Too good to be bad: Favorable product expectations boost subjective usability ratings

In an experiment conducted to study the effects of product expectations on subjective usability ratings, participants (N = 36) read a positive or a negative product review for a novel mobile device before a usability test, while the control group read nothing. In the test, half of the users performed easy tasks, and the other half hard ones, with the device. A standard usability test procedure was utilized in which objective task performance measurements as well as subjective post-task and post-experiment usability questionnaires were deployed. The study revealed a surprisingly strong effect of positive expectations on subjective post-experiment ratings: the participants who had read the positive review gave the device significantly better post-experiment ratings than did the negative-prime and no-prime groups. This boosting effect of the positive prime held even in the hard task condition where the users failed in most of the tasks. This finding highlights the importance of understanding: (1) what kinds of product expectations participants bring with them to the test, (2) how well these expectations represent those of the intended user population, and (3) how the test situation itself influences and may bias these expectations.     

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 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.     

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.     

Product design and apparent usability. The influence of novelty in product appearance

This research enhances our understanding of the relationship between aesthetics and usability by investigating the effects of novelty in product appearance on the apparent usability of a product. In two experimental studies using washing machines and digital cameras as stimuli, we systematically manipulated the level of novelty (low vs. high) in the product appearance by changing the product's color or shape. Participants were presented with one of these product appearances and a list of the product's technical specifications. Next, participants indicated how difficult or easy they expected the usage of the product to be. Our findings demonstrate that because people associate a high level of novelty with technological advancement, novelty in a product appearance negatively affects their expectations of a product's usability at the point of sale. Furthermore, novices are more likely to use the level of novelty as a cue for a product's apparent usability than experts.     

Expressive and classical aesthetics: two distinct concepts with highly similar effect patterns in user–artefact interaction

This study examined the utility of the concept of expressive aesthetics by testing websites that did or did not match this concept. A website scoring highly on this concept was created and was then compared to websites that were either non-aesthetic or corresponded to the concept of classical aesthetics. Sixty website users of a broad age range (18–60 years) were allocated to three experimental groups (expressive, classical, and non-aesthetic) and asked to complete a series of information search tasks. During the experiment, measures were taken of performance, perceived usability, perceived aesthetics, emotion, and trustworthiness. The results showed that expressive aesthetics can be considered a distinct concept. It also emerged that the website scoring high on expressive aesthetics shows a similar pattern of results to classical aesthetics. Both aesthetically appealing websites received higher ratings of perceived usability and trustworthiness than the non-aesthetic website. The effects of website aesthetics on subjective measures were not moderated by age.     

The importance of usability in product choice: A mobile phone case study

Usability has become established as an important aspect of product design. This paper describes an investigation that was carried out to identify the importance of usability in product choice related to other product attributes. Interviews were initially carried out to identify possible attributes that contribute to product choice. Experiments were then undertaken using the methods of active information search, structured preference elicitation, ranking and interviews in order to find out what attributes were important to people when choosing an example product – mobile phones. It was found that usability is indeed important in product choice but perhaps not as much as users themselves believe. Other attributes that were found to be more important were features, aesthetics and cost. The process of product choice was found to be complex and it may be the case that people have come to expect usability in their products. Further research is needed to understand more fully the changing role of usability in product choice and to further improve the quality of the user–product relationship.     

The role of non-visual aesthetics in consumer product evaluation

The present article addresses the impact of non-visual aesthetics of consumer products on the outcomes of usability tests such as perceived usability, user performance and user affect. Building on the research surrounding the impact of visual aesthetics in usability testing, the present work aimed to determine whether the same pattern of effects repeatedly found for visual aesthetics will also be found for non-visual aesthetics. A series of three experiments was carried out, all examining sound and touch as two prominent dimensions of non-visual aesthetics. To increase the robustness of the results, the experiments were conducted with three different consumer products, which were a smartphone (N=60), vacuum cleaner (N=60), and video racing game (N=60). Although manipulation checks confirmed that users generally experienced both sound and tactile product properties as intended by the experimental manipulation, in none of the studies the results showed an effect on perceived usability. Other outcome variables such as affect and performance showed a few selected effects. Overall, this suggests that findings from the field of visual aesthetics cannot be easily transferred to the domain of non-visual aesthetics. The findings of the present studies are discussed within the framework of Schifferstein’s work on sensory dominance.     

Is beautiful really usable? Toward understanding the relation between usability,aesthetics, and affect in HCI

This paper analyzes the relation between usability and aesthetics. In a laboratory study, 80 participants used one of four different versions of the same online shop, differing in interface-aesthetics (low vs. high) and interface-usability (low vs. high). Participants had to find specific items and rate the shop before and after usage on perceived aesthetics and perceived usability, which were assessed using four validated instruments. Results show that aesthetics does not affect perceived usability. In contrast, usability has an effect on post-use perceived aesthetics. Our findings show that the “what is beautiful is usable” notion, which assumes that aesthetics enhances the perception of usability can be reversed under certain conditions (here: strong usability manipulation combined with a medium to large aesthetics manipulation). Furthermore, our results indicate that the user’s affective experience with the usability of the shop might serve as a mediator variable within the aesthetics–usability relation: The frustration of poor usability lowers ratings on perceived aesthetics. The significance of the results is discussed in context of the existing research on the relation between aesthetics and usability.     

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.     

The influence of user expertise and prototype fidelity in usability tests

An empirical study examined the impact of user expertise and prototype fidelity on the outcomes of a usability test. User expertise (expert vs. novice) and prototype fidelity (paper prototype, 3D mock-up, and fully operational appliance) were manipulated as independent variables in a 2 × 3 between-subjects design. Employing a floor scrubber as a model product, 48 users carried out several cleaning tasks. Usability problems identified by participants were recorded. Furthermore, performance, system management strategies and perceived usability were measured. The results showed that experts reported more usability problems than novices but these were considered to be less severe than those reported by novices. Reduced fidelity prototypes were generally suitable to predict product usability of the real appliance. The implications for the running of usability tests are specific to the fidelity of the prototype.     

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.     

The Impact of Cognitive Style on User Preference Based on Usability and Aesthetics for Computer-Based Systems

Understanding target users is a crucial issue in establishing design and marketing strategies for computer-based applications. To contribute to the comprehension of target users, this study examines the effect of cognitive style (imagers vs. verbalizers) on user preference based on perceived usability and perceived aesthetics through an experiment using four simulated systems with different levels of usability and aesthetics. Forty-two imagers and 31 verbalizers participated in the experiment. The results of the analyses of variance indicated that, before actual use, the effect of the aesthetics factor on user preference was significantly different between imagers and verbalizers but that of the usability factor was not. The difference between imagers and verbalizers with respect to the effect of the aesthetics/usability factor on time performance was not sufficiently demonstrated, nor was the difference between the two cognitive styles with regard to the effect of the aesthetics/usability factor on user preference after actual use. For the combined experimental data of users' responses before and after actual use, the interaction effect between cognitive styles and actual use on user preference was not significant. Some possible reasons for these results and the possibilities of an important role of cognitive style in users' preference making are discussed here. Further studies are necessary to better examine the impact of cognitive style.     

Perceptions of electronic navigation displays

This study evaluated aesthetics and usability of in-vehicle electronic navigation maps. Experiment 1 examined map displays that varied in the amount of information presented, abstraction level, graphic/colour style and the existence of landmarks in both urban and rural environments using objective and subjective measures. Twenty participants performed navigation/localisation tasks using various map configurations while driving a driving simulator and completed usability and aesthetic questionnaires. The minimal detail map produced better performances and higher usability and aesthetic ratings when using maps with no landmarks. Adding information in the form of landmarks was found advantageous compared to additional textual information. Abstractions were most advantageous when combined with minimal amount of detail. Moderate abstractions were sufficient for obtaining the desired benefits when more details were present. The graphic/colour style affected subjective perceptions. Overall, high correlations were found for the perceived aesthetics and usability scales, however, low correlations were found between actual usability (i.e. performance) and perceived usability pointing to the importance of using both objective and subjective usability measures. Experiment 2 examined how maps varying in their aesthetic level (aesthetic versus non-aesthetic), different colour arrangements, and 2D versus 3D landmarks affect subjective and objective measures. Participants distinguished between usability and aesthetic perceptions and usability perceptions were less affected by aesthetics when the aesthetic level of the maps was low. Colour arrangement did not affect the measures examined. Both 2D and 3D landmarks were found to be aesthetic and usable. We conclude this article with guidelines for designing in-vehicle navigation map displays.     

A study of usability principles and interface design for mobile e-books

This study examined usability principles and interface designs in order to understand the relationship between the intentions of mobile e-book interface designs and users' perceptions. First, this study summarised 4 usability principles and 16 interface attributes, in order to conduct usability testing and questionnaire survey by referring to Nielsen (1993), Norman (2002), and Yeh (2010), who proposed the usability principles. Second, this study used the interviews to explore the perceptions and behaviours of user operations through senior users of multi-touch prototype devices. The results of this study are as follows: (1) users' behaviour of operating an interactive interface is related to user prior experience; (2) users' rating of the visibility principle is related to users' subjective perception but not related to user prior experience; however, users' ratings of the ease, efficiency, and enjoyment principles are related to user prior experience; (3) the interview survey reveals that the key attributes affecting users' behaviour of operating an interface include aesthetics, achievement, and friendliness.     

基于观点挖掘的产品可用性建模与评价

提出基于观点挖掘的产品可用性建模与评价方法。以Web上的产品评论为数据,利用观点挖掘的方法从非结构化评论中抽取结构化数据,选取与可用性相关的产品特征,使用因子分析法提取影响产品可用性的公共因子,建立产品可用性模型。对产品可用性进行评价,结果表明,该方法可以有效地从用户角度发掘产品可用性中存在的缺陷,为产品设计提供依据。     

The influence of prototype fidelity and aesthetics of design in usability tests: effects on user behaviour, subjective evaluation and emotion

An empirical study examined the impact of prototype fidelity on user behaviour, subjective user evaluation and emotion. The independent factors of prototype fidelity (paper prototype, computer prototype, fully operational appliance) and aesthetics of design (high vs. moderate) were varied in a between-subjects design. The 60 participants of the experiment were asked to complete two typical tasks of mobile phone usage: sending a text message and suppressing a phone number. Both performance data and a number of subjective measures were recorded. The results suggested that task completion time may be overestimated when a computer prototype is being used. Furthermore, users appeared to compensate for deficiencies in aesthetic design by overrating the aesthetic qualities of reduced fidelity prototypes. Finally, user emotions were more positively affected by the operation of the more attractive mobile phone than by the less appealing one.     

Product design enhancement using apparent usability and affective quality

In this study, apparent usability and affective quality were integrated in a design framework called the Usability Perception and Emotion Enhancement Model (UPEEM). The UPEEM was validated using structural equation modeling (SEM). The methodology consists of four phases namely product selection, attribute identification, design alternative generation, and design alternative evaluation. The first stage involved the selection of a product that highly involves the consumer. In the attribute identification stage, design elements of the product were identified. The possible values of these elements were also determined for use in the experimentation process. Design of experiments was used to identify how the attributes will be varied in the design alternative stage and which of the attributes significantly contribute to affective quality, apparent usability, and desirability in the design evaluation stage. Results suggest that product attributes related to form are relevant in eliciting intense affect and perception of usability in mobile phones especially those directly related to functionality and aesthetics. This study considered only four product attributes among so many due to the constraints of the research design employed. Attributes related to aesthetic perception of a product enhance apparent usability such as those related to dimensional ratios.     

The influence of laboratory set-up in usability tests: effects on user performance,subjective ratings and physiological measures

This article examines the influences of situational factors on user behaviour in usability tests. Sixty participants carried out two tasks on a computer-simulated prototype of a mobile phone. Employing a 3 × 2 mixed experimental design, laboratory set-up was varied as a between-subjects variable (presence of facilitator and two non-interactive observers, presence of facilitator or no person present) while task difficulty was manipulated as a within-subjects variable (low vs. high). Performance data, subjective measures and physiological parameters (e.g. heart rate variability) were taken. The results showed that the presence of non-interactive observers during a usability test led to a physiological stress response, decreased performance on some measures and affected the emotional state of test participants. The presence of a facilitator (i.e. a participating observer) also influenced the emotional state of the test participant. Practitioners involved in usability testing need to be aware of undue influences of observers, in particular, if the observers are non-interactive. The findings presented in this paper have implications for the practice of usability testing. They indicated a considerable influence of observers on test participants (physiology and emotions) and on the outcomes of usability tests (performance measures). This should be considered when selecting the set-up of a usability testing procedure.     

Effects of accessible website design on nondisabled users: age and device as moderating factors

This study examined how implementing recommendations from Web accessibility guidelines affects nondisabled people in different age groups using different technical devices. While recent research showed positive effects of implementing such recommendations for nondisabled users, it remains unclear whether such effects would apply to different age groups and kind of devices. A 2 × 2 × 2 design was employed with website accessibility (high accessibility vs. very low accessibility), age (younger adults vs. older adults) and type of device (laptop vs. tablet) as independent variables. 110 nondisabled participants took part in a usability test, in which performance and satisfaction were measured as dependent variables. The results showed that higher accessibility increased task completion rate, task completion time and satisfaction ratings of nondisabled users. While user age did not have any effects, users showed faster task completion time under high accessibility when using a tablet rather than a laptop. The findings confirmed previous findings, which showed benefits of accessible websites for nondisabled users. These beneficial effects may now be generalised to a wide age range and across different devices.

Practitioner Summary: This work is relevant to the design of websites since it emphasises the need to consider the characteristics of different user groups. Accessible website design (aimed at users with disabilities) leads to benefits for nondisabled users across different ages. These findings provide further encouragement for practitioners to apply WCAG 2.0.