks the facial expression of anger was higher. These results suggest that the automatically detected facial expression anger could be used to measure usability aspects of a website. [ABSTRACT FROM AUTHOR]

We compared automation monitoring evolution of static or adaptive automation for four different reliability levels over 90 minutes. Previous studies have demonstrated degraded human performance when monitoring automation and that it is possible to mitigate this monitoring performance drop by using adaptive automation. We used the Open Multi-Attribute Task Battery to manipulate two type of automation (static automation without manual take-over sessions and adaptive automation with planned take-over sessions) and four levels of reliability. Participants performed three simultaneous tasks, one of which was automated. Our results suggest that a perfectly reliable or a totally unreliable automation led to different strategies by the participants in terms of visual allocation policy. Under static automation, the time spent looking at the automated task in the 0% reliability level increased over the duration of the experiment; however, the opposite was observed for the 100% reliability level. Although similar, the magnitude of this pattern of results was largely diminished under adaptive automation. For static automation, the reported data also showed a direct link between trust in automation and visual scanning strategies. The more the trust increased, the less the automated task was looked at. [ABSTRACT FROM AUTHOR]

Previous studies have used the Fitts' Law to predict the performance of pointing task on touch screens. It was found that moving distance, target width, and the direction of motion would affect the task performance. The present research aimed to investigate the impact of the initial and terminal positions (ITPs) on pointing performance in two Exps. ITPs were divided into two categories: center of a screen and outer of a screen (center ↔ outer) pointing, and outer of a screen to outer of a screen (outer→outer) pointing. In Exp 1, 30 participants performed the center ↔ outer pointing tasks with 8 directions. The results showed that the outer → center movement was significantly faster than the center → outer at 45°, 90°, and 180°. In Exp 2, 30 participants performed the outer → outer pointing tasks with eight directions. The current study revealed that the ITPs influenced the performance of the pointing task, possibly due to human biomechanical characteristics associated with different movements. [ABSTRACT FROM AUTHOR]

Managing work quality has been an important issue for designing crowdsourcing tasks. Previous studies have proposed a number of ways to improve work quality, such as providing financial incentives, filtering random clickers, or designing workflow patterns. However, the potential benefit of having communication between the task owner and workers has been under-explored. This paper examined the effects of feedback and goal-setting messages on output quality in a crowdsourcing environment. The results revealed that negative and evaluative feedback and distal+proximal and achievement goal-setting messages improved output quality in shortening the volume, time, and cost to complete. The amount of monetary reward was found to have little to mixed influence over work quality, which meant more money did not lead to the higher work quality. Instead, the size of the reward must be paired with the appropriate type of messages for overall quality improvement. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of non-driving-related tasks (NDRTs) on takeover quality in the context of automated driving. Specifically, we examined the effects of three categories of NDRT attributes (i.e., physical, cognitive, and visual) on longitudinal and lateral driving measures when the drivers resumed control. We designed a driving simulator study where the participants experienced automated driving journeys and takeover situations. When the automated mode was activated, drivers engaged in one of the nine NDRTs. The results showed that the cognitive load of NDRTs had a significant negative correlation with both longitudinal and lateral control measures. However, the effects of two attributes in the physical category and one attribute in the visual category on driving performance did not show statistical significance. Overall, the findings indicated that the influence of cognitive attributes on takeover quality is more salient than that of the physical and visual attributes, which provides insights into the understanding of takeover situations to improve driving safety. [ABSTRACT FROM AUTHOR]

System dialog messages are often troublesome for mobile users. In this study, behavioral experiments were conducted on 18 younger (age; 24.7 ± 1.7) and 18 older (63.8 ± 2.0) age groups using mobile devices. In the experiment, system dialog messages were popped up on a smartphone as an interruption in the task switching process, and which attributes of the dialog messages (the amount of jargon and length of the message) significantly affected the performance of the whole task switching process was observed. The results showed that the younger participants did not show significant differences in their task switching performance according to the attributes of the dialog message. However, the older participants showed increased task performance time for the interruption task with extensive jargon. Furthermore, the older participants also revealed difficulty transferring information as they resumed the primary task just after processing the interrupting dialog messages, suggested by correlations between temporal and subjective workload responses. Based on the analysis results, we proposed some guidelines to design system dialog messages for older mobile device users. [ABSTRACT FROM AUTHOR]

Multi-device use has become a popular pattern of device use in recent years. However, empirical studies pertaining to motivations behind intention to use multiple devices have been limited. The objective of this study focuses on answering an essential question: given that heterogeneous devices are available to users, why do users use multiple devices rather than a single device to complete a task? Both Task-Technology Fit Theory and mental workload paradigm are considered to develop eight hypotheses and build the research framework. A trip-planning scenario was designed and used in the questionnaire to understand the factors that motivate users to use multiple devices. A total of 217 subjects completed the questionnaire. The results show that perceived task fit with multi-device use forms users' attitudes toward and expected satisfaction with multi-device use. Furthermore, users' attitudes toward multi-device use trigger their intentions to use multiple devices. Additionally, perceived complexity of multi-device use hinders users from perceiving good task fit with multi-device use. Implications for theory, practice, and future research directions are discussed. [ABSTRACT FROM AUTHOR]

In training, task proficiency is typically assessed through relevant performance measures. Such measures provide information about how effectively the individual can perform the task, but they give no insight about cognitive efficiency. Neural signals may provide this information regarding a trainee's task proficiency that performance measures alone cannot. The purpose of this study was to investigate patterns in neural activity that are indicative of task proficiency. Ten novice participants completed ten trials of a maneuvering task in a lifeboat simulator while their neural activity was recorded via electroencephalography (EEG). Power spectral features were used along with linear discriminant analysis to classify the data from pairs of adjacent trials. Repeated measures mixed model linear regression showed that, on average, the accuracy with which adjacent trials could be discriminated from each other decreased significantly over the course of training. The result indicates that with practice, the associated neural activity becomes more similar from trial to trial. [ABSTRACT FROM AUTHOR]

Insufficient effort has been made to investigate details of the diagnostic process, specifically information seeking and information integration. In this study, participants were asked to accomplish eight diagnostic tasks of locating the leaking position of some working material in a simulated nuclear power plant. The participants' information seeking actions and possibility judgments about all potential leaking positions were recorded and then described using eight dependent variables concerning their gains and expenses. Generalized linear mixed-models were used to evaluate the effects of time pressure and the correlations. The results showed that (1) information seeking and information integration were closely correlated in multifaceted ways; (2) higher diagnostic accuracy was associated with fewer information acquiring actions but with longer average intervals between these actions; and (3) high time-pressure induced speed-and-accuracy trade-offs in the sub-processes, and the overall diagnostic speed and accuracy were negatively related between individuals, but positively related between trials [ABSTRACT FROM AUTHOR]

Diagnostic accuracy can be life-critical or safety-critical, and it is of preventive interests to predict human performance on diagnostic tasks beforehand. This study conducted an experiment to select competent predictors to account for between-individual, between-task, and between-trial differences of various performance facets of human diagnostic processes. In the experiment, participants were required to diagnose a novel accident in a simulated nuclear power plant. Eight dependent variables were used to describe their information seeking, information integration, and overall process of diagnosis. The results identified the closeness of an individual's mental model to that of an expert and the steps that an optimal algorithm took to solve a diagnostic task as individual- and task-predictors, respectively. Trial number was found to account for the practice effects. Competency and incompetency of various predictors were discussed, and consequential recommendations were provided. [ABSTRACT FROM AUTHOR]

The effectiveness of banner advertisements has gained considerable attention among academics and practitioners. Despite the research progress in investigating the effect of banner properties (e.g., animation and location) on user perception and behavior, there is still a very limited understanding of how the properties of a banner and the surroundings of a website on which a banner is displayed can jointly influence its effectiveness. This study used eye-tracking technology to investigate the impact of banner animation and webpage complexity on users' attention and memory performance. The results show that, during a free browsing task, an animated banner can attract earlier, greater, and more frequent attention from users and lead to better memory performance than a static one. Similarly, a banner on a low-complexity webpage also attracts earlier and more frequent attention among users and results in better memory performance than that on a high-complexity webpage. One implication is that an animated banner or a banner on a low-complexity webpage can provide a promising means of attracting users' attention and enhancing their memory of the banners. Moreover, this study finds an interaction effect between banner animation and webpage complexity on the time to first fixation on a banner, but not on the total numbers or duration of fixations on a banner, or users' memory performance. The finding highlights that an animated banner on a low-complexity website can be the most effective means to shorten the time to first fixation and quickly attract users' attention. However, it cannot be deemed the most effective in generating greater and more frequent fixations on a banner, or leading to superior user memory performance. [ABSTRACT FROM AUTHOR]

Sensing the intention of a user’s forthcoming action is a necessary function for systems that assist human physical activity. In this article, a strategy for recipe guidance systems that can predict the forthcoming intended subtask in a cooking task is investigated. The focus is on user accessing objects, that is, touching and releasing objects. Touching can indicate the start of the forthcoming subtask and releasing can indicate the end of the task. The main difficulty lies in the fact that humans may move objects because they are in the way and use cooking tools that are unanticipated by an assistive system. In such cases, the accessed object should not indicate the forthcoming subtask. A method is proposed to track the progress of a task based on the object access history. This enables to eliminate object accesses that are out of context. Simultaneously, the method predicts the forthcoming subtask based on a combination of progress and materials rather than tools and materials. Then, a guidance system that runs as a web service is developed. In experiments, real cooking activities navigated by this system are observed. The Wizard of OZ method is utilized to simulate a system that detects object accesses. The experimental results show that 73.6% accuracy is achieved in the selection of the displayed information. This result supports the use of “access to objects” realize effective intention-sensing systems. [ABSTRACT FROM AUTHOR]

The potential benefits of thumb-based touch interaction have not been fully exploited due to its usability problems and performance deterioration. Despite the well-known problems, mobile phone users often prefer thumb-based input method in their daily context of use. Without understanding input performance under realistic variability, design solutions may not address the problems adequately. This research aims to evaluate performance of one-handed thumb-based input compared to cradled finger-based input for the large number of users and varying task conditions. By investigating performance under a range of user- and task-variability, common patterns can be identified to help infer realistic performance in context of use. For this experiment, 259 participants were recruited balanced on gender and age. They performed user testing of moving an icon on a mobile touch-screen. Overall, the one-handed thumb input showed a 30% reduction in throughput compared to the cradled finger-based input, with significant reduction in speed and accuracy. Reduced throughput is attributed to inaccuracy rather than speed. In addition, the partial effects of touch position, dragging direction, and target size were investigated and quantified. In conclusion, performance could maintain constant throughput only for the finger-based input of limited task conditions, when realistic variability was introduced. Also, high variance of throughput for the thumb-based input led to poor conformity to Fitts’s law. The findings have implications for design of thumb-based touch interface to offset performance reduction and characterizing performance measure for thumb-based input method. [ABSTRACT FROM AUTHOR]