Problem solving,confidence and frustration when carrying out familiar tasks on non-familiar mobile devices

Smart mobile devices, which are hand-held electronic devices with an advanced operating system (such as the Android platform) connected via a wireless protocol, have become an integral and essential part of our everyday life, and support both social and workplace activities. However, adopting mobile technology within the workplace setting can give rise to challenges that impact user behaviour and performance. A study was carried out amongst 90 participants located in two countries, using internet connectivity as a case study. Confidence and frustration have previously been connected with technology competence, but this was not applied to a workplace scenario during problem-solving, when users are assigned an unfamiliar smart mobile device. This research focuses on identifying the link between workplace users' levels of confidence and frustration when seeking to independently solve problems whilst completing familiar tasks on new smart mobile devices. A detailed video analysis of users' attitudes and behaviour during problem-solving was conducted, emphasising a correlation between attitudes and behaviour towards completing a task.     

Highlighting items as means of adaptive assistance

Providing adaptive help during interaction with the system can be used to assist users in accomplishing their tasks. We propose providing guidance by highlighting the steps required for performing a task that the user intends to complete according to the prediction of a system. We present a study aimed at examining whether highlighting intended user steps in menus and toolbars as a means of assisting users in performing tasks is useful in terms of user response and performance. We also examined the effects of different accuracy levels of help and the control format on user response and performance. An experiment was conducted in which 64 participants performed tasks using menus and toolbars of a simulated email application. Participants were offered a highlighted guidance of the required steps in varying levels of accuracy (100%, 80%, 60% and no guidance). Our results support the benefits of highlighted help both in user performance times and in user satisfaction from receiving such assistance. Users found the assistance necessary and helpful and by the same token not unduly intrusive. Additionally, users felt that such assistance generally helped in reducing performance time on tasks. We did not find a significant difference when users receiving help at 80% accuracy was compared to those receiving help at 100% accuracy; however, such a difference does appear for those receiving 60% accuracy. In such cases, we found that the user's satisfaction level, perceived usefulness and trust in the system decreased while their notion of perceived intrusiveness increased. We conclude that assisting users by highlighting the required steps is useful so long as the minimal accuracy level of help is higher than 60%. Our study has implications on the implementation of highlighting next steps as a means of adaptive help and on integrating probability-based algorithms such as intention prediction to adaptive assistance systems.     

What does it mean to be good at using a mobile device? An investigation of three levels of experience and skill

An increasing number of computer users lack formal training in operating their devices. These daily users cannot be described as novices or experts within the predominant view of expertise. In order to describe and better understand this type of self-taught intermediate level of skill, 10 casual users of a high-end smartphone series were compared to 10 novices and 4 professionals (help desk personnel) in their learning histories, task performance, and cognitive outcomes. Our study suggests that this type of self-taught intermediate level of skill is device-specific. Experienced users (casual users and experts) exhibited superior performance for representative tasks. This is mainly attributable to faster navigation and better knowledge of interface terminology, not to deeper conceptual representation of the problems. Interviews suggest that this skill is the consequence of routine use and three recurring learning events: familiarization, following of media, and ad hoc problem-solving situations. We conclude by discussing why intermediate levels of skill deserve more attention in HCI research.     

Designing for user attention: A method for supporting unobtrusive routine tasks

The automation of user routine tasks is one of the most important challenges in the development of Ambient Intelligence systems. However, this automation may be annoying since some tasks may grab users attention in inappropriate situations. Since user attention is a valuable resource, task automation must behave in a considerate manner demanding user attention only when it is required. To address this issue, this work presents a systematic method for supporting the design and automation of unobtrusive routine tasks that can adjust their obtrusiveness level at runtime according to the user attentional resources and context. This method proposes to design the routine tasks that the system must carry out and how they must interact with users in terms of obtrusiveness. The method also provides a software infrastructure that makes the execution of the tasks at the appropriate obtrusiveness degree a reality. Finally, the system has been validated by means of usefulness and performance tests and a practical case study that demonstrates the correctness and applicability of our approach without compromising system performance.     

LIY: learn-it-yourself software interfaces

An increasing number of people are becoming users of unfamiliar software. They can be genuinely "new" computer users or part of a growing group who are transferring skills and knowledge from a familiar product such as a word processor to a functionally similar, but different, unfamiliar one. The problem for users in this position is that they do not have access to training courses to teach them how to use such software and are usually forced to rely on text-based documentation. LIY is a method for producing computer-based tutorials to teach the user ofasoftware product.This paper describes how LIY is, in turn, (1) a method for application system design which recognizes the need for tutorial design (a task analysis and user interface specification provide information structures that are passed to the tutorial designer); (2) a support environment for the tutorial designer (in addition to prompting for courseware for nodes in the task analysis, LIY provides a ready-made rule base for constraining the degree of learner control available while the tutorial is in use. The designer is able to tailor this rule base for a specific tutorial); and (3) a tutorial delivery environment (the tutorial adapts to individual learners and offers a degree of learner control).     

Practice and carryover effects when using small interaction devices

The use of interaction devices in modern work often challenges the human motor system, especially when these devices introduce unfamiliar transformations to the user. In this paper we evaluated expert performance and skill differences between experts and novices when using small motion- and force-controlled interaction devices (touchpad and mini-joystick) in an applied text-editing task. Firstly, experts performed better with their familiar input device than with an unfamiliar one. Particularly touchpad experts operating the unfamiliar mini-joystick showed highly asymmetric carryover costs. Results showed that the efficient performance of experts depended on domain-specific skills, which were not transferable. Secondly, with considerable practice (more than observed for simple and short tasks) novices were brought up to higher levels of performance. The motion-transformation between hand and cursor action was easier in understanding and application than the force-transformation. Thus, the touchpad was used more efficiently than the mini-joystick. In conclusion, practice effects found so far are considerably underestimated when it comes to an applied task. The results give reason to develop and implement skill-sensitive training procedures, since the acquisition of domain-specific skills is critical for expert performance. As a consequence, training procedures might be essential for complex applications and/or unfamiliar device transformations.     

Rehabilitation program integrating virtual environment to improve orientation and mobility skills for people who are blind

This paper presents the integration of a virtual environment (BlindAid) in an orientation and mobility rehabilitation program as a training aid for people who are blind. BlindAid allows the users to interact with different virtual structures and objects through auditory and haptic feedback. This research explores if and how use of the BlindAid in conjunction with a rehabilitation program can help people who are blind train themselves in familiar and unfamiliar spaces. The study, focused on nine participants who were congenitally, adventitiously, and newly blind, during their orientation and mobility rehabilitation program at the Carroll Center for the Blind (Newton, Massachusetts, USA). The research was implemented using virtual environment (VE) exploration tasks and orientation tasks in virtual environments and real spaces. The methodology encompassed both qualitative and quantitative methods, including interviews, a questionnaire, videotape recording, and user computer logs. The results demonstrated that the BlindAid training gave participants additional time to explore the virtual environment systematically. Secondly, it helped elucidate several issues concerning the potential strengths of the BlindAid system as a training aid for orientation and mobility for both adults and teenagers who are congenitally, adventitiously, and newly blind.     

Measuring Cognitive Load Using Linguistic Features: Implications for Usability Evaluation and Adaptive Interaction Design

An intelligent adaptable system, aware of a user’s experienced cognitive load, may help improve performance in complex, time-critical situations by dynamically deploying more appropriate output strategies to reduce cognitive load. However, measuring a user’s cognitive load robustly, in real-time is not a trivial task. Many research studies have attempted to assess users’ cognitive load using different measurements, but these are often unsuitable for deployment in real-life applications due to high intrusiveness. Relatively novel linguistic behavioral features as potential indices of user’s cognitive load is proposed. These features may be collected implicitly and nonintrusively supporting real-time assessment of users’ cognitive load and accordingly allowing adaptive usability evaluation and interaction. Results from a laboratory experiment show significantly different linguistic patterns under different task complexities and cognitive load levels. Implications of the research for adaptive interaction are also discussed, that is, how the cognitive load measurement-based approach could be used for user interface evaluation and interaction design improvement.     

异构计算系统中弹性节能调度策略研究

目前,节能已成为异构计算系统中减少电量开销、提高系统可靠性和保护环境的重要研究内容.传统的节能调度策略侧重于研究如何节能而忽略了用户对任务完成时间的期望,使得任务执行效果受到较大影响.特别是当系统负载较重时,由于电压调节缺乏自适应性,导致在某些情况下(如应急服务)的任务执行效果不可容忍.文中提出一种弹性节能调度策略(Elastic Energy-Aware Scheduling,EEAS),用于动态调度异构计算系统中非周期、独立任务.EEAS策略根据系统负载情况在系统节能与用户期望之间进行权衡,即当系统负载较重时,EEAS优先考虑用户期望,通过动态调整计算节点局部队列中等待任务的执行电压提高任务完成率;当系统负载较轻时,EEAS在尽量满足用户期望的基础上最大限度地降低任务执行电压以实现节能.文中通过大量的模拟实验比较了EEAS、GEA、HVEA和LVEA的性能.实验结果表明,EEAS的调度质量优于其他策略,可有效提高系统弹性.     

Understanding novelty: how task structure and tool familiarity moderate performance

Consumers and corporate end users are regularly faced with the challenge of adapting to new technology tools and their user interfaces. Understanding the role of user experience in using these new interfaces is an important aspect of assessing and planning for how new innovations are received. Through a controlled laboratory experiment in the information retrieval domain, we find that the effect of task (web search) familiarity on performance depends on the task structure (open-ended versus closed-ended) and the degree of tool familiarity (a traditional textual list versus a novel graphical interface for presenting web search results). Our results show that task experience has a positive effect on performance when the task structure is closed-ended and the interface is familiar, and a negative effect when the task structure is open-ended and the interface is unfamiliar. This study not only adds to the literature on user experience in the context of IT use, but also has practical implications for the testing and adoption of new technologies, indicating that novices may be better, or at least an important group, for testing truly novel tools and their interfaces.     

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.     

The effect of testing location on usability testing performance, participant stress levels, and subjective testing experience

The effect of testing location on usability test elements such as stress levels and user experience is not clear. A comparison between traditional lab testing and synchronous remote testing was conducted. The present study investigated two groups of users in remote and traditional settings. Within each group participants completed two tasks, a simple task and a complex task. The dependent measures were task time taken, number of critical incidents reported, and user-reported anxiety score. Task times differed significantly between the physical location condition; this difference was not meaningful for real world application, and likely introduced by overhead regarding synchronous remote testing methods. Critical incident reporting counts did not differ in any condition. No significant differences were found in user reported stress levels. Subjective assessments of the study and interface also did not differ significantly. Study findings suggest a similar user testing experience exists for remote and traditional laboratory usability testing.     

Analyses of user rationality and system learnability: performing task variants in user tests

No systematic empirical study on investigating the effects of performing task variants on user cognitive strategy and behaviour in usability tests and on learnability of the system being tested has been documented in the literature. The current use-inspired basic research work aims to identify the underlying cognitive mechanisms and the practical implications of this specific endeavour. The focus of our work was to assess user rationality and system learnability. The software application tested was a multilingual learning resource repository. Eleven German and eleven Slovenian participants were involved in two user tests (UTs). Usability problems (UPs) identified in two quasi-isomorphic tasks were categorized with respect to a scheme of associated skills. Actions of the two tasks of each of the 22 users were segmented and coded according to a scheme of cognitive activities. Results showed that generally the users adopted different strategies for working out the given task and its variant, and that the system could be proved learnable. User Rational Action Model and implications for future research on user tests are inferred.     

A feedback control approach to maintain consumer information load in online shopping environments

The heterogeneity of e-commerce users requires online shopping environments to advance from a simple framework to one that is adaptive. This need results from the negative consequences of user frustration due to information load. We used a feedback control theory based approach to address the online consumer information overload issue in an adaptive manner. To demonstrate the efficacy of this feedback control approach, a design science method evaluated the feedback controller. The main effect was that the dynamic adaptivity did not have to rely on summarizing data for inference to the individual. The proposed feedback control design is therefore a robust and viable option for organizations to incorporate into their online shopping environments to accommodate user variation of information load for e-commerce adaptivity.     

The MSIIA Experiment: Using Speech to Enhance Human Performance on a Cognitive Task

We performed an exploratory study to examine the effects of speech-enabled input on a cognitive task involving analysis and annotation of objects in aerial reconnaissance videos. We added speech to an information fusion system to allow for hands-free annotation in order to examine the effect on efficiency, quality, task success, and user satisfaction. We hypothesized that speech recognition could be a cognitive-enabling technology by reducing the mental load of instrument manipulation and freeing up resources for the task at hand.Despite the lack of confidence participants had for the accuracy and temporal precision of the speech-enabled input, each reported that speech made it easier and faster to annotate images. When speech input was available, participants chose speech over manual input to make all annotations. Several participants noted that the additional modality was very effective in reducing the necessity to navigate controls and in allowing them to focus more on the task. Quantitative results suggest that people could potentially identify images faster with speech. However, people did not annotate better with speech (precision was lower, and recall was significantly lower). We attribute the lower recall/precision scores to the lack of undo and editing capabilities and insufficient experience by naïve users in an unfamiliar domain.This formative study has provided feedback for further development of the system augmented with speech-enabled input, as our results show that the availability of speech may lead to improved performance of expert domain users on more complicated tasks.     

Analyses of user rationality and system learnability: performing task variants in user tests

No systematic empirical study on investigating the effects of performing task variants on user cognitive strategy and behaviour in usability tests and on learnability of the system being tested has been documented in the literature. The current use-inspired basic research work aims to identify the underlying cognitive mechanisms and the practical implications of this specific endeavour. The focus of our work was to assess user rationality and system learnability. The software application tested was a multilingual learning resource repository. Eleven German and eleven Slovenian participants were involved in two user tests (UTs). Usability problems (UPs) identified in two quasi-isomorphic tasks were categorized with respect to a scheme of associated skills. Actions of the two tasks of each of the 22 users were segmented and coded according to a scheme of cognitive activities. Results showed that generally the users adopted different strategies for working out the given task and its variant, and that the system could be proved learnable. User Rational Action Model and implications for future research on user tests are inferred.     

A glass box approach to adaptive hypermedia

Utilising adaptive interface techniques in the design of systems introduces certain risks. An adaptive interface is not static, but will actively adapt to the perceived needs of the user. Unless carefully designed, these changes may lead to an unpredictable, obscure and uncontrollable interface. Therefore the design of adaptive interfaces must ensure that users can inspect the adaptivity mechanisms, and control their results. One way to do this is to rely on the user's understanding of the application and the domain, and relate the adaptivity mechanisms to domain-specific concepts. We present an example of an adaptive hypertext help system POP, which is being built according to these principles, and discuss the design considerations and empirical findings that lead to this design.     

Complementary menus: Combining adaptable and adaptive approaches for menu interface

This study proposes a method of coupling adaptable and adaptive approaches to the design of menus. The proposed complementary menu types incorporate both adaptability and adaptivity by dividing and allocating menu adaptation roles to the user and the system. Four different types of interface adaptation (i.e., adaptable with/without system support and adaptive with/without user control) were defined. They were implemented in a hypothetical prototype mobile phone via a hotlist (an additional collection of quickly accessible items). A controlled lab experiment was conducted to compare the menu types and investigate the effects of the system support in the adaptable menus and the user control in the adaptive menus. Twenty subjects participated in the experiment and performed menu selection tasks. Both performance and user satisfaction measures were collected. The results showed that adaptable and adaptive menus were superior to the traditional one in terms of both performance and user satisfaction. Providing system support to the adaptable menu not only increased the users’ perception of the efficiency of selection, but also reduced the menu adaptation time. Important implications for the design of menus are described and valuable insights into the menu interface adaptation were gained from the quantitative and qualitative analyses of the experimental results.

Relevance to industry

The evaluation experiment conducted in this study may provide valuable information to designers of adaptive or adaptable menus. Adding system support to adaptable menu would be an attractive option to consider. Also, the results of a user survey provide useful information to the practitioners in mobile phone industry on the features users accessed most frequently.     

Are Two Better Than One? A Comparison Between Single- and Dual-Monitor Work Stations in Productivity and User’s Windows Management Style

Multiple monitors are commonly used in the workplace nowadays. This study compares user productivity and windows management style (WMS) on single- and dual-monitor work stations for engineering tasks of three complexity levels. Four productivity measures including task time, cursor movement, the number of window switches, and the number of mouse clicks were compared. The results showed that dual-monitor setting resulted in significantly less window switches and mouse clicks. Most users preferred dual-monitor setting. To understand how users manage multiple windows in completing their tasks, a new WMS categorization method is proposed, toggler and resizer, and user behavior was categorized into one of these two styles. More users adopted “toggler” style, but as the task complexity level increased, some “toggler” style users switched to “resizer” style.     

Investigating users’ intuitive interaction with complex artefacts

This paper examines the role of intuition in the way that people operate unfamiliar devices. Intuition is a type of cognitive processing that is often non-conscious and utilises stored experiential knowledge. Intuitive interaction involves the use of knowledge gained from other products and/or experiences. Two initial experimental studies revealed that prior exposure to products employing similar features helped participants to complete set tasks more quickly and intuitively, and that familiar features were intuitively used more often than unfamiliar ones. A third experiment confirmed that performance is affected by a person's level of familiarity with similar technologies, and also revealed that appearance (shape, size and labelling of features) seems to be the variable that most affects time spent on a task and intuitive uses during that time. Age also seems to have an effect. These results and their implications are discussed.