Stephen Kimani

Appropriating and assessing heuristics for mobile computing

Mobile computing presents formidable challenges not only to the design of applications but also to each and every phase of the systems lifecycle. In particular, the HCI community is still struggling with the challenges that mobile computing poses to evaluation. Expert-based evaluation techniques are well known and they do enable a relatively quick and easy evaluation. Heuristic evaluation, in particular, has been widely applied and investigated, most likely due to its efficiency in detecting most of usability flaws at front of a rather limited investment of time and human resources in the evaluation. However, the capacity of expert-based techniques to capture contextual factors in mobile computing is a major concern. In this paper, we report an effort for realizing usability heuristics appropriate for mobile computing. The effort intends to capture contextual requirements while still drawing from the inexpensive and flexible nature of heuristic-based techniques. This work has been carried out in the context of a research project task geared toward developing a heuristic-based evaluation methodology for mobile computing. This paper describes the methodology that we adopted toward realizing mobile heuristics. It also reports a study that we carried out in order to assess the relevance of the realized mobile heuristics by comparing their performance with that of the standard/traditional usability heuristics. The study yielded positive results in terms of the number of usability flaws identified and the severity ranking assigned.

VidaMine: a visual data mining environment

Abstract That the already vast and ever-increasing amounts of data still do present formidable challenges to effective and efficient acquisition of knowledge is by no means an exaggeration. The knowledge discovery process entails more than just the application of data mining strategies. There are many other aspects including, but not limited to: planning, data pre-processing, data integration, evaluation and presentation. The human-vision channel is capable of recognizing and understanding data at an instant. Effective visual strategies can be used to tap the outstanding human visual channel in extracting useful information from data. Unlike is the case with most research efforts, the exploitation should be employed not just at the beginning or at the end of the knowledge discovery process but across the entire discovery process. In essence, this calls for the development of an effective user/visual component, the development of an overall framework that can support the entire discovery process/all discovery phases, and the strategic placement of the visual component in that framework. Key issues of this component will be the open architecture, allowing extensions and adaptations to specific mining environments, and the precise semantics and syntax, allowing an optimal integration between the presentation and the computation.

A no-frills approach for accessible Web-based learning material

Most of the efforts for supporting the preparation and deployment of accessible Web-based learning material propose guidelines that prevalently address technical accessibility issues. However, little or no consideration is given to the didactical experts, and thus their didactical experience, in the learning material development. Moreover, the aforementioned guidelines tend to provide high-level/generic indications on alternative forms of didactical content for equivalent access of the content. Nonetheless, the sole provision of equivalent forms does not guarantee the retention of desirable user interface aspects such as effectiveness and efficiency. While we do acknowledge the role of such guidelines, we do propose that the didactical experts be provided with a non-technical recourse that can enable them to contribute to the development process of accessible Web-based learning content. In particular, this work proposes tapping into the experience of the didactical experts by providing them with an avenue through which they can appropriately choose relevant and alternative didactical content toward developing and deploying accessible Web-based learning material.

A proposal toward the development of accessible e-learning content by human involvement

Most of the existing efforts for supporting the design, preparation, and deployment of accessible e-learning applications propose guidelines that primarily address technical accessibility issues. Little, if any, consideration is given to the real actors involved in the learning experience, such as didactical experts and disabled learners. Moreover, implementing artifacts addressed to the e-learning world requires a wide range of particular skills which are related not only to technical but also to didactical, pedagogical, usability, and accessibility aspects of the produced material. This paper argues that the know-how of a number of stakeholders should be blended into a joint design activity, and that it should be possible to determine the role of each participant in the successive phases of the development lifecycle of e-learning applications. The paper sketches the methodological guidelines of a design framework based on involving the users with disabilities, as well as pedagogical experts, in the development process. The novelty of this proposal mainly stems from being built up around the core of strategies and choices specifically bound to accessibility requirements. Characteristic elements of learner-centered design are then further integrated into processes and methodologies which are typical of participatory and contextual design approaches. Following such guidelines, it will be possible to gain a deeper understanding of the requirements and of the operational context of people needing accessible material, either as learners or educators. The underlying objective is to increase the potential to realize learning systems that better meet different user needs and that provide a more satisfying learning experience. Moreover, when people get involved in the development process, they gain a sense of ownership of the system and are therefore more likely to accept and “promote” it.

Engaging Families in Lifestyle Changes Through Social Networking

Previous research has shown that providing family engagement and social support play important roles in weight management success, helping to achieve long-term lifestyle changes. Traditionally, the support provided by online health communities is primarily targeted at individuals and does not involve their families. SOFA (SOcial FAmilies), a novel approach for engaging, motivating, and persuading families to adopt a healthy lifestyle, is proposed. SOFA is an online social network for families coupled with a repository of health-related educational content. This article reports the results of a live user study aimed at investigating how user profile representation and system-assigned tasks influence users engagement with the system and change their attitude toward a healthy lifestyle. The results show that representing family members as individuals increases the number of active members per family as well as their retention, contribution to, and engagement with the network. The results also show that family-based social networks positively change the attitude of family members toward a healthy lifestyle.

Improving health information access through social networking

Sustaining user participation is a challenge for even the most popular web sites. In this work we report on an effort to increase exposure to, and interaction with, a repository of health based information by coupling the repository with a social networking application. We hypothesize that we can sustain user interaction with a repository and increase nutrition knowledge through content browsing by reporting on the browsing actions of other users in a Social Networking Systems activity feeds. We report on the findings of a live user study, which showed that coupling health content with a social networking system successfully increased content browsing and that highly engaged users are seen to have an altered attitude toward control over their health.

Supporting cognitive walkthrough with video data: a mobile learning evaluation study

Although expert-based evaluation techniques such as heuristic evaluation and cognitive walkthrough are often inexpensive and quick to apply, they have not proved to be effective in capturing contextual factors that arise in real-world settings. It is no trivial issue to understand how such evaluation techniques could be modified or differently applied so as to better take into account context, without loosing the advantages inherent in those techniques. This paper explores a possible way of addressing the trade-off between application of cognitive walkthrough and low cost improvements of its contextual validity. In particular, we propose and investigate the benefits of supporting cognitive walkthrough with video data about user interaction with an eLearning course on mobile device. Initial results from this study indicated that video data provided evaluators with a more detailed understanding of user characteristics and interaction contexts, leading to an improvement of their assessments in terms of the total number of systems flaws detected. Video data was regarded by experts as both relevant and useful, especially for tuning the evaluation focus on types of difficulties they would normally not have experienced because of differences in terms of abilities, knowledge and background with those of the target user group.

Personalized techniques for lifestyle change

Online delivery of lifestyle intervention programs offers the potential to cost effectively reach large cohorts of users with various information and dietary needs. Unfortunately, online systems can fail to engage users in the long term, affecting their ability to sustain positive lifestyle change. In this work we present the initial analysis of a large scale application study of personalized technologies for lifestyle change. We evaluate the stickiness of an eHealth portal which provides individuals with three personalized tools - meal planner, social network feeds, and social comparison - to make change a reality in their lives. More than 5000 Australians took part in a 12 week study and provided solid empirical evidence for how the inclusion of personalized tools can assist and motivate users. Initial results show that the personalized tools boost user interaction with the portal, simplify information access, and assist in motivating users.

SOFA: an online social network for engaging and motivating families to adopt a healthy lifestyle

Overweight and obesity have become a global epidemic and are increasing rapidly. Previous research has shown that providing social support and family support has profound roles on the weight management of individuals. However, the support provided by online health communities is outside the family context and is targeted at individuals. We are proposing SOFA (SOcial FAmily), an online social networking system aimed to engage and motivate families to adopt a healthy lifestyle through exposure to educational information on diet exercise and a range of other healthy living information. In this paper, we describe SOFAs features, the research questions that we are investigating and some preliminary results from a live deployment. The results showed that adding a social layer can considerably increase user engagement with static educational content and showed that the provision of family based profiles reduced the activity levels of individual family members when compared to those with individual profiles.

Design, realization and user evaluation of the SmartVortex Visual Query System for accessing data streams in industrial engineering applications

Objective: In this paper we present a Visual Query System, which allows users to graphically build queries over data streams and traditional relational data. The Visual Query System runs on top of a DSMS (Data Stream Management System).Methods: The system has been designed and implemented following the user-centered design approach. Two different releases of the system have been incrementally and iteratively designed and evaluated. The first release has been evaluated using heuristic evaluation. The second release, whose design was a refinement based on the results of the foregoing heuristic evaluation, was evaluated by several users. Moreover, a comparative evaluation involving users has been conducted on the second release.Results: The paper presents the visual query system, and the results ofthe various evaluations.Conclusion: Visual Query Systems for data streams are an effective tool for industrial engineers in querying and analyzing data streams from equipments.Practice and implications: The proposed visual query system has been employed in real industrial scenarios in order to visually query and analyze data streams produced by industrial machines. HighlightsWe investigated the issues of visually querying data streams.We developed a Visual Query System for a real data stream management.We evaluated such a system with an usability study in two phases, and compared with state-of-the-art tools.We report the evaluation results.