Using task analysis to improve usability of fatigue modelling software

The design of any interactive computer system requires consideration of both humans and machines. Software usability is one aspect of human–computer interaction that can benefit from knowledge of the user and their tasks. One set of methods for determining whether an application enables users to achieve their predetermined goals effectively and efficiently is task analysis. In the present study, a task analysis was applied to the graphical user interface of fatigue modelling software used in industry. The task analysis procedure allowed areas of usability improvement to be identified and then addressed with alternate interface prototypes. The present method of task analysis illustrates a practical and efficient way for software designers to improve software usability, user effectiveness and satisfaction, by involving users in the design process.     

The importance of interface complexity and entropy for online information sharing

In this paper, we describe two experiments that show the powerful influence of interface complexity and entropy on online information-sharing behaviour. One hundred and thirty-four participants were asked to do a creativity test and answer six open questions against three different screen backgrounds of increasing complexity. Our data show that, as an interface becomes more complex and has more entropy users refer less to themselves and show less information-sharing breadth. However, their verbal creativity and information-sharing depth do not suffer in the same way. Instead, an inverse U-shaped relationship between interface complexity and creativity as well as information-sharing depth can be observed: users become more creative and thoughtful until a certain tipping point of interface complexity is reached. At that point, creativity and thinking suffer, leading to significantly less disclosure. This result challenges the general HCI assumption that simplicity is always best for computers’ interface design, as users’ creativity and information-sharing depth initially increases with more interface complexity. Our results suggest that the Yerkes–Dodson Law may be a key theory underlying online creativity and depth of online disclosures.     

Changes in perceived usability and aesthetics with repetitive use in the first use session

This study examines how repetitive use in a short time period influences perceived usability, aesthetics, and user satisfaction. A mixed design was used, considering usability, aesthetics, and exposure time. Sixty‐four users were tested in a controlled experimental setting. According to the results, the negative effect of low usability on perceived usability and user satisfaction decreased as familiarity with the tasks increased. Also, the negative effect of low aesthetics on perceived usability weakened with repetitive use. These results imply that repetitive use can be an important matter for products with bad designs and promoting repetitive use in a short time period can be an effective strategy to reduce negative user perceptions.     

The role of context in perceptions of the aesthetics of web pages over time

An important aspect of the empirical study of user experience is the process by which users form aesthetic and other judgements of interactive products. The current study extends previous research by presenting test users with a context (mode of use) in which to make their judgements, using sets of web pages from specific domains rather than unrelated pages, studying the congruence of perceptions of aesthetic value over time, including judgements after use of a web site, manipulating the aesthetic design of web pages and studying the relationship between usability and aesthetic value. The results from two experiments demonstrate that context increases the stability of judgements from perceptions after brief exposure to those after self-paced exposure and from perceptions after self-paced exposure to those of after site use. Experiment 1 shows that relatively attractive pages are preferred over relatively unattractive pages after brief exposure, but only if no context is provided. Experiment 2 shows that after brief exposure, classically aesthetic pages that are information oriented are rated as more attractive than expressively aesthetic pages. Perceptions are not correlated with measures of task performance or mental effort. We conclude that context is a pivotal factor influencing the stability of users’ perceptions, which must be explicitly addressed in the study of users’ product experience. Furthermore, the type of aesthetics that is relevant to users’ perceptions appears to depend on the application domain. The principle ‘what is beautiful is usable’ is not confirmed.     

Permissive user interfaces

User interfaces often only support one way to do a task when the physical interface or the requirements of the task would permit other ways. In contrast, a user interface that supports multiple approaches is permissive. This paper argues that permissive user interfaces are easier to use—and even when they are not applicable for particular applications, considering permissiveness is a productive design heuristic.Many user interfaces are difficult to use yet very easily demonstrated or explained by experts—with the results that users become frustrated because hindsight makes usability problems look like the user's own fault. The lack of permissiveness in such user interfaces explains this paradox.     

A parallel coordinates style interface for exploratory volume visualization

We present a user interface, based on parallel coordinates, that facilitates exploration of volume data. By explicitly representing the visualization parameter space, the interface provides an overview of rendering options and enables users to easily explore different parameters. Rendered images are stored in an integrated history bar that facilitates backtracking to previous visualization options. Initial usability testing showed clear agreement between users and experts of various backgrounds (usability, graphic design, volume visualization, and medical physics) that the proposed user interface is a valuable data exploration tool.     

Facets of simplicity for the smartphone interface: A structural model

Motivated by the need to develop an integrated measure of simplicity perception for a smartphone user interface, our research incorporated visual aesthetics, information design, and task complexity into an extended construct of simplicity. Drawn from three distinct domains of human–computer interaction design and related areas, the new development of a simplicity construct and measurement scales were then validated. The final measurement model consisted of six components: reduction, organization, component complexity, coordinative complexity, dynamic complexity, and visual aesthetics. The following phase aimed at verifying the relationship between simplicity perception of the interface and evaluations of user satisfaction. The hypothesis was accepted that user satisfaction was positively affected by simplicity perception and that the relationship between the two constructs was very strong. The findings imply that a simplified interface design of the task performance, information hierarchy, and visual display attributes contributes to positive satisfaction evaluations when users interact with their smartphone as they engage in communication, information search, and entertainment activities.     

The influence of product aesthetics and user state in usability testing

An empirical study examined the effects of two influencing factors in usability tests on user performance and usability ratings. Product aesthetics (high vs. low) as the main independent factor and prior usage event (positive vs. negative) as a subsidiary independent factor were varied in a between-participants design. 60 participants took part in the experiment, completing a number of typical tasks of mobile phone users. The results showed that increased product aesthetics had a positive effect on perceived usability and led to longer task completion times. After a negative usage event had been experimentally induced, usability ratings dropped as expected but user performance on subsequent tasks remained unaffected. An important implication of the study is that the aesthetic properties of a product may have multiple effects that go beyond perceived product attractiveness.     

复杂信息系统界面可用性指标体系研究

随着复杂信息系统在军事领域和民用领域的广泛应用及不断发展,人们对复杂信 息系统显示界面的设计有了更高层面的要求。通过可用性评估指导复杂信息系统界面设计改良, 降低系统复杂性带给用户的工作认知负荷,提高用户绩效成为亟待解决的问题。针对复杂信息 系统界面进行了研究,从界面特征、任务特征、认知特征进行了分析,提出了界面复杂性的影 响因素,构建了复杂度评估指标体系,采用层次分析法针对界面的复杂性的指标权重进行了研 究,并根据构建的复杂度模型提出了相应的可用性指标体系。     

User‐interface design heuristics for developing usable industrial hypermedia applications

Shop floor operators urgently need help to cope with the pressures of the present manufacturing context. One proposed solution is industrial hypermedia applications (IHA). A review of published papers on IHAs has shown that while the potential benefits of such applications, if accepted and used by operators, are well documented, user‐interface design aspects are not. In other words, the rationale used for the user‐interface design is not explained. This article fills the gap by drawing on human–computer interaction and hypermedia literature to present user‐interface design guidelines or heuristics. The latter were incorporated in 2 IHAs developed for this study. Shop floor operators empirically assessed the IHAs through usability trials held in the workplace and provided data on their perceptions of the IHA's ease of use. The findings show that the 7 design heuristics contributed to the usability of the IHAs. However, developers should not apply the design heuristics in isolation but should also elicit user characteristics and task domain. © 2002 Wiley Periodicals, Inc.     

Building Task-Based User Interfaces with ANSI/CEA-2018

The recently approved ANSI/CEA-2018 standard is motivated by the current usability crisis in computer-controlled electronic products. The standard facilitates a new user interface design methodology that uses a task model at runtime to guide users.     

The influence of design aesthetics in usability testing: Effects on user performance and perceived usability

This article examined the effects of product aesthetics on several outcome variables in usability tests. Employing a computer simulation of a mobile phone, 60 adolescents (14-17 yrs) were asked to complete a number of typical tasks of mobile phone users. Two functionally identical mobile phones were manipulated with regard to their visual appearance (highly appealing vs not appealing) to determine the influence of appearance on perceived usability, performance measures and perceived attractiveness. The results showed that participants using the highly appealing phone rated their appliance as being more usable than participants operating the unappealing model. Furthermore, the visual appearance of the phone had a positive effect on performance, leading to reduced task completion times for the attractive model. The study discusses the implications for the use of adolescents in ergonomic research.     

Understanding User Experience with Computer-Based Applications with Different Use Purposes

The concept of user experience emphasizes the importance of understanding users for applications that have various contextual features. To address this issue, this study examines the changes in the relationships among user satisfaction and users' perceptions of usability and aesthetics according to use situations. For data, an experiment was conducted using 15 existing websites with similar levels of usability and aesthetics. Forty-five engineering students participated in the experiment. The results indicated that the relationships among perceived usability, perceived aesthetics, and user satisfaction could be dependent on how users perceived the use purposes and interaction types of the websites. Specifically, the relationship between perceived usability and user satisfaction was stronger for websites requiring users' goal-directed activities, whereas the relationship between perceived aesthetics and user satisfaction was stronger for the websites mainly providing useful information, regardless of the existence of a specific use goal. Also, the strong relationship between perceived usability and perceived aesthetics was more obvious for websites where users mainly wanted to obtain information than for those where users primarily wanted to use the leisure and relaxation content. The findings can be utilized in the design of websites with different contextual features, especially related to use purposes and interaction types.     

Beyond the User Preferences: Aligning the Prototype Design to the Users’ Expectations

It is important for practitioners to conceptualize and tailor a prototype in tune with the users’ expectations in the early stages of the design life cycle so the modifications of the product design in advanced phases are kept to a minimum. According to user preference studies, the aesthetic and the usability of a system play an important role in the user appraisal and selection of a product. However, user preferences are just a part of the equation. The fact that a user prefers one product over the other does not mean that he or she would necessarily buy it. To understand the factors affecting the user's assessment of a product before the actual use of the product and the user's intention to purchase the product we conducted a study, reported in this article. Our study, a modification of a well‐known protocol, considers the users’ preferences of six simulated smartphones each with different combination of attributes. A sample consisting of 365 participants was involved in our analysis. Our results confirm that the main basis for the users’ pre‐use preferences is the aesthetics of the product, whereas our results suggest that the main basis for the user's intention to purchase are the expected usability of the product. Moreover, our analysis reveals that the personal characteristics of the users have different effects on both the users’ preferences and their intention to purchase a product. These results suggest that the designers should carefully balance the aesthetics and usability features of a prototype in tune with the users expectations. If the conceptualization of a product is done properly the redesign cycles after the usability testing can be reduced and speed up the process for releasing the product on the market.     

A blessing,not a curse: Experimental evidence for beneficial effects of visual aesthetics on performance

The present experiment investigated the effect of visual aesthetics on performance. A total of 257 volunteers completed a series of search tasks on a website providing health-related information. Four versions of the website were created by manipulating visual aesthetics (high vs. low) and usability (good vs. poor) in a 2 × 2 between-subjects design. Task completion times and error rates were used as performance measures. A main effect of usability on both error rates and completion time was observed. Additionally, a significant interaction of visual aesthetics and usability revealed that high aesthetics enhanced performance under conditions of poor usability. Thus, in contrast to the notion that visual aesthetics may worsen performance, visual aesthetics even compensated for poor usability by speeding up task completion. The practical and theoretical implications of this finding are discussed.     

Recommender Systems: An Introduction,by Dietmar Jannach,Markus Zanker,Alexander Felfernig,and Gerhard Friedrich

In addressing user experience issues, users’ perceptions and emotions need to be considered important. This study examines the relationships between perceived usability/aesthetics and emotional valence/arousal/engagement through an experiment using 15 existing websites from various domains and questionnaire items developed to measure users’ responses. According to the experimental results, both perceived usability and perceived aesthetics were positively correlated with emotional valence and negatively correlated with emotional engagement. No specific relationship was found between perceived usability/aesthetics and emotional arousal. Perceived aesthetics potentially had a greater impact on valence than perceived usability. Unlike valence, engagement could be more influenced by perceived usability than by perceived aesthetics. These findings can be utilized as bases for applying users’ emotional responses in each dimension to the product-use situations in the chain of perceptions, emotions, and behaviors.     

The influence of product aesthetics and usability over the course of time: a longitudinal field experiment

A longitudinal field experiment was carried out over a period of 2 weeks to examine the influence of product aesthetics and inherent product usability. A 2 × 2 × 3 mixed design was used in the study, with product aesthetics (high/low) and usability (high/low) being manipulated as between-subjects variables and exposure time as a repeated-measures variable (three levels). A sample of 60 mobile phone users was tested during a multiple-session usability test. A range of outcome variables was measured, including performance, perceived usability, perceived aesthetics and emotion. A major finding was that the positive effect of an aesthetically appealing product on perceived usability, reported in many previous studies, began to wane with increasing exposure time. The data provided similar evidence for emotion, which also showed changes as a function of exposure time. The study has methodological implications for the future design of usability tests, notably suggesting the need for longitudinal approaches in usability research. PRACTITIONER SUMMARY: This study indicates that product aesthetics influences perceived usability considerably in one-off usability tests but this influence wanes over time. When completing a usability test it is therefore advisable to adopt a longitudinal multiple-session approach to reduce the possibly undesirable influence of aesthetics on usability ratings.     

Product interface design: A participatory approach based on virtual reality

The usability of the user interface is a key aspect for the success of several industrial products. This assumption has led to the introduction of numerous design methodologies addressed to evaluate the user-friendliness of industrial products. Most of these methodologies follow the participatory design approach to involve the user in the design process. Virtual Reality is a valid tool to support Participatory Design, because it facilitates the collaboration among designers and users.The present study aims to evaluate the feasibility and the efficacy of an innovative Participatory Design approach where Virtual Reality plays a ‘double role’: a tool to evaluate the usability of the virtual product interface, and a communication channel that allows users to be directly involved in the design process as co-designers.In order to achieve these goals, we conducted three experiments: the purpose of the first experiment is to determine the influence of the virtual interface on the usability evaluation by comparing “user–real product” interaction and “user–virtual product” interaction. Subsequently, we tested the effectiveness of our approach with two experiments involving users (directly or through their participation in a focus group) in the redesign of a product user interface. The experiments were conducted with two typologies of consumer appliances: a microwave oven and a washing machine.     

Visual inspection with augmented reality head-mounted display: An Australian usability case study

Augmented reality (AR) is an Industry 4.0 technology. For more than a decade, advancements in AR technology and their applications have been expected to revolutionise the manufacturing industry and deliver quality and productivity gains. However, due to factors such as equipment costs, skills shortages and technological limitations of AR devices, operational deployment beyond prototypes has been constrained. Real-world, usability studies can explore barriers to implementation and improve system design. This paper details a mixed method usability case study of an AR head-mounted display (HMD) to perform a short, simple visual inspection task. Twenty-two participants from South Australian manufacturing businesses inspected a pump and pipe skid while working at height. Overall, workload demands for the task were considered acceptable and just below the “low” workload threshold (NASA Task Load Index, mean = 29.3) and the system usability was rated “average” (system usability scale, mean = 68.5). The results suggest the task did not place too high a burden on users and was an appropriate initial exposure to AR HMDs, but further refinement to the interface would be desirable before implementation to minimise frustration and promote learning. Users were enthusiastic and open-minded about the AR HMD although results indicate that even with recent advancements in AR HMD technology, interactions between the task, technology and environment continue to cause human and technical challenges—some of which are relatively straightforward to address but others are dependent on larger-scale efforts.     

Interface-Walkthroughs: efficient collaborative testing

A walkthrough facility for testing the usability of a user interface design before the software is written or a prototype is built is described. The use of this method to evaluate screen panels, which may include pull-down menus, dialogue boxes, palettes, and other interface elements, is reported. These pluralistic usability walkthroughs have four characteristics. First, three types of people participate in the walkthrough: representatives of the expected user population, product developers, and human factors professionals. Second, the user interface panels are presented in the same order they would be confronted online. Third, participants write down their responses on each panel before there is any discussion. Finally, the representative users speak first when discussing the panels and the experts speak only when the users have exhausted their comments. The limitations and benefits of the walkthrough approach are examined