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IJHCS Tables of Contents: 555657585960616263646566676869707172

International Journal of Human-Computer Studies 65

Editors:Enrico Motta; Susan Wiedenbeck
Publisher:Elsevier Science Publishers
Standard No:ISSN 0020-7373; TA 167 A1 I5
Links:Table of Contents
  1. IJHCS 2007 Volume 65 Issue 1
  2. IJHCS 2007 Volume 65 Issue 2
  3. IJHCS 2007 Volume 65 Issue 3
  4. IJHCS 2007 Volume 65 Issue 4
  5. IJHCS 2007 Volume 65 Issue 5
  6. IJHCS 2007 Volume 65 Issue 6
  7. IJHCS 2007 Volume 65 Issue 7
  8. IJHCS 2007 Volume 65 Issue 8
  9. IJHCS 2007 Volume 65 Issue 9
  10. IJHCS 2007 Volume 65 Issue 10
  11. IJHCS 2007 Volume 65 Issue 11
  12. IJHCS 2007 Volume 65 Issue 12

IJHCS 2007 Volume 65 Issue 1

Information security in the knowledge economy BIBFull-Text 1-2
  Ajay S. Vinze; T. S. Raghu
Worm damage minimization in enterprise networks BIBAKFull-Text 3-16
  Surasak Sanguanpong; Urupoj Kanlayasiri
Attackers utilize many forms of intrusion via computer networks; currently, worms are an important vector with the potential for widespread damage. None of the strategies is effective and rapid enough to mitigate worm propagation. Therefore, it is extremely important for organizations to better understand worm behaviour and adopt a strategy to minimize the damage due to worm attacks. This paper describes an approach to minimize the damage due to worm infection in enterprise networks. The approach includes: (1) analyzing the effect of parameters influencing worm infection: openness, homogeneity, and trust, (2) predicting the number of infected nodes by fuzzy decision, and (3) optimizing the trust parameter to minimize the damage by fuzzy control. Experiments using real worm attacks show that the selected parameters are strongly correlated with actual infection rates, the damage prediction produces accurate estimates, and the optimization of the selected parameter can lessen the damage from worm infection.
Keywords: Worm; Worm infection; Fuzzy decision; Fuzzy control; Network security
The usability of passphrases for authentication: An empirical field study BIBAKFull-Text 17-28
  Mark Keith; Benjamin Shao; Paul John Steinbart
In developing password policies, IT managers must strike a balance between security and memorability. Rules that improve structural integrity against attacks may also result in passwords that are difficult to remember. Recent technologies have relaxed the 8-character password constraint to permit the creation of longer pass-"phrases" consisting of multiple words. Longer passphrases are attractive because they can improve security by increasing the difficulty of brute-force attacks and they might also be easy to remember. Yet, no empirical evidence concerning the actual usability of passphrases exists. This paper presents the results of a 12-week experiment that examines users' experience and satisfaction with passphrases. Results indicate that passphrase users experienced a rate of unsuccessful logins due to memory recall failure similar to that of users of self-generated simple passwords and stringent passwords. However, passphrase users had more failed login attempts due to typographical errors than did users of either simple or highly secure passwords. Moreover, although the typographical errors disappeared over time, passphrase users' initial problems negatively affected their end-of-experiment perceptions.
Keywords: Passwords; Passphrases; Authentication; Security; Memory; Usability
Investigation of IS professionals' intention to practise secure development of applications BIBAKFull-Text 29-41
  Irene M. Y. Woon; Atreyi Kankanhalli
It is well known that software errors may lead to information security vulnerabilities, the breach of which can have considerable negative impacts for organizations. Studies have found that a large percentage of security defects in e-business applications are due to design-related flaws, which could be detected and corrected during applications development. Traditional methods of managing software application vulnerabilities have often been ad hoc and inadequate. A recent approach that promises to be more effective is to incorporate security requirements as part of the application development cycle. However, there is limited practice of secure development of applications (SDA) and lack of research investigating the phenomenon.
   Motivated by such concerns, the goal of this research is to investigate the factors that may influence the intention of information systems (IS) professionals to practise SDA, i.e., incorporate security as part of the application development lifecycle. This study develops two models based on the widely used theory of planned behaviour (TPB) and theory of reasoned action (TRA) to explain the phenomenon. Following model operationalization, a field survey of 184 IS professionals was conducted to empirically compare the explanatory power of the TPB-based model versus the TRA-based model.
   Consistent with TPB and TRA predictions, attitude and subjective norm were found to significantly impact intention to practise SDA for the overall survey sample. Attitude was in turn determined by product usefulness and career usefulness of SDA, while subjective norm was determined by interpersonal influence, but not by external influence. Contrary to TPB predictions, perceived behavioural controls, conceptualized in terms of self-efficacy and facilitating conditions, had no significant effect on intention to practise SDA. Thus, a modified TRA-based model was found to offer the best explanation of behavioural intention to practise SDA. Implications for research and information security practice are suggested.
Keywords: Secure development of applications; Theory of planned behaviour; Theory of reasoned action; Information security
Mapping the contemporary terrorism research domain BIBAKFull-Text 42-56
  Edna F. Reid; Hsinchun Chen
A systematic view of terrorism research to reveal the intellectual structure of the field and empirically discern the distinct set of core researchers, institutional affiliations, publications, and conceptual areas can help us gain a deeper understanding of approaches to terrorism. This paper responds to this need by using an integrated knowledge-mapping framework that we developed to identify the core researchers and knowledge creation approaches in terrorism. The framework uses three types of analysis: (a) basic analysis of scientific output using citation, bibliometric, and social network analyses, (b) content map analysis of large corpora of literature, and (c) co-citation analysis to analyse linkages among pairs of researchers. We applied domain visualization techniques such as content map analysis, block-modeling, and co-citation analysis to the literature and author citation data from the years 1965 to 2003. The data were gathered from ten databases such as the ISI Web of Science. The results reveal: (1) the names of the top 42 core terrorism researchers (e.g., Brian Jenkins, Bruce Hoffman, and Paul Wilkinson) as well as their institutional affiliations; (2) their influential publications; (3) clusters of terrorism researchers who work in similar areas; and (4) that the research focus has shifted from terrorism as a low-intensity conflict to a strategic threat to world powers with increased focus on Osama Bin Laden.
Keywords: Terrorism; Visualization; Bibliometrics; Co-citation analysis; Intellectual structure
Mining communities and their relationships in blogs: A study of online hate groups BIBAKFull-Text 57-70
  Michael Chau; Jennifer Xu
Blogs, often treated as the equivalence of online personal diaries, have become one of the fastest growing types of Web-based media. Everyone is free to express their opinions and emotions very easily through blogs. In the blogosphere, many communities have emerged, which include hate groups and racists that are trying to share their ideology, express their views, or recruit new group members. It is important to analyze these virtual communities, defined based on membership and subscription linkages, in order to monitor for activities that are potentially harmful to society. While many Web mining and network analysis techniques have been used to analyze the content and structure of the Web sites of hate groups on the Internet, these techniques have not been applied to the study of hate groups in blogs. To address this issue, we have proposed a semi-automated approach in this research. The proposed approach consists of four modules, namely blog spider, information extraction, network analysis, and visualization. We applied this approach to identify and analyze a selected set of 28 anti-Blacks hate groups (820 bloggers) on Xanga, one of the most popular blog hosting sites. Our analysis results revealed some interesting demographical and topological characteristics in these groups, and identified at least two large communities on top of the smaller ones. The study also demonstrated the feasibility in applying the proposed approach in the study of hate groups and other related communities in blogs.
Keywords: Blogs; Social network analysis; Hate groups; Web mining
Analyzing terror campaigns on the internet: Technical sophistication, content richness, and Web interactivity BIBAKFull-Text 71-84
  Jialun Qin; Yilu Zhou; Edna Reid; Guanpi Lai; Hsinchun Chen
Terrorists and extremists are increasingly utilizing Internet technology to enhance their ability to influence the outside world. Due to the lack of multi-lingual and multimedia terrorist/extremist collections and advanced analytical methodologies, our empirical understanding of their Internet usage is still very limited. To address this research gap, we explore an integrated approach for identifying and collecting terrorist/extremist Web contents. We also propose a Dark Web Attribute System (DWAS) to enable quantitative Dark Web content analysis from three perspectives: technical sophistication, content richness, and Web interactivity. Using the proposed methodology, we identified and examined the Internet usage of major Middle Eastern terrorist/extremist groups. More than 200,000 multimedia Web documents were collected from 86 Middle Eastern multi-lingual terrorist/extremist Web sites. In our comparison of terrorist/extremist Web sites to US government Web sites, we found that terrorists/extremist groups exhibited similar levels of Web knowledge as US government agencies. Moreover, terrorists/extremists had a strong emphasis on multimedia usage and their Web sites employed significantly more sophisticated multimedia technologies than government Web sites. We also found that the terrorists/extremist groups are as effective as the US government agencies in terms of supporting communications and interaction using Web technologies. Advanced Internet-based communication tools such as online forums and chat rooms are used much more frequently in terrorist/extremist Web sites than government Web sites. Based on our case study results, we believe that the DWAS is an effective tool to analyse the technical sophistication of terrorist/extremist groups' Internet usage and could contribute to an evidence-based understanding of the applications of Web technologies in the global terrorism phenomena.
Keywords: Web content analysis; Web usage analysis; Web collection building
Stochastic dynamics of music album lifecycle: An analysis of the new market landscape BIBAKFull-Text 85-93
  Sudip Bhattacharjee; Ram D. Gopal; Kaveepan Lertwachara; James R. Marsden
The rapid emergence of file sharing networks has enabled easier information dissemination and product access to potential consumers. At the same time, copyright protection technologies for securing digital products have been compromised repeatedly. To analyze the ensuing impacts on the market landscape for music products (a digital good), we develop a stochastic model of distribution of music album longevity on the Billboard Chart. We find that since the advent of file sharing networks and other market forces (such as legal changes in copyright laws, introduction of digital rights management systems and legitimate online music download offerings), the lifecycle of music albums has shortened with lowered probabilities of survival for each week. While the probability of survival past the first week is markedly lower, the future portends well for albums that do survive on the charts beyond the first week. This is consistent with the rapid diffusion of information on music albums in the changed market landscape. Integrating this insight with user activity on online computer networks, we estimate the continued success of albums on the charts. This analysis helps to create a more dynamic decision process on resource allocation to promote and market music products. Using the robust stochastic model parameters as a benchmark, we estimate a logistic regression model which helps us make quality decisions in an uncertain environment through early monitoring of the success of music albums.
Keywords: Lifecycle; Intellectual property rights; Ranking chart

IJHCS 2007 Volume 65 Issue 2

Design and evaluation of visualization support to facilitate decision trees classification BIBAKFull-Text 95-110
  Yan Liu; Gavriel Salvendy
The loosely coupled relationships between visualization and analytical data mining (DM) techniques represent the majority of the current state of art in visual data mining; DM modeling is typically an automatic process with very limited forms of guidance from users. A conceptual model of the visualization support to DM modeling process and a novel interactive visual decision tree (IVDT) classification process have been proposed in this paper, with the aim of exploring humans' pattern recognition ability and domain knowledge to facilitate the knowledge discovery process. An IVDT for categorical input attributes has been developed and experimented on 20 subjects to test three hypotheses regarding its potential advantages. The experimental results suggested that, compared to the automatic modeling process as typically applied in current decision tree modeling tools, IVDT process can improve the effectiveness of modeling in terms of producing trees with relatively high classification accuracies and small sizes, enhance users' understanding of the algorithm, and give them greater satisfaction with the task.
Keywords: Visual data mining; Interactive modeling; Model visualization; Data visualization
The media equation and team formation: Further evidence for experience as a moderator BIBAKFull-Text 111-124
  Daniel Johnson; John Gardner
This study extends previous media equation research, which showed that interdependence but not identity leads to team affiliation effects with computers. The current study used an identity manipulation that more closely replicated the manipulation used in traditional team and group formation research than the original media equation research in this area. The study also sought further evidence for the relationship between experience with computers and behaviour reflecting a media equation pattern of results. Sixty students from the University of Queensland voluntarily participated in the study. Participants were assigned to one of three conditions: control, human team (a team made of only humans) or human-computer team (a team made of computers and humans). Questionnaire measures assessing participants' affective experience, attitudes and opinions were taken. Participants of high experience with computers, but not low experience, when assigned to either of the team conditions enjoyed the tasks completed on the computer more than participants who worked on their own. When assigned to a team that involved a computer, participants of high experience, but not low experience, reacted negatively towards the computer (in comparison to high experience participants working on their own or on a team without a computer as a team member) -- rating the information provided by the computer lower, rating themselves as less influenced by the computer and changing their own ratings and rankings to be less like those of the computer. These results are interpreted in light of the 'Black Sheep' literature and recognized as a media equation pattern of results.
Keywords: Media equation; Team formation; Groups; Experience; Human computer interaction
CourseVis: A graphical student monitoring tool for supporting instructors in web-based distance courses BIBAKFull-Text 125-139
  Riccardo Mazza; Vania Dimitrova
This paper presents CourseVis, a system that takes a novel approach of using Web log data generated by course management systems (CMSs) to help instructors become aware of what is happening in distance learning classes. Specifically, techniques from information visualization (IV) are employed to graphically render complex, multidimensional student tracking data. Several graphical representations are generated to help distance learning instructors get a better understanding of social, behavioural, and cognitive aspects related to learners. The evaluation of CourseVis shows that it can help instructors to quickly identify tendencies in their classes and discover individuals that might need special attention. This suggests that the effectiveness of CMSs can be improved by integrating IV techniques to generate appropriate graphical representations, similar to those produced in CourseVis.
Keywords: Web-based distance education; Student tracking; Information visualization
Developing professional skills and social capital through computer supported collaborative learning in university contexts BIBAKFull-Text 140-152
  Donata Francescato; Minou Mebane; Rita Porcelli; Carlo Attanasio; Marcella Pulino
This study aimed to compare the efficacy of collaborative learning in face-to-face and online university courses in developing professional skills and social capital. One hundred and sixty-six psychology majors learnt professional skills in seminars taught by the same teacher online and face-to-face. The different groups of participants achieved similar growth in level of professional knowledge, social self-efficacy, self-efficacy for problem solving and empowerment. Instead, online students were top performers on competence-based tasks. Follow-up evaluation after 9 months showed that social ties, formed initially more in the face-to-face groups, lasted more among online students. Our results indicate that Computer Assisted Collaborative Learning could provide educational opportunities to new groups of learners as well as to more traditional campus-based students.
Keywords: Collaborative learning; E-learning; Distance education; CSCL; Social interaction; Small groups; Self-efficacy; Social capital; Empowerment
Knowledge sharing behavior in virtual communities: The relationship between trust, self-efficacy, and outcome expectations BIBAKFull-Text 153-169
  Meng-Hsiang Hsu; Teresa L. Ju; Chia-Hui Yen; Chun-Ming Chang
There has been a growing interest in examining the factors that support or hinder one's knowledge sharing behavior in the virtual communities. However, still very few studies examined them from both personal and environmental perspectives. In order to explore the knowledge sharing behaviors within the virtual communities of professional societies, this study proposed a social cognitive theory (SCT)-based model that includes knowledge sharing self-efficacy and outcome expectations for personal influences, and multi-dimensional trusts for environmental influences. The proposed research model was then evaluated with structural equation modeling, and confirmatory factor analysis was also applied to test if the empirical data conform to the proposed model.
Keywords: Knowledge sharing behavior; Trust; Self-efficacy; Social cognitive theory; Virtual communities
A cyclic model of information seeking in hyperlinked environments: The role of goals, self-efficacy, and intrinsic motivation BIBAKFull-Text 170-182
  Prabu David; Mei Song; Andrew Hayes; Eric S. Fredin
To examine the emergent properties of information seeking in hyperlinked environments, in this paper we developed a cyclic model. Using this model as a framework, the relationships among perceived goal difficulty, goal success, and self-efficacy were examined. Self-efficacy was conceptualized as a mediating mechanism and intrinsic motivation (IM) in the task was examined as a moderator. Data were collected as repeated measures over 20 cycles during an hour-long session of information seeking when students were given that task of designing a travel plan for a trip to China. The findings suggest that success in meeting information goals in one cycle resulted in an increase in self-efficacy, which in turn reduced the perceived difficulty of information goals in the upcoming cycle. At the same time, self-efficacy from previous cycles seemed to provide the impetus for formulating more challenging information goals in subsequent cycles. Besides this dual role of self-efficacy, the moderating role of IM was also evident. For participants relatively high in baseline IM for the task, the link between self-efficacy and goal success was weaker. However, for participants with relatively low levels of baseline IM for the task, goal success has a stronger effect on self-efficacy.
Keywords: Computer self-efficacy; Information search; Goal-setting; Human-computer interaction; Information seeking; Information retrieval; Intrinsic motivation; Social cognitive theory

IJHCS 2007 Volume 65 Issue 3

Is happy better than sad even if they are both non-adaptive? Effects of emotional expressions of talking-head interface agents BIBAKFull-Text 183-191
  Li Gong
Hedonic preference and contextual appropriateness are two general principles governing humans' emotional expressions. People in general prefer perceiving and expressing positive emotions to negative ones, but also modulate their emotional expressions to be appropriate to social contexts. Although computer-based characters such as interface agents are able to express basic human emotions, they cannot yet automatically and effectively adapt their emotional expressions to the changing context. Would hedonic preference hold up without contextual appropriateness? A 2x2 mixed-design experiment (happy vs. sad expression by happy vs. sad context) (N=24) was conducted with a talking-head agent presenting happy and sad novels to users. Supporting the hedonic preference principle, results showed that although both happy and sad agents were non-adaptive to the varying emotional tone of the context, the happy agent elicited greater intent to consume the books, more positive evaluation of the book reviews, more positive attitudes towards the agent and the interface, and more positive user experience than the sad agent.
Keywords: Interface agents; Talking-heads; Emotional expressions; Faces; Voices; Hedonic preference; Happy; Sad
Making adaptive cruise control (ACC) limits visible BIBAKFull-Text 192-205
  Bobbie D. Seppelt; John D. Lee
Previous studies have shown adaptive cruise control (ACC) can compromise driving safety when drivers do not understand how the ACC functions, suggesting that drivers need to be informed about the capabilities of this technology. This study applies ecological interface design (EID) to create a visual representation of ACC behavior, which is intended to promote appropriate reliance and support effective transitions between manual and ACC control. The EID display reveals the behavior of ACC in terms of time headway (THW), time to collision (TTC), and range rate. This graphical representation uses emergent features that signal the state of the ACC. Two failure modes -- exceedance of braking algorithm limits and sensor failures -- were introduced in the driving contexts of traffic and rain, respectively. A medium-fidelity driving simulator was used to evaluate the effect of automation (manual, ACC control), and display (EID, no display) on ACC reliance, brake response, and driver intervention strategies. Drivers in traffic conditions relied more appropriately on ACC when the EID display was present than when it was not, proactively disengaging the ACC. The EID display promoted faster and more consistent braking responses when braking algorithm limits were exceeded, resulting in safe following distances and no collisions. In manual control, the EID display aided THW maintenance in both rain and traffic conditions, reducing the demands of driving and promoting more consistent and less variable car-following performance. These results suggest that providing drivers with continuous information about the state of the automation is a promising alternative to the more common approach of providing imminent crash warnings when it fails. Informing drivers may be more effective than warning drivers.
Keywords: EID; ACC; Reliance; Automation failure; Collision warnings
Visual sensitivities of dynamic graphical displays BIBAKFull-Text 206-222
  Munira Jessa; Catherine M. Burns
Advanced display design, such as Ecological Interface Design (EID), makes extensive use of complex graphical objects. Research has shown that by following EID methodologies, supervisory operators have better performance with the EID displays than with non-EID displays. However, the effect of particular dynamic graphical objects seen in EID displays has never been studied. In this study, we examined how different visual features of graphical objects affect the performance of the objects. We used a modified dynamic just noticeable difference task to investigate the graphical objects that show changes most sensitively. We also investigated the sensitivities of graphical objects in determining target levels, directional changes, and proportions. A commercial EID design company generated the graphical objects examined. We had subjects perform four tasks with graphical objects that varied in their visual features but were still representative of objects currently being used in ecological design. It was found that for simple dynamic objects such as bars and polygon objects, a line changing in angle was the most noticeable emergent feature to show a departure from "normal" state. For complex graphical objects, those target-indicator displays that mimic a "bull's eye" when at the target value should be used for displays that show observers when a target value has been reached. Abrupt changes in shape should be used in trend meters to show when variables or processes have changed direction. Finally, "solid objects" that make use of vertical lines and shading should be used for comparison meters that compare two values and keep them in a particular ratio. The findings provide guidance for designers of dynamic advanced graphical displays by encouraging the consideration of visual aspects of graphical objects, as well as prescribing graphical objects that should be used in the types of tasks investigated.
Keywords: Ecological interface design; Graphical displays
ERP training with a web-based electronic learning system: The flow theory perspective BIBAKFull-Text 223-243
  Duke Hyun Choi; Jeoungkun Kim; Soung Hie Kim
Whilst the importance of end-user training is recognized as a factor in the success of information systems, companies have suffered from relatively low information system training budgets and an insufficient number of trainers. However, technological innovations in computers, telecommunications and the Internet, e-learning has made it possible to overcome many constraints. In this study, we suggest an e-learning success model based on flow theory. A questionnaire-based empirical study was used to test the model. It used data from e-learners who participated in a program on Enterprise Resource Planning training with a web-based e-learning system supported by the Korea Ministry of Information and Communication. Results confirm the significant interdependent relationships between the characteristics of e-learning, flow experience, learners' attitude towards e-learning, and the resulting learning outcomes. In particular, it was revealed that flow experience plays a critical role as a central part of our research model, having direct and indirect impact on learning outcomes (i.e., the technology self-efficacy in ERP system usage in this study). This study should be of relevance to both researchers and practitioners alike, as a step towards a better understanding of e-learning, especially in the context of information system training.
Keywords: E-learning; Flow theory; End-user training; ERP
Re-using digital narrative content in interactive games BIBAKFull-Text 244-272
  Annika Wolff; Paul Mulholland; Zdenek Zdrahal; Richard Joiner
This paper presents a model, called Scene-Driver, for the re-use of film and television material. We begin by exploring general issues surrounding the ways in which content can be sub-divided into meaningful units for re-use and how criteria might then be applied to the selection and ordering of these units. We also identify and discuss the different means by which a user might interact with the content to create novel and engaging experiences. The Scene-Driver model has been instantiated using content from an animated children's television series called Tiny Planets, which is aimed at children of 5-7-year old. This type of material, being story-based itself, lends itself particularly well to the application of narrative constraints to scene reordering, to provide coherence to the experience of interacting with the content.
   We propose an interactive narrative-driven game architecture, in which a user generates novel narratives from existing content by placing "domino" like tiles. These tiles act as "glue" between scenes and each tile choice dictates certain properties of the next scene to be shown within a game. There are three different game-types, based on three different ways in which tiles can be matched to scenes. We introduce algorithms for generating legal tile-sets for each of these three game-types, which can be extended to include narrative constraints. This ensures that all novel orderings adhere to a minimum narrative plan, which has been identified based on analysis of the Tiny Planets series and on narrative theories. We also suggest ways in which basic narratives can be enhanced by the inclusion of directorial techniques and by the use of more complex plot structures. In our evaluation studies with children in the target age-range, our game compared favourably with other games that the children enjoyed playing.
Keywords: Interactive narrative; Content reordering; Interface; AI planning algorithms

IJHCS 2007 Volume 65 Issue 4

Evaluating affective interactions BIBFull-Text 273-274
  Katherine Isbister; Kristina Höök
How emotion is made and measured BIBAKFull-Text 275-291
  Kirsten Boehner; Rogério DePaula; Paul Dourish; Phoebe Sengers
How we design and evaluate for emotions depends crucially on what we take emotions to be. In affective computing, affect is often taken to be another kind of information -- discrete units or states internal to an individual that can be transmitted in a loss-free manner from people to computational systems and back. While affective computing explicitly challenges the primacy of rationality in cognitivist accounts of human activity, at a deeper level it often relies on and reproduces the same information-processing model of cognition. Drawing on cultural, social, and interactional critiques of cognition which have arisen in human-computer interaction (HCI), as well as anthropological and historical accounts of emotion, we explore an alternative perspective on emotion as interaction: dynamic, culturally mediated, and socially constructed and experienced. We demonstrate how this model leads to new goals for affective systems -- instead of sensing and transmitting emotion, systems should support human users in understanding, interpreting, and experiencing emotion in its full complexity and ambiguity. In developing from emotion as objective, externally measurable unit to emotion as experience, evaluation, too, alters focus from externally tracking the circulation of emotional information to co-interpreting emotions as they are made in interaction.
Keywords: Affective computing; Affective evaluation
Cultural commentators: Non-native interpretations as resources for polyphonic assessment BIBAKFull-Text 292-305
  William Gaver
Designs for everyday life must be considered in terms of the many facets of experience they affect, including their aesthetics, emotional effects, genre, social niche, and cultural connotations. In this paper, I discuss the use of cultural commentators, people whose profession it is to inform and shape public opinion, as resources for multi-layered assessments of designs for everyday life. I describe our work with a team of movie screenwriters to help interpret the results of a Cultural Probe study, and with film-makers to document the experiences of people living with prototype designs in their homes. The value of employing cultural commentators is that they work outside our usual community of discourse, and are often accustomed to reflecting issues of aesthetics, emotions, social fit or cultural implication that are difficult to address from traditional HCI perspectives. They help to focus and articulate people's accounts of their experiences, extrapolating narratives from incomplete information, and dramatising relationships to create powerful and provocative stories. In so doing, they create the grounds for a polyphonic assessment of prototypes, in which a multiplicity of perspectives encourages a multi-layered assessment.
Keywords: Evaluation; Interaction design; Domestic technologies; Ubiquitous computing; Cultural commentators
Measuring emotional valence to understand the user's experience of software BIBAKFull-Text 306-314
  Richard L. Hazlett; Joey Benedek
This paper reports on the results of two studies that used facial electromyography (EMG) measures combined with verbal and performance measures to provide feedback in the software design process on the user's emotional state. The first study assessed 16 participant's emotional responses while they passively viewed mock ups of proposed new operating system features. The second study measured the emotional responses of 15 participants while they actively used one of two versions of a media player. This multimodal assessment method was able to provide a sensitive measure of the desirability of the proposed software features, and a measure of emotional tension and mental effort expended in the interactive tasks.
Keywords: Emotion; User experience; Affecting computing; Software testing methods; Desirability; Physiologic measures
The sensual evaluation instrument: Developing a trans-cultural self-report measure of affect BIBAKFull-Text 315-328
  Katherine Isbister; Kia Höök; Jarmo Laaksolahti; Michael Sharp
In this paper we describe the development and testing of a tool for self-assessment of affect while interacting with computer systems, meant to be used in many cultures. We discuss our research approach within the context of existing cultural, affective and HCI theory, and describe testing of its effectiveness in the US and Sweden.
Keywords: Affect; Culture; Evaluation; Self-report; Nonverbal
A fuzzy physiological approach for continuously modeling emotion during interaction with play technologies BIBAKFull-Text 329-347
  Regan L. Mandryk; M. Stella Atkins
The popularity of computer games has exploded in recent years, yet methods of evaluating user emotional state during play experiences lag far behind. There are few methods of assessing emotional state, and even fewer methods of quantifying emotion during play. This paper presents a novel method for continuously modeling emotion using physiological data. A fuzzy logic model transformed four physiological signals into arousal and valence. A second fuzzy logic model transformed arousal and valence into five emotional states relevant to computer game play: boredom, challenge, excitement, frustration, and fun. Modeled emotions compared favorably with a manual approach, and the means were also evaluated with subjective self-reports, exhibiting the same trends as reported emotions for fun, boredom, and excitement. This approach provides a method for quantifying emotional states continuously during a play experience.
Keywords: Emotion; Affective computing; Fun; Games; Physiology; Galvanic skin response; Electromyography; Heart rate
Modeling and evaluating empathy in embodied companion agents BIBAFull-Text 348-360
  Scott W. McQuiggan; James C. Lester
Affective reasoning plays an increasingly important role in cognitive accounts of social interaction. Humans continuously assess one another's situational context, modify their own affective state accordingly, and then respond to these outcomes by expressing empathetic behaviors. Synthetic agents serving as companions should respond similarly. However, empathetic reasoning is riddled with the complexities stemming from the myriad factors bearing upon situational assessment. A key challenge posed by affective reasoning in synthetic agents is devising empirically informed models of empathy that accurately respond in social situations. This paper presents Care, a data-driven affective architecture and methodology for learning models of empathy by observing human-human social interactions. First, in Care training sessions, one trainer directs synthetic agents to perform a sequence of tasks while another trainer manipulates companion agents' affective states to produce empathetic behaviors (spoken language, gesture, and posture). Care tracks situational data including locational, intentional, and temporal information to induce a model of empathy. At runtime, Care uses the model of empathy to drive situation-appropriate empathetic behaviors. Care has been used in a virtual environment testbed. Two complementary studies investigating the predictive accuracy and perceived accuracy of Care-induced models of empathy suggest that the Care paradigm can provide the basis for effective empathetic behavior control in embodied companion agents.
Relative subjective count and assessment of interruptive technologies applied to mobile monitoring of stress BIBAKFull-Text 361-375
  Rosalind W. Picard; Karen K. Liu
A variety of technologies -- from agents designed to assist or encourage you, to context-based messaging services -- have the opportunity to interrupt you many times throughout the day. One of the challenges with designing new highly interruptive technologies is how to objectively assess their influence on human experience. This paper presents an assessment of a new mobile system that interrupts the wearer to support self-monitoring of stress. We utilize a diverse set of assessment techniques, including a newly proposed measure, relative subjective count, which compares the difference in perceived number of interruptions to actual number of interruptions. This measure, together with direct and indirect subjective reports, and a behavioral choice, is used to evaluate an empathetic version of the mobile system vs. a non-empathetic version. We found that post-experience direct questionnaire assessments such as "how stressful has using the system been?" do not significantly distinguish user experiences with the two systems; however, the new measure of relative subjective count, the behavioral choice, and another indirect questioning strategy, do point toward a preference for the empathetic system.
Keywords: Affective assessment; Relative subjective duration; Frustration measures; Relational computing; Wearable and mobile computing; Ubiquitous computing; Physiological monitoring; Stress monitoring
Communicating emotion through a haptic link: Design space and methodology BIBAKFull-Text 376-387
  Jocelyn Smith; Karon MacLean
Communication of affect across a distance is not well supported by current technology, despite its importance to interpersonal interaction in modern lifestyles. Touch is a powerful conduit for emotional connectedness, and thus mediating haptic (touch) displays have been proposed to address this deficiency; but suitable evaluative methodology has been elusive. In this paper, we offer a first, structured examination of a design space for haptic support of remote affective communication, by analyzing the space and then comparing haptic models designed to manipulate its key dimensions. In our study, dyads (intimate pairs or strangers) are asked to communicate specified emotions using a purely haptic link that consists of virtual models rendered on simple knobs. These models instantiate both interaction metaphors of varying intimacy, and representations of virtual interpersonal distance. Our integrated objective and subjective observations imply that emotion can indeed be communicated through this medium, and confirm that the factors examined influence emotion communication performance as well as preference, comfort and connectedness. The proposed design space and the study results have implications for future efforts to support affective communication using the haptic modality, and the study approach comprises a first model for systematic evaluation of haptically expressed affect.
Keywords: Haptic communication; Affect; Evaluation methodology; Early design
In situ informants exploring an emotional mobile messaging system in their everyday practice BIBAKFull-Text 388-403
  Petra Sundström; Anna Ståhl; Kristina Höök
We have designed and built a mobile emotional messaging system named eMoto. With it, users can compose messages through using emotion-signalling gestures as input, rendering a message background of colours, shapes and animations expressing the emotional content. The design intent behind eMoto was that it should be engaging physically, intellectually and socially, and allow users to express themselves emotionally in all those dimensions, involving them in an affective loop experience. In here, we describe the user-centred design process that lead to the eMoto system, but focus mainly on the final study where we let five friends use eMoto for two weeks. The study method, which we name in situ informants, helped us enter and explore the subjective and distributed experiences of use, as well as how emotional communication unfolds in everyday practice when channelled through a system like eMoto. The in situ informants are on the one hand users of eMoto, but also spectators, that are close friends who observe and document user behaviour. Design conclusions include the need to support the sometimes fragile communication rhythm that friendships require -- expressing memories of the past, sharing the present and planning for the future. We saw that emotions are not singular state that exist within one person alone, but permeates the total situation, changing and drifting as a process between the two friends communicating. We also gained insights into the under-estimated but still important physical, sensual aspects of emotional communication. Experiences of the in situ informants method pointed to the need to involve participants in the interpretation of the data obtained, as well as establishing a closer connection with the spectators.
Keywords: Affective interaction; Evaluation method; User study; Mobile application
Experimental evaluation of five methods for collecting emotions in field settings with mobile applications BIBAKFull-Text 404-418
  Minna Isomursu; Marika Tähti; Soili Väinämö; Kari Kuutti
This paper presents experiences on using five different self-report methods, two adopted from literature and three self-created, for collecting information about emotional responses to mobile applications. These methods were used in nine separate field experiments done in naturalistic settings. Based on our experiments, we can argue that all of these methods can be successfully used for collecting emotional responses to evaluate mobile applications in mobile settings. However, differences can be identified in the suitability of the methods for different research setups. Even though the self-report instruments provide a feasible alternative for evaluating emotions evoked by mobile applications, several challenges were identified, for example, in capturing the dynamic nature of mobile interaction usage situations and contexts. To summarise our results, we propose a framework for selecting and comparing these methods for different usage purposes.
Keywords: Emotions; User experience; Mobile applications

IJHCS 2007 Volume 65 Issue 5

Ambient intelligence: From interaction to insight BIBFull-Text 419-420
  Yang Cai
Supporting serendipity: Using ambient intelligence to augment user exploration for data mining and web browsing BIBAKFull-Text 421-433
  Russell Beale
Serendipity is the making of fortunate discoveries by accident, and is one of the cornerstones of scientific progress. In today's world of digital data and media, there is now a vast quantity of material that we could potentially encounter, and so there is an increased opportunity of being able to discover interesting things. However, the availability of material does not imply that we will be able to actually find it; the sheer quantity of data mitigates against us being able to discover the interesting nuggets.
   This paper explores approaches we have taken to support users in their search for interesting and relevant information. The primary concept is the principle that it is more useful to augment user skills in information foraging than it is to try and replace them. We have taken a variety of artificial intelligence, statistical, and visualisation techniques, and combined them with careful design approaches to provide supportive systems that monitor user actions, garner additional information from their surrounding environment and use this enhanced understanding to offer supplemental information that aids the user in their interaction with the system.
   We present two different systems that have been designed and developed according to these principles. The first system is a data mining system that allows interactive exploration of the data, allowing the user to pose different questions and understand information at different levels of detail. The second supports information foraging of a different sort, aiming to augment users browsing habits in order to help them surf the internet more effectively. Both use ambient intelligence techniques to provide a richer context for the interaction and to help guide it in more effective ways: both have the user as the focal point of the interaction, in control of an iterative exploratory process, working in indirect collaboration with the artificial intelligence components.
   Each of these systems contains some important concepts of their own: the data mining system has a symbolic genetic algorithm which can be tuned in novel ways to aid knowledge discovery, and which reports results in a user-comprehensible format. The visualisation system supports high-dimensional data, dynamically organised in a three-dimensional space and grouped by similarity. The notions of similarity are further discussed in the internet browsing system, in which an approach to measuring similarity between web pages and a user's interests is presented. We present details of both systems and evaluate their effectiveness.
Keywords: Synergistic interaction; Artificial intelligence; Visualisation; Interesting; Knowledge discovery
Visualization of large networks with min-cut plots, A-plots and R-MAT BIBAKFull-Text 434-445
  Deepayan Chakrabarti; Christos Faloutsos; Yiping Zhan
What does a "normal" computer (or social) network look like? How can we spot "abnormal" sub-networks in the Internet, or web graph? The answer to such questions is vital for outlier detection (terrorist networks, or illegal money-laundering rings), forecasting, and simulations ("how will a computer virus spread?").
   The heart of the problem is finding the properties of real graphs that seem to persist over multiple disciplines. We list such patterns and "laws", including the "min-cut plots" discovered by us. This is the first part of our NetMine package: given any large graph, it provides visual feedback about these patterns; any significant deviations from the expected patterns can thus be immediately flagged by the user as abnormalities in the graph. The second part of NetMine is the A-plots tool for visualizing the adjacency matrix of the graph in innovative new ways, again to find outliers. Third, NetMine contains the R-MAT (Recursive MATrix) graph generator, which can successfully model many of the patterns found in real-world graphs and quickly generate realistic graphs, capturing the essence of each graph in only a few parameters. We present results on multiple, large real graphs, where we show the effectiveness of our approach.
Keywords: Min-cut plots; A-plots; R-MAT; Abnormal subgraphs; Graph generator
Perception modeling for human-like artificial sensor systems BIBAKFull-Text 446-459
  Linn Robertsson; Boyko Iliev; Rainer Palm; Peter Wide
In this article we present an approach to the design of human-like artificial systems. It uses a perception model to describe how sensory information is processed for a particular task and to correlate human and artificial perception. Since human-like sensors share their principle of operation with natural systems, their response can be interpreted in an intuitive way. Therefore, such sensors allow for easier and more natural human-machine interaction.
   The approach is demonstrated in two applications. The first is an "electronic tongue", which performs quality assessment of food and water. In the second application we describe the development of an artificial hand for dexterous manipulation. We show that human-like functionality can be achieved even if the structure of the system is not completely biologically inspired.
Keywords: Artificial perceptual systems; Artificial hand; Electronic tongue; Human-based sensors; Passive perception; Active perception; Dexterous manipulation
Berlin Brain-Computer Interface -- The HCI communication channel for discovery BIBAKFull-Text 460-477
  Roman Krepki; Gabriel Curio; Benjamin Blankertz; Klaus-Robert Müller
The investigation of innovative Human-Computer Interfaces (HCI) provides a challenge for future interaction research and development. Brain-Computer Interfaces (BCIs) exploit the ability of human communication and control bypassing the classical neuromuscular communication channels. In general, BCIs offer a possibility of communication for people with severe neuromuscular disorders, such as amyotrophic lateral sclerosis (ALS) or complete paralysis of all extremities due to high spinal cord injury. Beyond medical applications, a BCI conjunction with exciting multimedia applications, e.g., a dexterity discovery, could define a new level of control possibilities also for healthy customers decoding information directly from the user's brain, as reflected in EEG signals which are recorded non-invasively from the scalp.
   This contribution introduces the Berlin Brain-Computer Interface (BBCI) and presents set-ups where the user is provided with intuitive control strategies in plausible interactive bio-feedback applications. Yet at its beginning, BBCI thus adds a new dimension in HCI research by offering the user an additional and independent communication channel based on brain activity only. Successful experiments already yielded inspiring proofs-of-concept. A diversity of interactive application models, say computer games, and their specific intuitive control strategies are now open for BCI research aiming at a further speed up of user adaptation and increase of learning success and transfer bit rates.
   BBCI is a complex distributed software system that can be run on several communicating computers responsible for (i) the signal acquisition, (ii) the data processing and (iii) the feedback application. Developing a BCI system, special attention must be paid to the design of the feedback application that serves as the HCI unit. This should provide the user with the information about her/his brain activity in a way that is intuitively intelligible. Exciting discovery applications qualify perfectly for this role. However, most of these applications incorporate control strategies that are developed especially for the control with haptic devices, e.g., joystick, keyboard or mouse. Therefore, novel control strategies should be developed for this purpose that (i) allow the user to incorporate additional information for the control of animated objects and (ii) do not frustrate the user in the case of a misclassification of the decoded brain signal.
   BCIs are able to decode different information types from the user's brain activity, such as sensory perception or motor intentions and imaginations, movement preparations, levels of stress, workload or task-related idling. All of these diverse brain signals can be incorporated in an exciting discovery scenario. Modern HCI research and development technologies can provide BCI researchers with the know-how about interactive feedback applications and corresponding control strategies.
Keywords: Brain-Computer Interface; Scientific discovery; Electroencephalography; Digital Signal Processing; Machine learning; Bio-feedback; Control strategy; Gaming; Virtual limbs

IJHCS 2007 Volume 65 Issue 6

"Most Cited Paper Award" for the International Journal of Human-Computer Studies BIB 479
Real faces and robot faces: The effects of representation on computer-mediated communication BIBAKFull-Text 480-496
  Emma L. Clayes; Anne H. Anderson
While there is much research regarding audio, video and text based communication, there has been little work concerning how users communicate via avatars -- that is graphical embodiments of remote users. The aim of this study was to explore the effects of different forms of representation, by examining how users communicate via high quality video images and basic graphical representations in different communicative contexts. Communication analysis revealed that video images facilitate turn-taking, although they are not necessarily perceived very differently from basic avatars in terms of questionnaire responses. Using eye-tracking techniques, we found that while participants generally gaze more often at video images, this is dependent on the communicative context and is not necessarily an advantage in a problem-solving situation. This study has demonstrated the value of employing various measures and tasks in order to evaluate computer-mediated interactions. The results have implications for the use of video and graphical representations in computer mediated communication and suggest that the benefits of video must be considered in relation to the user's requirements (e.g. communication process versus outcome) and context in which the system is to be applied (e.g. problem-solving or social).
Keywords: Video-mediated communication; Avatars; Eye-tracking
The effects of agent activeness and cooperativeness on team decision efficiency: A computational simulation study using Team-Soar BIBAFull-Text 497-510
  Mincheol Kang
Within an organizational context, an agent type reflects the behavioral tendency that a member might employ across tasks. Until now, however, the impacts of agent types on team performance are not well understood. To address this issue, this study examines the relationships of agent activeness and cooperativeness with team decision efficiency at different degrees of information redundancy by using a team model consisting of four AI agents. This study presents the team model called "Team-Soar" and describes how the model implements agent activeness at two levels (active and passive) and agent cooperativeness at three levels (cooperative, neutral, and selfish). Then a computational simulation experiment is described. Results of the simulation indicate that the impacts of the agent type depend on the amount of information to be processed and active style boosts the effects of agent cooperativeness on team efficiency. The results also indicate that active agents do not always contribute team efficiency more than passive agents.
A balanced thinking-feelings model of information systems continuance BIBAKFull-Text 511-525
  Hee-Woong Kim; Hock Chuan Chan; Yee Pia Chan
Most studies on technology adoption and usage continuance examine cognitive factors, leaving affective factors or the feelings of users relatively unexplored. In contrast, researchers in the diverse fields of human-computer interaction, medicine, psychology and marketing have begun to note the importance of feelings in understanding and predicting human behavior. Feelings are anticipated to be essential particularly in the context of modern applications, such as mobile Internet (M-Internet) services. Users of modern technology are not simply technology users but also service consumers and may consider both cognitive and emotional benefits. Drawing upon multidisciplinary findings, this study proposes a balanced thinking-feelings model of IS continuance. In the process of developing this model, the concepts of attitude, thinking and feelings are further articulated, defined and distinguished. The balanced thinking-feelings model is validated in a survey of M-Internet service users. To encourage continuance, companies should consider ways to enhance both cognitive and emotional benefits for users. The model could be also useful for balanced understanding of other behaviors.
Keywords: IS continuance; Thinking; Feelings; Mobile internet service
Internet users' perceptions of 'privacy concerns' and 'privacy actions' BIBAKFull-Text 526-536
  Carina Paine; Ulf-Dietrich Reips; Stefan Stieger; Adam Joinson; Tom Buchanan
A consistent finding reported in online privacy research is that an overwhelming majority of people are 'concerned' about their privacy when they use the Internet. Therefore, it is important to understand the discourse of Internet users' privacy concerns, and any actions they take to guard against these concerns. A Dynamic Interviewing Programme (DIP) was employed in order to survey users of an instant messaging ICQ ('I seek you') client using both closed and open question formats. Analysis of 530 respondents' data illustrates the importance of establishing users' privacy concerns and the reasoning behind these concerns. Results indicate that Internet users are concerned about a wider range of privacy issues than surveys have typically covered. The results do not provide final definitions for the areas of online privacy, but provide information that is useful to gain a better understanding of privacy concerns and actions.
Keywords: Privacy; Internet; Survey Methodology; Instant Messaging
Ontologies as facilitators for repurposing web documents BIBAKFull-Text 537-562
  Mark J. Weal; Harith Alani; Sanghee Kim; Paul H. Lewis; David E. Millard; Patrick A. S. Sinclair; David C. De Roure; Nigel R. Shadbolt
This paper investigates the role of ontologies as a central part of an architecture to repurpose existing material from the web. A prototype system called ArtEquAKT is presented, which combines information extraction, knowledge management and consolidation techniques and adaptive document generation.
   All of these components are co-ordinated using one central ontology, providing a common vocabulary for describing the information fragments as they are processed. Each of the components of the architecture is described in detail and an evaluation of the system discussed. Conclusions are drawn as to the effectiveness of such an approach and further challenges are outlined.
Keywords: Knowledge extraction; Ontology population; Narrative generation

IJHCS 2007 Volume 65 Issue 7

Knowledge representation with ontologies: Present challenges -- Future possibilities BIBAKFull-Text 563-568
  Christopher Brewster; Kieron O'Hara
Ontologies have become the knowledge representation medium of choice in recent years for a range of computer science specialities including the Semantic Web, Agents, and Bio-informatics. There has been a great deal of research and development in this area combined with hype and reaction. This special issue is concerned with the limitations of ontologies and how these can be addressed, together with a consideration of how we can circumvent or go beyond these constraints. The introduction places the discussion in context and presents the papers included in this issue.
Keywords: Ontologies; Knowledge representation; Semantic web; Artificial intelligence; Bio-informatics; Agents
Reflections on a medical ontology BIBAKFull-Text 569-582
  Bo Hu; Srinandan Dasmahapatra; David Dupplaw; Paul Lewis; Nigel Shadbolt
In this paper we confront the divide between the ontologies developed from the requirement of comprehensive and general domain coverage and those devised to meet application-specific requirements. While the generalists typically attach philosophical sophistication to their approach, in supposed contrast to the narrow remit chosen by the application-bound knowledge engineers, we would like to indicate that the latter practice can often reflect a multi-faceted rationale, nuanced by the requirements of the domain.
   We demonstrate how the necessity of placing ontology-based systems with the work-practices of domain experts introduces unique demands on design rationales and enforces, often implicitly, a philosophical assessment of the necessary concepts and relations that balance the generality and specificity. Such demands are not addressed by generic approaches to modelling the reality of a domain. Indeed, we articulate the philosophical and practical considerations that we have taken into account when developing an application-specific ontology. We would certainly hope that our experiences can be of help to the development of ontologies in similar applications.
Keywords: Medical ontology; Knowledge representation
Using OWL to model biological knowledge BIBAKFull-Text 583-594
  Robert Stevens; Mikel Egaña Aranguren; Katy Wolstencroft; Ulrike Sattler; Nick Drummond; Matthew Horridge; Alan Rector
Much has been written of the facilities for ontology building and reasoning offered for ontologies expressed in the Web Ontology Language (OWL). Less has been written about how the modelling requirements of different areas of interest are met by OWL-DL's underlying model of the world. In this paper we use the disciplines of biology and bioinformatics to reveal the requirements of a community that both needs and uses ontologies. We use a case study of building an ontology of protein phosphatases to show how OWL-DL's model can capture a large proportion of the community's needs. We demonstrate how Ontology Design Patterns (ODPs) can extend inherent limitations of this model. We give examples of relationships between more than two instances; lists and exceptions, and conclude by illustrating what OWL-DL and its underlying description logic either cannot handle in theory or because of lack of implementation. Finally, we present a research agenda that, if fulfilled, would help ensure OWL's wider take up in the life science community.
Keywords: OWL-DL ontology; Universals; Ontology Design Patterns; Biology; Bioinformatics; Phosphatase
Bridging the gap between the model-driven architecture and ontology engineering BIBAKFull-Text 595-609
  Stephen Cranefield; Jin Pan
Software engineers have many robust commercial tools available to them for creating and manipulating models. Due to the widespread adoption of the Object Management Group (OMG) standards for metamodel definition, model serialisation and programmatic access to models, many of these tools are interoperable. Currently this is not the case for ontology engineering tools. This paper discusses the potential benefits of making the OMG's model-driven architecture (MDA) technology applicable to ontology engineering, and in particular, describes a technique for converting ontologies serialised using the XML metadata interchange (XMI) format to an equivalent representation using the resource description framework (RDF), without any loss of information. The resulting models can then be analysed and transformed using existing RDF tools. The technique is applicable to any ontology modelling language that has its abstract syntax defined using the OMG's meta-object facility (MOF) model.
   This research helps to bridge the gap between the MDA and ontology engineering by providing a technique based on the familiar RDF language for defining transformations between other types of model (such as UML) and ontologies, between different ontology modelling languages, or to modify ontologies without changing the language.
Keywords: Model-driven architecture (MDA); Ontologies; MOF; JMI; RDF; Jena; NetBeans MDR; ODM
Language, logic and ontology: Uncovering the structure of commonsense knowledge BIBAKFull-Text 610-623
  Walid S. Saba
The purpose of this paper is twofold: (i) we argue that the structure of commonsense knowledge must be discovered, rather than invented; and (ii) we argue that natural language, which is the best known theory of our (shared) commonsense knowledge, should itself be used as a guide to discovering the structure of commonsense knowledge. In addition to suggesting a systematic method to the discovery of the structure of commonsense knowledge, the method we propose seems to also provide an explanation for a number of phenomena in natural language, such as metaphor, intensionality, and the semantics of nominal compounds. Admittedly, our ultimate goal is quite ambitious, and it is no less than the systematic 'discovery' of a well-typed ontology of commonsense knowledge, and the subsequent formulation of the long-awaited goal of a meaning algebra.
Keywords: Ontology; Semantics; Commonsense knowledge; Reasoning
The semantic-document approach to combining documents and ontologies BIBAKFull-Text 624-639
  Henrik Eriksson
An ontology is a powerful way of representing knowledge for multiple purposes. There are several ontology languages for describing concepts, properties, objects, and relationships. However, ontologies in information systems are not primarily written for human reading and communication among humans. For many business, government, and scientific purposes, written documents are the primary description and communication media for human knowledge communication. Unfortunately, there is a significant gap between knowledge expressed as textual documents and knowledge represented as ontologies.
   Semantic documents aim at combining documents and ontologies, and allowing users to access the knowledge in multiple ways. By adding annotations to electronic-document formats and including ontologies in electronic documents, it is possible to reconcile documents and ontologies, and to provide new services, such as ontology-based searches of large document databases. To accomplish this goal, semantic documents require tools that support both complex ontologies and advanced document formats. The Protégé ontology editor, together with a custom-tailored documentation-handling extension, enables developers to create semantic documents by linking preexisting documents to ontologies.
Keywords: Document; Ontology; Knowledge representation; Annotation; Metadata
Ontology schema for an agent belief store BIBAKFull-Text 640-658
  K. L. Clark; F. G. McCabe
In this paper we explore the use of a formal ontology as a constraining framework for the belief store of a rational agent. The static beliefs of the agent are the axioms of the ontology. The dynamic beliefs are the descriptions of the individuals that are instances of the ontology classes. The individuals all have a unique identifier, an associated set of named classes to which they are believed to belong, and a set of property values. The ontology axioms act as a schema for the dynamic beliefs. Belief updates not conforming to the axioms lead to either rejection of the update or some other revision of the dynamic belief store to maintain consistency. Partial descriptions are augmented by inferences of property values and class memberships licensed by the axioms.
   For concreteness we sketch how such an ontology based agent belief store could be implemented in a multi-threaded logic programming language with action rules and object oriented programming features called Go!. This language was specifically designed for implementing communicating rational agent applications. We shall see that its logic rules allow us to extend an ontology of classes and properties with rule defined n-ary relations and functions. Its action rules enable us to implement a consistency maintenance system that takes into account justifications for beliefs. The pragmatics of consistency maintenance is an issue not normally considered by the ontology community.
   The paper assumes some familiarity with ontology specification using languages such as OWL DL and its subsets, and with logic programming.
Keywords: Ontology inference; Rational agents; Truth maintenance
Rule identification using ontology while acquiring rules from Web pages BIBAKFull-Text 659-673
  Sangun Park; Jae Kyu Lee
As research on the Semantic Web actively progresses, a more intelligent Web environment is expected in various domains including rule-based systems and intelligent agents. However, rule acquisition is still a bottleneck in the utilization of rule-based systems. To extract rules from Web pages, the framework of eXtensible Rule Markup Language (XRML) has been developed. XRML allows the identification of rules from Web pages and generates rules automatically. However, the knowledge engineer's burden is still high because rule identification requires considerable manual work. In order to reduce the knowledge engineer's burden, we proposed an ontology-based methodology of enhanced rule identification. First, we have designed an ontology OntoRule for automated rule identification. Also, we proposed a procedure of rule identification using OntoRule. Lastly, we showed the performance of our approach with an experiment.
Keywords: Rule identification; Rule acquisition; Ontology; Knowledge acquisition; Ontology engineering; XRML; RuleML; XML
Beyond ontologies: Toward situated representations of scientific knowledge BIBAKFull-Text 674-688
  William Pike; Mark Gahegan
In information systems that support knowledge-discovery applications such as scientific exploration, reliance on highly structured ontologies as data-organization aids can be limiting. With current computational aids to science work, the human knowledge that creates meaning out of analyses is often only recorded when work reaches publication -- or worse, left unrecorded altogether -- for lack of an ontological model for scientific concepts that can capture knowledge as it is created and used. We argue for an approach to representing scientific concepts that reflects (1) the situated processes of science work, (2) the social construction of knowledge, and (3) the emergence and evolution of understanding over time. In this model, knowledge is the result of collaboration, negotiation, and manipulation by teams of researchers. Capturing the situations in which knowledge is created and used helps these collaborators discover areas of agreement and discord, while allowing individual inquirers to maintain different perspectives on the same information. The capture of provenance information allows historical trails of reasoning to be reconstructed, allowing end users to evaluate the utility and trustworthiness of knowledge representations. We present a proof-of-concept system, called Codex, based on this situated knowledge model. Codex supports visualization of knowledge structures through concept mapping, and enables inference across those structures. The proof-of-concept is deployed in the domain of geoscience to support distributed teams of learners and researchers.
Keywords: Knowledge representation; Situated cognition; Concept maps; Collaboration; Web applications

IJHCS 2007 Volume 65 Issue 8

Manipulating perceived social presence through the web interface and its impact on attitude towards online shopping BIBAKFull-Text 689-708
  Khaled Hassanein; Milena Head
Electronic commerce typically lacks human warmth and sociability, since it is more impersonal, anonymous and automated than traditional face-to-face commerce. This paper explores how human warmth and sociability can be integrated through the web interface to positively impact consumer attitudes towards online shopping. An empirical study was undertaken to investigate the impact of various levels of socially rich text and picture design elements on the perception of online social presence and its subsequent effect on antecedents of attitudes towards websites. Higher levels of perceived social presence are shown to positively impact the perceived usefulness, trust and enjoyment of shopping websites, leading to more favourable consumer attitudes. Implications of these finding for practitioners and future research are outlined.
Keywords: E-commerce; Social presence; Web interface; Online trust; Tam; Enjoyment
Key factors of heuristic evaluation for game design: Towards massively multi-player online role-playing game BIBAKFull-Text 709-723
  Seungkeun Song; Joohyeon Lee
The computer game industry has become the fastest growing field of the entertainment industry. However, only a very small number of computer game products overcome the costs of production and generate earnings. According to traditional marketing wisdom, customers' preferences must be analyzed correctly to create successful products, and in the gaming industry, such information must be considered during the design process. This research aims to explore key factors of heuristic evaluation for game design. A review of literature pertaining to computer games and HCI was conducted along with an empirical research of a Massively Multi-player Online Role-playing Game (MMORPG). We identified 18 usability issues in MMORPG and presented a recommendation relevant to the issues. Empirical data were applied to a new heuristic evaluation framework. We determined the relationship between key factors and four game categories, such as game interface, game play, game narrative, and game mechanics. Moreover, the results presented 54 key factors for a new heuristic evaluation framework for game design. The conclusion presents key implications of our research in a game design context, particularly related to early design processes.
Keywords: MMORPG game design; Usability; Heuristics evaluation; Design process
Automatic prediction of frustration BIBAKFull-Text 724-736
  Ashish Kapoor; Winslow Burleson; Rosalind W. Picard
Predicting when a person might be frustrated can provide an intelligent system with important information about when to initiate interaction. For example, an automated Learning Companion or Intelligent Tutoring System might use this information to intervene, providing support to the learner who is likely to otherwise quit, while leaving engaged learners free to discover things without interruption. This paper presents the first automated method that assesses, using multiple channels of affect-related information, whether a learner is about to click on a button saying "I'm frustrated." The new method was tested on data gathered from 24 participants using an automated Learning Companion. Their indication of frustration was automatically predicted from the collected data with 79% accuracy (chance=58%). The new assessment method is based on Gaussian process classification and Bayesian inference. Its performance suggests that non-verbal channels carrying affective cues can help provide important information to a system for formulating a more intelligent response.
Keywords: Affective Learning Companion; Intelligent Tutoring System; Learner state assessment; Affect recognition
HCI reality -- an 'Unreal Tournament'? BIBAKFull-Text 737-743
  Christoph Bartneck; Matthias Rauterberg
The cooperation between designers, engineers and scientists in the human-computer interaction (HCI) community is often difficult, and can only be explained by investigating the different paradigms by which they operate. This study proposes a paradigm model for designers, engineers and scientists, using three barriers to separate the professions. We then report on an empirical study that attempted to validate the understand/transform world barrier in the paradigm model using an online questionnaire. We conclude that the used 'Attitude About Reality' scale was unsuitable for measuring this barrier, whereas information about the educational background of the participants was a good predictor for the self-reported profession (designer, engineer or scientist). Interestingly, among the three professions, engineers appear to be the cohesive element, since they often have dual backgrounds, whereas very few participants had dual science/design backgrounds. Engineers could, therefore, build a bridge between designers and scientists, and through their integrative role, could guide the HCI community to realizing its full potential.
Keywords: Human-computer interaction; Community; Paradigm; Design; Engineering; Science; Attitude About Reality
Improving password security and memorability to protect personal and organizational information BIBAKFull-Text 744-757
  Kim-Phuong L. Vu; Robert W. Proctor; Abhilasha Bhargav-Spantzel; Bik-Lam (Belin) Tai; Joshua Cook; E. Eugene Schultz
Personal information and organizational information need to be protected, which requires that only authorized users gain access to the information. The most commonly used method for authenticating users who attempt to access such information is through the use of username-password combinations. However, this is a weak method of authentication because users tend to generate passwords that are easy to remember but also easy to crack. Proactive password checking, for which passwords must satisfy certain criteria, is one method for improving the security of user-generated passwords. The present study evaluated the time and number of attempts needed to generate unique passwords satisfying different restrictions for multiple accounts, as well as the login time and accuracy for recalling those passwords. Imposing password restrictions alone did not necessarily lead to more secure passwords. However, the use of a technique for which the first letter of each word of a sentence was used coupled with a requirement to insert a special character and digit yielded more secure passwords that were more memorable.
Keywords: Authentication; Information security; Passwords

IJHCS 2007 Volume 65 Issue 9

How do people tap when walking? An empirical investigation of nomadic data entry BIBAKFull-Text 759-769
  Min Lin; Rich Goldman; Kathleen J. Price; Andrew Sears; Julie Jacko
When mobile devices are used on the move, a user's limited visual resources are split between interacting with the mobile devices and maintaining awareness of the surrounding environment. In this study, we examined stylus-based tapping operations on a PDA under three mobility situations: seated, walking on a treadmill, and walking through an obstacle course. The results revealed that Fitts' Law continues to be effective even under the most challenging obstacle course condition. While target selection times did not differ between the various mobility conditions, overall task completion times, error rates, and several measures of workload differed significantly. Diminished performance under the obstacle course condition was attributed to increased demands on attention associated with navigating through the obstacle course. Results showed that the participants in the obstacle course condition were able to tap on a 6.4 mm-diameter target with 90% accuracy, but they reduced their walking speed by 36% and perceived an increased workload. Extending earlier research, we found that treadmill-based conditions were able to generate representative data for task selection times, but accuracy differed significantly from the more realistic obstacle course condition.
Keywords: Data entry; PDA; Tapping; Walking; Fitts' Law
Deception in cyberspace: A comparison of text-only vs. avatar-supported medium BIBAKFull-Text 770-783
  Holtjona Galanxhi; Fiona Fui-Hoon Nah
The use of anthropomorphic avatars provides Internet users the opportunity and freedom to manipulate their identity. As cyberspace becomes a haven for deceptive behavior, human-computer interaction research will need to be carried out to study and understand these deceptive behaviors. The objective of this research is to investigate the behavior of deceivers and non-deceivers (or truth-tellers) in the cyberspace environment. We examine if the intention to deceive others influences one's choice of avatars in the online chat environment. We also investigate if communication medium (text-only vs. avatar-supported chat) influences one's perception of trustworthiness of the communication partner. A lab experiment was conducted in an online chat environment with dyads. The results indicate that in the text-only chat environment, subjects who were deceiving their partner experienced higher anxiety levels than those who were truthful to their partner; however, the same phenomenon was not observed in the avatar-supported chat environment. This suggests that "wearing a mask" in cyberspace may reduce anxiety in deceiving others. Additionally, deceivers are more likely to choose avatars that are different from their real selves. The results also show that the use of avatars in a computer-mediated chat environment does not have an impact on one's perceived trustworthiness.
Keywords: Avatars; Online synchronous communication; Deception; State anxiety
Usability methods' familiarity among map application developers BIBAKFull-Text 784-795
  Annu-Maaria Nivala; L. Tiina Sarjakoski; Tapani Sarjakoski
Developments in hardware and software have led to new innovative methods for visualising geospatial data. At the same time user-centred design (UCD) and usability engineering methods have a fundamental role in designing applications for new technical environments, which involve entirely new ways of interacting. However, applying methods from other research disciplines may not always be straightforward, as the product developers have to operate in a challenging interdisciplinary field. The aim of this study was to find out how usability engineering is currently included in the development of map services. Seven companies developing different types of map applications in Finland were interviewed. The results support the suitability of usability engineering for map application design, since by including the usability approach into the product design, while simultaneously taking into account the individuality and diversity of users and their tasks together with the characteristics of the maps, application developers are more likely to design products that have a higher quality of use. This study identifies the main occasions when the usability approach could be most beneficial. Furthermore, the benefits and challenges of including usability approaches in map application design are discussed. Preliminary ideas on what usability means in the context of map applications are also given. Finally, the importance for providing a basis for the further development of application-specific guidelines and techniques is addressed.
Keywords: Usability engineering; User-centred design (UCD); Usability methods; User requirements; Geographic information system (GIS); Map application; Map service; Cartography; Geovisualisation; Product design; Product development process
Determinants of success for application service provider: An empirical test in small businesses BIBAKFull-Text 796-815
  Heeseok Lee; Jeoungkun Kim; Jonguk Kim
Recently, application service provider (ASP), a new rental-based enterprise software business, has become a viable option. Although ASP has the potential to fundamentally change the manner in which IT services are provided for user firms, current ASPs often fail to show robust records in accumulating and maintaining customers. Therefore, this paper attempts to explore the main success factors for ASP-based information systems on the basis of past IS success models. Two hundred and three samples were collected from small and medium enterprises with ASP service experiences. Data analysis using LISREL shows that seven IS success factors -- system quality, information quality, service quality, intention to use, user satisfaction, individual benefit, organizational benefit and an additional factor, trust, have good fit with data gathered. These factors, except for system quality, show significant coefficients and explanatory power. Furthermore, it is found that both service quality and information quality are significant for fostering user satisfaction, trust, and intention to use.
Keywords: ASP; Application service provider/provision; IS success model; Small business
A redundancy-based method for the extraction of relation instances from the Web BIBAKFull-Text 816-831
  Viktor de Boer; Maarten van Someren; Bob J. Wielinga
The Semantic Web requires automatic ontology population methods. We developed an approach, that given existing ontologies, extracts instances of ontology relations, a specific subtask of ontology population. We use generic, domain-independent techniques to extract candidate relation instances from the Web and exploit the redundancy of information on the Web to compensate for loss of precision caused by the use of these generic methods. The candidate relation instances are then ranked based on co-occurrence with a small seed set. In an experiment, we extracted instances of the relation between artists and art styles. The results were manually evaluated against selected art resources. The method was also tested in the football domain. We also compare the performance of our ranking to that of a Google-hit count-based method.
Keywords: Semantic Web; Ontology population; Information Extraction; Web mining

IJHCS 2007 Volume 65 Issue 10

Input techniques that dynamically change their cursor activation area: A comparison of bubble and cell cursors BIBAKFull-Text 833-851
  Morten Hertzum; Kasper Hornbæk
Efficient pointing is crucial to graphical user interfaces, and input techniques that dynamically change their activation area may yield improvements over point cursors by making objects selectable at a distance. Input techniques that dynamically change their activation area include the bubble cursor, whose activation area always contains the closest object, and two variants of cell cursors, whose activation areas contain a set of objects in the vicinity of the cursor. We report two experiments that compare these techniques to a point cursor; in one experiment participants use a touchpad for operating the input techniques, in the other a mouse. In both experiments, the bubble cursor is fastest and participants make fewer errors with it. Participants also unanimously prefer this technique. For small targets, the cell cursors are generally more accurate than the point cursor; in the second experiment the box cursor is also faster. The cell cursors succeed in letting participants select objects while the cursor is far away from the target, but are relatively slow in the final phase of target acquisition. We discuss limitations and possible enhancements of input techniques with activation areas that contain multiple objects.
Keywords: Input techniques; Interaction techniques; Cell cursors; Touchpad; Bubble cursor; Box cursor; Pie cursor
Incorporating tutoring principles into interactive knowledge acquisition BIBAKFull-Text 852-872
  Jihie Kim; Yolanda Gil
This paper argues that interactive knowledge acquisition systems would benefit from a tighter and more thorough incorporation of tutoring and learning principles. Current acquisition systems learn from users in a passive manner, and could instead be designed to incorporate the proactive capabilities that one expects of a good student. We first describe our analysis of the literature on teacher-student interaction and present a compilation of tutoring and learning principles that are relevant to interactive knowledge acquisition systems. We then point out what tutoring and learning principles have been used to date in the acquisition literature, though unintentionally and implicitly, and discuss how a more thorough and explicit representation of these principles would help improve how computers learn from users. We present our design and an initial implementation of an acquisition dialogue system called SLICK that represents acquisition principles and goals explicitly and declaratively, making the system actively reason about various acquisition tasks and generate its interactions dynamically. Finally, we discuss promising directions in designing acquisition systems by structuring interactions with users according to tutoring and learning principles.
Keywords: Interactive knowledge acquisition; Procedural knowledge
Using bat-modelled sonar as a navigational tool in virtual environments BIBAKFull-Text 873-886
  Dean A. Waters; Husam H. Abulula
Bats are able to use active sonar as a mechanism for locating object in three dimensions and for generating spatial maps of their environments. Humans use passive sound cues to detect features of the space they occupy, as well as react to the spatial location of objects which generate sound. The system described in this paper allows free-ranging humans to locate a virtual sound location using active sonar. An emitted pulse, centred on the users head, serves as an intensity and time marker. The return pulse is rendered at the virtual target location and emitted after a time delay corresponding to the two-way path from sender to target and back again. The sonar system is modelled on those of bats, using ultrasonic frequency-modulated signals reflected from simple targets. The model uses the reflectivity characteristics of ultrasound, but the frequency and temporal structure used are scaled, with the speed of sound being set to 8.5 ms-1 to bring the frequency range and temporal resolution within the capabilities of the human auditory system. Orientation with respect to the ensonified target is achieved by time-of-flight time delays to give target range, and binaural location information derived from interaural timing differences, interaural intensity differences, and head-related transfer functions. Subjects performed significantly better at a localization task when given temporal data based on echo delays with an outgoing reference pulse than without a reference pulse. Frequency-modulated signals sweeping from 1.5 kHz-100 Hz over 500 ms provide the best localization cues, and users found them significantly easier to locate than continuous sounds.
Keywords: Bat; Virtual reality; Echolocation; Sonar; Virtual acoustics
Using a cognitive model to generate web navigation support BIBAKFull-Text 887-897
  Herre van Oostendorp; Ion Juvina
A computational cognitive model of web navigation is proposed. Based on theories and models of text comprehension and web navigation, the plausibility of the proposed model is discussed. The model was used to generate navigation support and this support was offered to users in real time during their navigation sessions, in two experiments. In the first experiment navigation support was offered in the auditory modality and it had a positive effect on user's task performance, especially for users with low spatial abilities. In the second experiment navigation support was offered in the visual modality and users positively evaluated it. Users navigated in a more structured way, judged the system as more usable, and perceived themselves as less disoriented. Support did also here lead to better task performance. Finally, some aspects concerning further enhancement of the validity of the proposed model and its practical relevance are discussed.
Keywords: Cognitive modelling; Individual differences; Web navigation; Navigation support; Information scent

IJHCS 2007 Volume 65 Issue 11

An interactional perspective on group awareness: Alleviating the information-exchange dilemma (for everybody?) BIBAKFull-Text 899-910
  Joachim Kimmerle; Ulrike Cress; Friedrich W. Hesse
In situations of computer-mediated communication and computer-supported cooperation, a central challenge lies in increasing the willingness of those involved to share their information with the other group members. In the experimental work presented here, a shared-database setting is selected as a prototypical situation of net-based information exchange and examined from a social-dilemma perspective: the individual who contributes information to a shared database must reckon with costs and no benefits. The most efficient strategy from the perspective of the individual is thus to withhold information. Previous research has shown that a group-awareness tool which provides information about the contribution behavior of group members influences people's information-exchange behavior. In order to examine the psychological processes underlying these effects of group awareness in more detail, the present study adopts an interactional approach, according to which person-situation interaction is investigated. Certain personality traits (interpersonal trust, sensation seeking, and self-monitoring) were measured and several hypotheses tested regarding the reactions of individuals with high and low trait values to different types of awareness information. Results demonstrate that awareness tools providing information about highly cooperative group members encourage participants to trust one another and minimize the risk of being exploited. When an awareness tool additionally provides feedback about the contribution behavior of single individuals, it becomes an opportunity for self-presentation. In conclusion, an interactional approach which considers personality traits and situational factors in a net-based information-exchange situation provides new insights into both the influence processes of group awareness and the connection of these processes to specific personality traits with respect to contribution behavior.
Keywords: Information exchange; Group awareness; Personality traits; Interpersonal trust; Risk taking; Self-presentation
Top-down and bottom-up influences on learning from animations BIBAKFull-Text 911-930
  Sarah Kriz; Mary Hegarty
To evaluate how top-down and bottom-up processes contribute to learning from animated displays, we conducted four experiments that varied either in the design of animations or the prior knowledge of the learners. Experiments 1-3 examined whether adding interactivity and signaling to an animation benefits learners in developing a mental model of a mechanical system. Although learners utilized interactive controls and signaling devices, their comprehension of the system was no better than that of learners who saw animations without these design features. Furthermore, the majority of participants developed a mental model of the system that was incorrect and inconsistent with information displayed in the animation. Experiment 4 tested effects of domain knowledge and found, surprisingly, that even some learners with high domain knowledge initially constructed the incorrect mental model. After multiple exposures to the materials, the high knowledge learners revised their mental models to the correct one, while the low-knowledge learners maintained their erroneous models. These results suggest that learning from animations involves a complex interplay between top-down and bottom-up processes and that more emphasis should be placed on how prior knowledge is applied to interpreting animations.
Keywords: Animations; Mental Models; Interactivity; Learning
An empirical evaluation of four data visualization techniques for displaying short news text similarities BIBAKFull-Text 931-944
  Marcus A. Butavicius; Michael D. Lee
An experiment was conducted comparing user performance on four data visualization techniques -- an unstructured display condition consisting of a random one-dimensional (1D) list and three proximity-based representations including a 1D list ranked by a greedy nearest-neighbor algorithm and two 2D spatial visualizations using the ISOMAP layout algorithm and multidimensional scaling (MDS). Eighty-one participants completed an information retrieval task where the visualization techniques were used to display a corpus consisting of 50 short news texts. Human pairwise similarity judgments for this corpus were used to create the three proximity-based displays. Results demonstrated an advantage in accuracy, the number of documents accessed, and, to a lesser extent, subjective confidence in these displays over the Random List condition and in the 2D over the 1D displays. Similar, but smaller, advantages were observed in the MDS display over ISOMAP however none of these pairwise comparisons were statistically significant. A sequential analysis of participant actions in terms of the proximity of document representations accessed provided some explanation for variations in performance between the displays as well as indicating strategic differences in interactions particularly between visualizations of different dimensionality.
Keywords: Data visualization; Multidimensional scaling; ISOMAP; Empirical evaluation; Human-computer interaction
Navigation in 3D virtual environments: Effects of user experience and location-pointing navigation aids BIBAKFull-Text 945-958
  Stefano Burigat; Luca Chittaro
In this paper, we describe the results of an experimental study whose objective was twofold: (1) comparing three navigation aids that help users perform wayfinding tasks in desktop virtual environments (VEs) by pointing out the location of objects or places; (2) evaluating the effects of user experience with 3D desktop VEs on their effectiveness with the considered navigation aids. In particular, we compared navigation performance (in terms of total time to complete an informed search task) of 48 users divided into two groups: subjects in one group had experience in navigating 3D VEs while subjects in the other group did not. The experiment comprised four conditions that differed for the navigation aid that was employed. The first and the second condition, respectively, exploited 3D and 2D arrows to point towards objects that users had to reach; in the third condition, a radar metaphor was employed to show the location of objects in the VE; the fourth condition was a control condition with no location-pointing navigation aid available. The search task was performed both in a VE representing an outdoor geographic area and in an abstract VE that did not resemble any familiar environment. For each VE, users were also asked to order the four conditions according to their preference. Results show that the navigation aid based on 3D arrows outperformed (both in terms of user performance and user preference) the others, except in the case when it was used by experienced users in the geographic VE. In that case, it was as effective as the others. Finally, in the geographic VE, experienced users took significantly less time than inexperienced users to perform the informed search, while in the abstract VE the difference was significant only in the control and the radar conditions. From a more general perspective, our study highlights the need to take into specific consideration user experience in navigating VEs when designing navigation aids and evaluating their effectiveness.
Keywords: Virtual environments; Navigation aids; Evaluation

IJHCS 2007 Volume 65 Issue 12

Worlds and transformations: Supporting the sharing and reuse of engineering design knowledge BIBAKFull-Text 959-982
  Zdenek Zdrahal; Paul Mulholland; Michael Valasek; Ansgar Bernardi
Design involves the formulation of a solution, such as a product specification, from initial requirements. Design in industrial and other contexts often involves the building and use of models that allow the designer to test hypotheses and learn from possible design decisions prior to building the physical product. The building and testing of models is a design process in its own right.
   Previous work in knowledge management, design rationale and the psychology of design has demonstrated that designers often vary from prescriptive methodologies of the design process and have problems appropriately describing their design activity in order to support design collaboration and the reuse of design artefacts. Drawing on this work, we support design collaboration and reuse structured according to key transformational episodes in the design process and the design artefacts they produce. To support this, we characterise the design task as progressing through a series of worlds, each comprising its own concepts and vocabulary, and supported by its own design tools. The design process can then be described in terms of important transformations that are made from one world to the next. This allows a targeted approach to rationale capture integrated with work practice and associated with products of the design process.
   This approach has been successfully deployed and tested in two industrial engineering companies. Findings included improved collaboration in design teams, effective reuse and improved training for new members of the design team. This work has more general implications for the development of design rationale methods and tools to support the design process.
Keywords: Design; Collaboration; Design reuse; Design rationale; Knowledge management
Effect of modality on collaboration with a dialogue system BIBAKFull-Text 983-991
  Ludovic Le Bigot; Patrice Terrier; Virginie Amiel; Gérard Poulain; Eric Jamet; Jean-François Rouet
The aim of this study was to investigate the influence of modality on collaboration processes between human and computer. Spoken and written interactions with a natural language dialogue system were compared using two real information-retrieval systems. In order to look for a restaurant (Experiment 1) or plan a trip (Experiment 2), participants performed several task-oriented dialogue scenarios. Although the spoken interaction mode was less efficient, it promoted collaboration, the use of personal pronouns and the literal form of the system's command utterances. Overall, in the written mode, the emphasis was on the task and its performance, rather than on dialogue. These findings are discussed with respect to the effect of communication mode on collaboration in human-computer dialogue.
Keywords: Collaboration; Human-computer dialogue; Grounding; Modality
Debugging strategies and tactics in a multi-representation software environment BIBAKFull-Text 992-1009
  Pablo Romero; Benedict du Boulay; Richard Cox; Rudi Lutz; Sallyann Bryant
Abstract This paper investigates the interplay between high level debugging strategies and low level tactics in the context of a multi-representation software development environment (SDE). It investigates three questions. 1. How do programmers integrate debugging strategies and tactics when working with SDEs? 2. What is the relationship between verbal ability, level of graphical literacy and debugging (task) performance. 3. How do modality and perspective influence debugging strategy and deployment of tactics? The paper extends the work of Katz and Anderson [1988. Debugging: an analysis of bug location strategies. Human-Computer Interaction 3, 359-399] and others in terms of identifying high level debugging strategies, in this case when working with SDEs. It also describes how programmers of different backgrounds and degrees of experience make differential use of the multiple sources of information typically available in a software debugging environment. Individual difference measures considered among the participants were their programming experience and their knowledge of external representation formalisms. The debugging environment enabled the participants, computer science students, to view the execution of a program in steps and provided them with concurrently displayed, adjacent, multiple and linked programming representations. These representations comprised the program code, two visualisations of the program and its output. The two visualisations of the program were available, in either a largely textual format or a largely graphical format so as to track interactions between experience and low level mode-specific tactics, for example.
   The results suggest that (i) additionally to deploying debugging strategies similar to those reported in the literature, participants also employed a strategy specific to SDEs, following execution, (ii) verbal ability was not correlated with debugging performance, (iii) knowledge of external representation formalisms was as important as programming experience to succeed in the debugging task, and (iv) participants with greater experience of both programming and external representation formalisms, unlike the less experienced, were able to modify their debugging strategies and tactics effectively when working under different format conditions (i.e. when working with either largely graphical or largely textual visualisations) in order to maintain their high debugging accuracy level.
Keywords: Multiple external representations; Graphical reasoning; Program debugging