HCI Bibliography Home | HCI Journals | About IJHCS | Journal Info | IJHCS Journal Volumes | Detailed Records | RefWorks | EndNote | Hide Abstracts
IJHCS Tables of Contents: 525354555657585960616263646566676869707172

International Journal of Human-Computer Studies 62

Editors:Enrico Motta; Susan Wiedenbeck
Dates:2005
Volume:62
Publisher:Elsevier Science Publishers
Standard No:ISSN 0020-7373; TA 167 A1 I5
Papers:36
Links:Table of Contents
  1. IJHCS 2005 Volume 62 Issue 1
  2. IJHCS 2005 Volume 62 Issue 2
  3. IJHCS 2005 Volume 62 Issue 3
  4. IJHCS 2005 Volume 62 Issue 4
  5. IJHCS 2005 Volume 62 Issue 5
  6. IJHCS 2005 Volume 62 Issue 6

IJHCS 2005 Volume 62 Issue 1

ARTICLE

The rising pitch metaphor: an empirical study BIBAKFull-Text 1-20
  Dimitrios Rigas; James Alty
This paper describes a set of experiments that investigated the use of rising pitch notes to communicate graphical information to visually impaired users. The information communicated in the experiments included coordinate locations within a 40x40 graphical grid, the navigation of an auditory cursor within the graphical grid, the communication of simple graphical shapes and their size. The five simple shapes communicated were rectangles, squares, circles, horizontal and vertical lines. Stereophony, timbre, rhythms, and short tunes were used in addition to the rising pitch metaphor to aid disambiguation. Results suggested that the rising pitch approach enabled visually impaired users to understand the graphical information communicated in the absence of any visual aid. The paper concludes with a discussion of the use of rising pitch metaphor to communicate graphical information.
Keywords: Auditory User Interface; Graphics; Visually impaired users; Earcons
Exploring the use of structured musical stimuli to communicate simple diagrams: the role of context BIBAKFull-Text 21-40
  James L. Alty; Dimitrios Rigas
The results from previous experiments using structured musical stimuli to communicate coordinate locations within a graphical grid, navigation of an auditory cursor and simple shapes are used as a basis for further exploratory research to communicate diagrams. An experimental framework program (called AudioGraph) provided a platform for investigating musical information processing for blind users. Under this platform, simple arrangements of shapes (forming diagrams) were communicated to users using structured musical stimuli. Meaningfully arranged graphical shapes (at least for the visual sense) were communicated in the absence, and in the presence of a particular perceptual context or different perceptual contexts. The results indicated that perceptual context played an important role in the interpretation of the structured musical stimuli that communicated simple diagrams. The paper concludes with a discussion on the implications of the results, the role of context and the use of structured musical stimuli to communicate graphical information to visually impaired users.
Keywords: User interfaces; Earcons; Structured musical stimuli; Communication metaphors; Graphics; Music; Auditory channel
System-initiated digressive proposals in automated human-computer telephone dialogues: the use of contrasting politeness strategies BIBAKFull-Text 41-71
  J. Wilkie; M. A. Jack; P. J. Littlewood
System-initiated digressive proposals may be used to introduce new and unexpected information into automated telephone services. These digressions may be viewed as particularly pronounced forms of unsolicited interruptions as they contain information not directly related to the caller's intended activity. In human-human conversation, interruptions are considered to be speech acts which intrinsically threaten both the positive and negative face wants of the addressee and conversants adopt specific verbal strategies to mitigate the negative impact of their interruptions. A question therefore arises whether the introduction of face-redressive expressions, based on human-human conversational strategies, into the design of system-initiated proposals in automated services can mitigate the negative impact of the interruptions. A usability experiment was conducted to examine the effectiveness of three contrasting politeness strategies for system-initiated digressions in a mass-market telephone banking dialogue using speech recognition technology. Participants (N=111) experienced these proposals while using the automated service to perform banking tasks. Results indicated that all these system-initiated digressions -- irrespective of politeness strategy employed -- had a negative impact on the user attitudes towards the service. This paper reports these results and explores participants' perceptions of the politeness styles and registers employed in the system-initiated proposals.
Keywords: Politeness theory; Natural language interface; Dialogue design; Dialogue evaluation; Usability; Automated telephone banking; System-initiated digression; Interruption
Efficient comparison of platform alternatives in interactive virtual reality applications BIBAKFull-Text 73-103
  Pablo Figueroa; Walter F. Bischof; Pierre Boulanger; H. James Hoover
Virtual reality applications consist of an integrated combination of elements, such as hardware devices, interaction techniques, and content, in different modalities and qualities. Designers of virtual reality applications select combinations of such elements that allow users to accomplish their tasks, and it is feasible that more than one combination of such values will satisfy the user's needs. Unfortunately, current development environments, methodologies, and techniques in the field of virtual reality often preclude the exploration of the design alternatives, due to coverage or cost limitations. A limited number of options are covered by any given software development environment, and the development cost of new prototypes in such development platforms is too high to be considered as an evaluation tool. In this paper, we present a methodology for partial (i.e. hardware and interaction techniques alternatives) exploration of the design space of a virtual reality application, based on the creation of reusable components and a standard evaluation of alternatives. Since the cost of developing several versions of an application can be reduced by reusing elements from others, this method allows designers to evaluate the performance and user preferences of several implementations. As a proof of concept, we developed four versions of a simple matching application in different virtual reality platforms. Results of this study show how users react to each prototype and how the different solutions can be compared, no matter how different in technology they are.
Keywords: Virtual reality; Iterative development; User studies in virtual reality; Interaction techniques markup language; InTml
Interface changes causing accidents. An empirical study of negative transfer BIBAKFull-Text 105-125
  Denis Besnard; Lucile Cacitti
When expert operators interact with a new device, they inevitably reuse former interaction modes and actions. This phenomenon is due to the human cognition seeking resources savings. Schemas support this strategy and are implemented in such a way that perfection is disregarded at the profit of an intuitive trade-off between performance and cognitive resources savings. As a consequence, humans have a strong inclination to fit well-known solution procedures into new problems. For this reason, changes in work environments can cause accidents when they allow operators to interact with a new device if the latter is erroneously perceived as familiar. This research issue originates from an industrial background. The suspected cause of a fatal error performed by an operator in a steelworks factory is replicated in an experiment. The results support the hypothesis according to which errors (and possible subsequent accidents) due to changes in the interface are more likely when the latter does not inhibit former modes of interaction modes. This main result is discussed under the angle of cognitive ergonomics and used as a basis to provide design guidelines.
Keywords: Negative transfer; Accident; Interface changes; Human-machine interaction; Human error
Evaluating event visualization: a usability study of COPLINK spatio-temporal visualizer BIBAKFull-Text 127-157
  Wingyan Chung; Hsinchun Chen; Luis G. Chaboya; Christopher D. O'Toole; Homa Atabakhsh
Event visualization holds the promise of alleviating information overload in human analysis and numerous tools and techniques have been developed and evaluated. However, previous work does not specifically address either the coordination of event dimensions with the types of tasks involved or the way that visualizing different event dimensions can benefit human analysis. In this paper, we propose a taxonomy of event visualization and present a methodology for evaluating a coordinated event visualization tool called COPLINK Spatio-Temporal Visualizer (STV). The taxonomy encompasses various event dimensions, application domains, visualization metaphors, evaluation methods and performance measures. The evaluation methodology examines different event dimensions and different task types, thus juxtaposing two important elements of evaluating a tool. To achieve both internal and external validity, a laboratory experiment with students and a field study with crime analysis experts were conducted. Findings of our usability study show that STV could support crime analysis involving multiple, coordinated event dimensions as effectively as it could analyze individual, uncoordinated event dimensions. STV was significantly more effective and efficient than Microsoft Excel in performing coordinated tasks and was significantly more efficient in doing uncoordinated tasks related to temporal, spatial and aggregated information. Also, STV had compared favorably with Excel in completing uncoordinated tasks related to temporal and spatial information, respectively. Subjects' comments showed STV to be intuitive, useful and preferable to existing crime analysis methods.
Keywords: Event visualization; Information visualization; Usability; Evaluation methodology; Taxonomy; COPLINK; Spatio-Temporal Visualizer; Crime analysis; Intelligence analysis; National security; Law enforcement

IJHCS 2005 Volume 62 Issue 2

EDITORIAL

Special issue on subtle expressivity for characters and robots BIBFull-Text 159-160
  Noriko Suzuki; Christoph Bartneck

ARTICLE

Computers that care: investigating the effects of orientation of emotion exhibited by an embodied computer agent BIBAKFull-Text 161-178
  Scott Brave; Clifford Nass; Kevin Hutchinson
Embodied computer agents are becoming an increasingly popular human-computer interaction technique. Often, these agents are programmed with the capacity for emotional expression. This paper investigates the psychological effects of emotion in agents upon users. In particular, two types of emotion were evaluated: self-oriented emotion and other-oriented, empathic emotion. In a 2 (self-oriented emotion: absent vs. present) by 2 (empathic emotion: absent vs. present) by 2 (gender dyad: male vs. female) between-subjects experiment (N=96), empathic emotion was found to lead to more positive ratings of the agent by users, including greater likeability and trustworthiness, as well as greater perceived caring and felt support. No such effect was found for the presence of self-oriented emotion. Implications for the design of embodied computer agents are discussed and directions for future research suggested.
Keywords: Embodied agents; Affective computing; Emotion; Empathy; Characters; Social interfaces; Empirical studies
Subtle emotional expressions of synthetic characters BIBAFull-Text 179-192
  Christoph Bartneck; Juliane Reichenbach
This study examines the influence of the geometrical intensity of an emotional facial expression on the perceived intensity and the recognition accuracy. The stimuli consisted of synthetic faces at ten geometrical intensity levels in each of the five emotional categories. A curve-linear relationship was found between geometrical and perceived intensity. Steps of 20% geometrical intensity appear to be appropriate to enable the participants to distinguish the intensity levels. At about 30% geometrical intensity the recognition accuracy reached a level that was not significantly different from each emotions maximum recognition accuracy. This point indicates a categorical perception of the facial expressions. The results of this study are of particular importance for the developers of synthetic characters and might help them to create more subtle characters.
TelMeA -- Expressive avatars in asynchronous communications BIBAFull-Text 193-209
  Toru Takahashi; Christoph Bartneck; Yasuhiro Katagiri; Noriko H. Arai
TelMeA is an asynchronous online community system that uses avatars to enact the messages of the users. We present an overview of the system, including the results of a usability study and its effect on the redesign of the system. Furthermore we present an empirical evaluation of the avatar's animations. The animations offer a wide repertoire of expressions along the valence dimension, but additional animations with low arousal should be added. Next we performed a case study of TelMeA in Japan. The members of the community more often used the high arousal and extreme valence animations, but the more subtle animations were still used in 30% of all cases. The less frequent use of subtle expressions could be explained by the fact they are not necessary in an asynchronous communication to negotiate turn taking.
Variations in gesturing and speech by GESTYLE BIBAKFull-Text 211-229
  Han Noot; Zsofia Ruttkay
Humans tend to attribute human qualities to computers. It is expected that people, when using their natural communicational skills, can perform cognitive tasks with computers in a more enjoyable and effective way. For these reasons, human-like embodied conversational agents (ECAs) as components of user interfaces have received a lot of attention. It has been shown that the style of the agent's look and behaviour strongly influences the user's attitude. In this paper we discuss our GESTYLE language making it possible to endow ECAs with style. Style is defined in terms of when and how the ECA uses certain gestures, and how it modulates its speech (e.g. to indicate emphasis or sadness). There are also GESTYLE tags to annotate text, which has to be uttered by an ECA to prescribe the usage of hand, head and facial gestures accompanying the speech in order to augment the communication. The annotation ranges from direct, low level (e.g. perform a specific gesture) to indirect, high level (e.g. take turn in a conversation) instructions, which will be interpreted with respect to the style defined. Using style dictionaries and defining different aspects like age and culture of an ECA, it is possible to tune the behaviour of an ECA to suit a given user or target group the best.
Keywords: Embodied conversational agent; Multimodal communication; Style; Mark up language
Using human physiology to evaluate subtle expressivity of a virtual quizmaster in a mathematical game BIBAKFull-Text 231-245
  Helmut Prendinger; Junichiro Mori; Mitsuru Ishizuka
The aim of the experimental study described in this article is to investigate the effect of a life-like character with subtle expressivity on the affective state of users. The character acts as a quizmaster in the context of a mathematical game. This application was chosen as a simple, and for the sake of the experiment, highly controllable, instance of human-computer interfaces and software. Subtle expressivity refers to the character's affective response to the user's performance by emulating multimodal human-human communicative behavior such as different body gestures and varying linguistic style. The impact of em-pathic behavior, which is a special form of affective response, is examined by deliberately frustrating the user during the game progress. There are two novel aspects in this investigation. First, we employ an animated interface agent to address the affective state of users rather than a text-based interface, which has been used in related research. Second, while previous empirical studies rely on questionnaires to evaluate the effect of life-like characters, we utilize physiological information of users (in addition to questionnaire data) in order to precisely associate the occurrence of interface events with users' autonomic nervous system activity. The results of our study indicate that empathic character response can significantly decrease user stress and that affective behavior may have a positive effect on users' perception of the difficulty of a task.
Keywords: Life-like characters; Affective behavior; Empathy; Physiological user information; Evaluation
Cooperative embodied communication emerged by interactive humanoid robots BIBAKFull-Text 247-265
  Daisuke Sakamoto; Takayuki Kanda; Tetsuo Ono; Masayuki Kamashima; Michita Imai; Hiroshi Ishiguro
Research on humanoid robots has produced various uses for their body properties in communication. In particular, mutual relationships of body movements between a robot and a human are considered to be important for smooth and natural communication, as they are in human-human communication. We have developed a semi-autonomous humanoid robot system that is capable of cooperative body movements with humans using environment-based sensors and switching communicative units. Concretely, this system realizes natural communication by using typical behaviors such as: "nodding," "eye-contact," "face-to-face," etc. It is important to note that the robot parts are NOT operated directly; only the communicative units in the robot system are switched. We conducted an experiment using the mentioned robot system and verified the importance of cooperative behaviors in a route-guidance situation where a human gives directions to the robot. The task requires a human participant (called the "speaker") to teach a route to a "hearer" that is (1) a human, (2) a developed robot that performs cooperative movements, and (3) a robot that does not move at all. This experiment is subjectively evaluated through a questionnaire and an analysis of body movements using three-dimensional data from a motion capture system. The results indicate that the cooperative body movements greatly enhance the emotional impressions of human speakers in a route-guidance situation. We believe these results will allow us to develop interactive humanoid robots that sociably communicate with humans.
Keywords: Human-robot interaction; Entrainment; Subjective experiments; Environment-based sensing
Differences in effect of robot and screen agent recommendations on human decision-making BIBAKFull-Text 267-279
  Kazuhiko Shinozawa; Futoshi Naya; Junji Yamato; Kiyoshi Kogure
This paper compares the effect of a robot's and on-screen agent's recommendations on human decision-making using a quantitative evaluation method. We are interested in whether a robot's physical body produces some differences in the effect or not. Previous research investigated the advantage of a physical body; however, the advantage was not clarified quantitatively and there was not enough evidence to give the results credibility. Our method based on quantitative evaluation clarifies the effect of a robot's and on-screen agent's behavior on user decision-making. Comparing a robot's behavior with an on-screen agent's, we show that the degree of the effect firmly depends on the interaction environment and that geometrical consistency between the interaction environment and embodied social agents (ESAs), which include robots and on-screen agents, is important in the recommendation situation.
Keywords: Human-robot interaction; Interactive social agents; Social responses to technology; Persuasion
Manipulation of non-verbal interaction style and demographic embodiment to increase anthropomorphic computer character credibility BIBAKFull-Text 281-306
  Andrew J. Cowell; Kay M. Stanney
For years, people have sought more natural means of communicating with their computers. Many have suggested that interaction with a computer should be as easy as interacting with other people, taking advantage of the multimodal nature of human communication. While users should, in theory, gravitate to such anthropomorphic embodiments, quite the contrary has been experienced; users generally have been dissatisfied and abandoned their use. This suggests a disconnect between factors that make human-human communication engaging and those used by designers to support human-agent interaction. This paper discusses a set of empirical studies that attempted to replicate human-human non-verbal behavior. The focus revolved around behaviors that portray a credible facade, thereby helping embodied conversational agents (ECAs) to form a successful cooperative dyad with users. Based on a review of the non-verbal literature, a framework was created that identified trustworthy and credible non-verbal behaviors across five areas and formed design guidelines for character interaction. The design suggestions for those areas emanating from the facial region were experimentally supported but there was no concordant increase in perceived trust when bodily regions (posture, gesture) were added. In addition, in examining the importance of demographic elements in embodiment, it was found that users prefer to interact with characters that match their ethnicity and are young looking. There was no significant preference for gender. The implications of these results, as well as other interesting consequences are discussed.
Keywords: Anthropomorphic interfaces; Interface agents; Non-verbal behavior

IJHCS 2005 Volume 62 Issue 3

ARTICLE

Presence, memory and interaction in virtual environments BIBAKFull-Text 307-327
  Alistair Sutcliffe; Brian Gault; Jae-Eun Shin
An experimental study is described, comparing presence, memory, and interaction in three different virtual environments: CAVE, Interactive WorkBench, and Reality Room. The aim of the experiment was to investigate possible relationships between these three parameters. It was found that the CAVE was remembered better, had better usability, and provided a better sense of presence to its users.
Keywords: Virtual environment; CAVE; Interactive workbench; Reality room; Presence; Memory; Heuristics, manipulation tasks
The emergence of the contextual role of the e-book in cognitive processes through an ecological and functional analysis BIBAKFull-Text 329-348
  Thierry Morineau; Caroline Blanche; Laurence Tobin; Nicolas Gueguen
An electronic book is a new means of presenting text, allowing downloading of documents and multiple readings on a portable computer. On the basis of an ecological and functional analysis of paper and electronic books with the Abstraction Hierarchy method, we tested the ability of a mobile e-book device to be an external memory trigger, assisting the recall of information content through its presence as a contextual index. In contrast to the classical experimental approach for research on reading and comprehension, we consider screen and paper as relevant cognitive tools per se. Specifically, we compare a book on a pocket computer and a paper book. Hypothesising that the physical reading support could serve as a contextual cue for memory, we experimented with groups of participants who could or could not see the support during recall. We measured the reading time, and the material later recalled was classified according to its cognitive nature. After recall, participants had to assess the sensory-motor properties of the reading support with the Osgood semantic differential and to note the humour level of the text. Results show that the e-book presence hinders recall of assimilated information whilst the presence of the paper support tends to facilitate it. Finally, we observed some correlation between sensory-motor assessment of the support and certain aspects of text cognitive processing: humour scoring, reading time and recall performance. These results lead us to conclude there is a critical relation between the sensory-motor experience of the support and the cognitive processing of the text content. This relationship might explain the positive or negative contextual effect of the support on recall performance.
Keywords: Contextual cue; Episodic memory; E-book; Ecological psychology; Abstraction hierarchy; Sensory-motor evaluation
The effects of task complexity and time availability limitations on human performance in database query tasks BIBAKFull-Text 349-379
  Heikki Topi; Joseph S. Valacich; Jeffrey A. Hoffer
Prior research on human ability to write database queries has concentrated on the characteristics of query interfaces and the complexity of the query tasks. This paper reports the results of a laboratory experiment that investigated the relationship between task complexity and time availability, a characteristic of the task context not investigated in earlier database research, while controlling the query interface, data model, technology, and training. Contrary to expectations, when performance measures were adjusted by the time used to perform the task, time availability did not have any effects on task performance while task complexity had a strong influence on performance at all time availability levels. Finally, task complexity was found to be the main determinant of user confidence. The implications of these results for future research and practice are discussed.
Keywords: Usability; Database query task; Task complexity; Time availability; Time pressure
The mechanics of trust: A framework for research and design BIBAKFull-Text 381-422
  Jens Riegelsberger; M. Angela Sasse; John D. McCarthy
With an increasing number of technologies supporting transactions over distance and replacing traditional forms of interaction, designing for trust in mediated interactions has become a key concern for researchers in human computer interaction (HCI). While much of this research focuses on increasing users' trust, we present a framework that shifts the perspective towards factors that support trustworthy behavior. In a second step, we analyze how the presence of these factors can be signalled. We argue that it is essential to take a systemic perspective for enabling well-placed trust and trustworthy behavior in the long term. For our analysis we draw on relevant research from sociology, economics, and psychology, as well as HCI. We identify contextual properties (motivation based on temporal, social, and institutional embeddedness) and the actor's intrinsic properties (ability, and motivation based on internalized norms and benevolence) that form the basis of trustworthy behavior. Our analysis provides a frame of reference for the design of studies on trust in technology-mediated interactions, as well as a guide for identifying trust requirements in design processes. We demonstrate the application of the framework in three scenarios: call centre interactions, B2C e-commerce, and voice-enabled on-line gaming.
Keywords: Trust; Social capital; Dis-embedding; Interpersonal cues; Human computer interaction; Computer mediated communication; Computer supported collaborative work; Decision-making; Game theory; E-commerce

ERRATUM

Erratum to: "The production and recognition of emotions in speech: features and algorithms": [Int. J. Hum.-Comput. Stud. 59 (2003) 157] BIBFull-Text 423
  Pierre-Yves Oudeyer

IJHCS 2005 Volume 62 Issue 4

ARTICLE

Time-related behaviour in multitasking situations BIBAKFull-Text 425-455
  Yan Zhang; Ravindra S. Goonetilleke; Thomas Plocher; Sheau-Farn Max Liang
Researchers have classified differing time-related behaviours as Monochronicity (M) and Polychronicity (P). The objective of this study was to evaluate control strategy and control performance differences between M and P persons in a process control domain. Forty-two people participated in an experimental study. Time-related behaviour was evaluated using the Modified Polychronic Attitude Index 3 (M/P score) scale. Each participant was asked to monitor and control two processes at the same time using the Control Station software. A 2 (control system order)*5 (trials) factorial experiment was used. Performance was quantified using overall mean error and overall Root-Mean-Square (RMS) error. Control strategy was quantified using the number of switches between the two processes and the number of magnitude changes within each of the processes. Correlation and regression analyses showed that the M/P score was significantly correlated with the strategy variables and performance variables. When the participants were split into the three groups, M (M/P score greater than or equal to 1 and less than or equal to 3), neutral (M/P score between 3 and 5) and P (M/P score greater than or equal to 5 and less than or equal to 7), there were significant differences in the performance and strategy measures among the three groups. The strategy variables indicated that monochrons attempted to control the two processes serially, while polychrons controlled both processes somewhat simultaneously. The neutral group was in-between the M and P groups. The results also showed that the overall mean error and overall RMS error of polychrons were significantly smaller than that of the monochrons. Furthermore, there was no significant difference in the NASA-Task Load Index score between monochrons and polychrons, even though there were significant correlations between the M/P score and some of the scale dimensions' weightings. The results of this study can have important implications for the training and selection of personnel in multitask situations, such as industrial process control.
Keywords: Monochronicity; Polychronicity; Multitasking; Process control
Supporting the cognitive process of user interface design with reusable design cases BIBAKFull-Text 457-486
  Huhn Kim; Wan Chul Yoon
User interface (UI) design is one of the most challenging problem-solving activities that the modern industry faces. The cognitive complexity of design problems and the time pressure due to shortened product life cycles force designers to pursue efficient processes and strategies. For efficiency, UI designers can benefit from their prior design experience that associates target user tasks with available interface means. The practical design activity thus tends to be case-based rather than analytic and linearly deductive. In this paper we develop a framework for a case-based design aid that enables effective reuse of prior design cases in a way that is compatible with practical strategies of designers. In the centre of the framework lies design-case representation at multiple levels of abstraction. The multi-level representation supports the bi-directional and opportunistic strategies of UI designers by enabling easy retrieval of cases at a focused abstraction level and strategy-compatible navigation to related design cases at other levels. A diagrammatic interaction model and a retrieval algorithm based on the model to represent and select design cases are described. It is experimentally verified that the multi-level representation of design cases with the diagrammatic model is useful to UI designers. The overall framework is implemented in a prototype system and the usefulness of the system is shown by examples.
Keywords: Interaction design; Designer strategy; Design aid; Case-based aiding
An empirical comparison of use-in-motion evaluation scenarios for mobile computing devices BIBAKFull-Text 487-520
  Leon Barnard; Ji Soo Yi; Julie A. Jacko; Andrew Sears
There is a clear need for evaluation methods that are specifically suited to mobile device evaluation, largely due to the vast differences between traditional desktop computing and mobile computing. One difference of particular interest that needs to be accounted for is that mobile computing devices are frequently used while the user is in motion, in contrast to desktop computing. This study aims to validate the appropriateness of two evaluation methods that vary in representativeness of mobility, one that uses a treadmill to simulate motion and another that uses a controlled walking scenario. The results lead to preliminary guidelines based on study objectives for researchers wishing to use more appropriate evaluation methodologies for empirical, data-driven mobile computing studies. The guidelines indicate that using a treadmill for mobile evaluation can yield representative performance measures, whereas a controlled walking scenario is more likely to adequately simulate the actual user experience.
Keywords: Context; Context-aware; Mobile computing; Mobility; Evaluation; Empirical
On the passage of time: Temporal differences in video-mediated and face-to-face interaction BIBAKFull-Text 521-542
  Rick van der Kleij; Roos Paashuis; Jan Maarten Schraagen
This paper examines team work over time in video-mediated non-collocated and traditional face-to-face same-room teams. In a longitudinal between-groups design, 22 three-person teams were tested in 4 1-h test sessions at 2-week intervals. A paper-folding task was designed for the experiment that had the potential to induce differences in team work under different communication environments. Results showed that near the end of the experiment, initial differences between groups on cooperative task performance in favour of the face-to-face teams had disappeared. These findings are explained in terms of a technological adaptation effect, which occurs when people learn how to use the technological tools available despite technological limitations. No differences were found between groups on cohesion and satisfaction. Likewise, cohesion did not increase over time as participants gained experience. In comparison, satisfaction did increase over time for both groups as teams gained experience with fellow team members and the task at hand. In contrast to what was expected, mental effort was higher for face-to-face teams than for video-mediated teams. Furthermore, initial differences between groups on mental effort did not disappear as participants gained experience. This paper concludes with a discussion of the results in terms of their implications for natural work teams, the design of video-communication technologies and suggestions for future research.
Keywords: Technological adaptation; Video-mediated communication; Team work; Longitudinal design; Telecommunication; Group development; Temporal differences

IJHCS 2005 Volume 62 Issue 5

EDITORIAL

Protege: Community is Everything BIBFull-Text 545-552
  Mark A. Musen

ARTICLE

Cognitive support for ontology modeling BIBAKFull-Text 553-577
  Neil A. Ernst; Margaret-Anne Storey; Polly Allen
Knowledge engineering tools are becoming ever more complex, and therefore increased cognitive support will be necessary to leverage the potential of those tools. Our paper motivates this claim by examining some previous work in this domain and explaining the nature of cognitive support. We discuss some of the problem areas we have encountered in our research. Through user questionnaires and observations carried out at the National Cancer Institute (NCI) and the University of Washington Foundational Model of Anatomy (FMA) Project, we have begun to gain an understanding of the cognitive barriers experienced by the users of knowledge engineering tools. We present some proposed solutions that could address the problems we identified, and in addition, discuss how our own tool, called Jambalaya, could be applied to provide cognitive support. We analyse the support Jambalaya provides using some non-functional design criteria and illustrate some trade-offs inherent in tool design. We suggest that the need for cognitive support in knowledge engineering is immediate and essential.
Keywords: Cognitive support; Knowledge engineering; Information visualization; Requirements engineering
EZPAL: Environment for composing constraint axioms by instantiating templates BIBAKFull-Text 578-596
  Chih-Sheng J. Hou; Mark A. Musen; Natalya F. Noy
Many ontology-development tools allow users to supplement frame-based representations with arbitrary logical sentences. However, few users actually take advantage of this opportunity. For example, in the Ontolingua ontology library, only 20% of the ontologies have any user-defined axioms. We believe the difficulty of composing axioms primarily accounts for the lack of axioms in these knowledge bases: Many domain experts cannot translate their thoughts into abstract and symbolic representations. We attempt to remedy the difficulties by identifying groups of axioms that manifest common patterns, creating "templates" that allow users to compose axioms by "filling in the blanks." We studied axioms in two public ontology libraries, and derived 20 templates that cover 85% of all the user-defined axioms. We describe our methodology for identifying the templates and present examples. We constructed an interface that allows users to create constraints on knowledge bases by "filling in blanks;" our usability testing shows that users could use templates to encode axioms with a success rate similar to that of experts writing directly in an axiom language. Our approach should foster the introduction of axioms and constraints that are currently missing in many ontologies.
Keywords: Frame-based system; Knowledge acquisition; Knowledge representation
Experiences in reusing knowledge sources using Protege and PROMPT BIBAKFull-Text 597-618
  M. Taboada; D. Martinez; J. Mira
We study the general question of how ontologies and reference terminologies can be used to make development of knowledge bases more manageable, taking into account the methodologies and tools available nowadays. For this, we have carried out a case study on designing a knowledge base oriented to support a diagnosis-aid application in ophthalmology. Ideally, starting from a pre-existing domain ontology, development of knowledge bases is centred only on collecting specific knowledge for a particular application. In practice, this is a very time-consuming approach, as ontology repositories do not usually provide many information-seeking facilities. In addition, it is unlikely to find an ontology that includes all the required knowledge. Consequently, design of knowledge bases requires the combination and adaptation of one or more source ontologies. In this work, particular attention is paid to the proper merging of two ontologies using the tool PROMPT. Our study emphasizes the advantages of using PROMPT for merging ontologies containing closely related portions of knowledge, as well as some proposals for improvement. In a second step, our approach extends the evolving ontology, with a new component that holds both a meta-model representing a very simplified structure of a terminology system into Protege-2000 and a set of constraints expressed using the Protege Axiom Language. This set of constraints allows us to check the consistency and coherence of the imported information. Defining meta-classes in Protege-2000 links this component to the rest of the models in the knowledge base. We report our experience in the reuse of several knowledge sources using Protege-2000 and several of the plug-ins.
Keywords: Development of knowledge bases; Ontologies; Terminology systems
Knowledge editing and maintenance tools for a semantic portal in oncology BIBAKFull-Text 619-638
  Mathieu d'Aquin; Christophe Bouthier; Sebastien Brachais; Jean Lieber; Amedeo Napoli
The research work presented in this paper is about the design of a knowledge system architecture applied to oncology and relying on the semantic Web principles. The core of this architecture is a working knowledge system, called Kasimir, using an object-based representation formalism and classification-based reasoning. The ontology editor Protege is connected with the Kasimir system, and is adapted to the particular requirements of Kasimir. The Protege system enables the integration of several editing and visualization modules. A first knowledge editing module relies on classification-based reasoning for detecting mismatches and redundancies in the edited knowledge hierarchy. A second knowledge editing module also uses classification-based reasoning for comparing two versions of the knowledge base for maintenance purposes. This last module is particularly useful for extracting and analysing the changes occurred during an editing session. Three modules are combined to visualize hierarchies, based on three different techniques having complementary advantages. All these modules -- including Kasimir and Protege -- are integrated in a semantic portal architecture based on semantic Web principles. The proposed architecture takes advantage of the semantic Web technologies for integrating the different modules, and for providing a reusable environment for distributed knowledge management in oncology.
Keywords: Knowledge management; Editing; Representation; Reasoning; Maintenance; Visualization; Semantic Web; Semantic portal
PROTEGE as a vehicle for developing medical terminological systems BIBAKFull-Text 639-663
  Ameen Abu-Hanna; Ronald Cornet; Nicolette de Keizer; Monica Crubezy; Samson Tu
A medical terminological system (TS) is essentially an ontology consisting of concepts, attributes and relationships pertaining to medical terms. There are many TSs around today, most of which are essentially frame-based. Various efforts have been made to get a better understanding of the requirements and the conceptual and formal structures of TSs. However, the actual implementation of a TS consisted so far of ad hoc approaches starting from scratch and, due to ad hoc semantics of the representation, the interoperability with external applications of the knowledge represented is diminished. In recent years, protege has been gaining in popularity as a software environment for the development of knowledge-based systems. It provides an architecture for integrating frame-based ontologies with knowledge acquisition and other applications operating on these ontologies. In its recent version, protege provides the ability to specify meta-classes and -slots. This contributes to an explicit separability of knowledge levels and allows for an increased modeling flexibility. These properties, and the fact that it complies with a standard knowledge model, enable protege to be an attractive candidate for the implementation of frame-based TSs. This paper investigates how to specify a TS in protege and demonstrates this in a specific application in the domain of intensive care. Our approach is characterized by the utilization of a conceptual framework for understanding TSs and mapping its components onto protege constructs. This results in specifications of knowledge components for the implementation of terminological systems. The significance of our work stems from the generality of these specifications. This facilitates their reuse, leading to a principled process for the development of terminological systems for a broad spectrum of medical domains.
Keywords: Medical ontologies; Terminological systems; protege; Knowledge representation
GAS Ontology: An ontology for collaboration among ubiquitous computing devices BIBAKFull-Text 664-685
  Eleni Christopoulou; Achilles Kameas
The vision of ubiquitous computing is that the addition of computation and communication abilities to the artefacts that surround people will enable the users to set up their living spaces in a way that will serve them best minimising at the same time the required human intervention. The ontologies can help us to address some key issues of ubiquitous computing environments such as knowledge representation, semantic interoperability and service discovery. The GAS Ontology is an ontology that was developed in order to describe the semantics of the basic concepts of a ubiquitous computing environment and define their inter-relations. The basic goal of this ontology is to provide a common language for the communication and collaboration among the heterogeneous devices that constitute these environments. The GAS Ontology also supports the service discovery mechanism that a ubiquitous computing environment requires. In this paper, we present the GAS Ontology as well as the design challenges that we faced and the way that we handled them. In order to select the language and the tool that we used for the development of the GAS Ontology, we designed a prototype ontology and evaluated a number of languages and tools. The ontology development tool that proved to be the most suitable from this evaluation was Protege-2000. We also present how we use the GAS Ontology in our eGadgets project achieving semantic interoperability and service discovery. Finally, we present the GAS Ontology manager, which runs on each device, manages the device's ontology and processes the knowledge that each device acquires over time.
Keywords: Ontologies; Ubiquitous computing

IJHCS 2005 Volume 62 Issue 6

ARTICLE

GUI objects with impenetrable borders: Instruction (not practice) makes perfect BIBAKFull-Text 687-712
  Keith S. Jones; Brian R. Johnson; J. Shawn Farris
Walker and Smelcer (Proceedings of the CHI 90, ACM, New York, 1990, pp. 221-225) found that menus could be selected faster if they were placed against the edge of the screen. Doing so creates an impenetrable border between the menu and the edge of the screen that the mouse cursor cannot penetrate. This changes how users move the mouse, so that selection times quicken compared to menus with a penetrable border. Experiment 1 investigated the effect that practice has on the acquisition of objects with and without impenetrable borders. The findings suggest that excessive practice was not necessary to demonstrate border type differences; thus, the advantage of having impenetrable borders seems to be relatively instantaneous. However, it was not readily apparent whether or not participants would realize the advantages of impenetrable borders without instruction. Thus, the primary purpose of Experiment 2 was to assess whether or not users would discover the benefits of impenetrable borders spontaneously. Participants were assigned to either the penetrable or impenetrable border condition. Additionally, participants received either full instruction concerning the benefits of the target placement, or limited instruction that simply informed the participant about the nature of the task. The results demonstrated that participants receiving limited instruction selected targets with impenetrable borders faster than participants who selected objects with a penetrable border. However, an exploratory comparison suggests that only 50% of participants who received limited instruction actually detected the impenetrable border. An additional comparison suggests that with practice the participants who were successful at detecting the impenetrable border selected the targets as quickly as participants who received full instruction concerning the benefits of impenetrable borders. The findings suggest that with full instruction, all users will perform reduced selection times. Given that not all participants discovered the impenetrable border it suggests that, whenever possible, users should receive instruction pertaining to the benefits of the impenetrable borders.
Keywords: Impenetrable border; Graphical user interface; Selection
Browsing a document collection represented in two- and three-dimensional virtual information space BIBAKFull-Text 713-736
  S. J. Westerman; J. Collins; T. Cribbin
This paper reports a study of information retrieval performance using an interface in which documents were represented by objects in a virtual environment. Spatial location was determined by semantic content, with inter-object distance representing semantic similarity of documents. The quality of spatial-semantic mapping was manipulated as was the number of dimensions (two versus three) in which document nodes were arranged. Participants were required to browse the information space and identify all documents relevant to a specified topic. Results indicated that participants were able to use three-dimensional spatial mapping of semantic information to facilitate task performance, with performance being better when the quality of the mapping was higher. Strategy differences were identified, with participants adopting a more 'exhaustive' approach when searching two-dimensional node arrangements, and a more 'focused' approach for three-dimensional arrangements. Cognitive ability was not strongly associated with task performance, but participants of relatively lower cognitive ability tended to out-perform those of higher cognitive ability in three-dimensional conditions. Possible reasons for these findings are discussed.
Keywords: Information retrieval; Information visualization; Individual differences
An empirical investigation of sources of application-specific computer-self-efficacy and mediators of the efficacy -- performance relationship BIBAKFull-Text 737-758
  Richard D. Johnson
Integrating theory from research on training, computer self-efficacy (CSE), and motivation, this research validated a model of four factors that contribute to application-specific computer self-efficacy (AS-CSE) formation (previous experience, personality, learning goal orientation and computer anxiety) and three factors that mediate the relationship between AS-CSE and performance (goal level, goal commitment and performance goal orientation (PGO)). Using data from 313 individuals in an introductory computer skills course, the model was validated for database software. Results indicate that previous database software experience, trainee personality and learning goal orientation were positively related to AS-CSE, whereas computer anxiety was negatively related to AS-CSE. Additionally, goal level, goal commitment and PGOs were related to database test performance, and the relationship between AS-CSE and database test performance was also partially mediated by goal level and goal commitment. Implications for research and practice are discussed.
Keywords: Computer self-efficacy; Computer training; Motivation; Goal setting; Goal orientations; Personality; Computer anxiety
Focusing on what might happen and how it could feel: can the anticipation of regret change students' computing-related choices? BIBAKFull-Text 759-783
  Chris Wright; Peter Ayton
A longitudinal study tested whether a regret-based intervention could persuade computer users to make more security-conscious choices in relation to backing up their work and internet security. Computing science students reported their attitudes and behaviour in relation to the two issues at three timepoints (baseline, intervention and follow-up phases) over a 12-week period. In the intervention phase, students imagined themselves in a scenario where, had they chosen to act differently, they could have avoided a negative outcome. They then considered how regretful they would feel in that situation. The results showed that, for backing up, students showed more positive attitudes and data-protective behavioural choices immediately after the intervention and at follow-up, compared to their baseline measures. The second scenario was less effective at changing participants' attitudes and behaviour in relation to disabling active scripting. Possible reasons for the difference in effectiveness of the intervention for the two targeted issues are discussed.
Keywords: Regret; Choice; Decision-making; Computing; Backing-up; Internet security
An extension of Trust and TAM model with TPB in the initial adoption of on-line tax: An empirical study BIBAKFull-Text 784-808
  Ing-Long Wu; Jian-Liang Chen
While on-line tax is considered as a special type of e-service, the adoption rate of this service in Taiwan is still relatively low. The initial adoption of on-line tax is the important driving force to further influence the use and continued use of this service. The model of Trust and technology acceptance model (TAM) in Gefen et al. (2003a, MIS Quarterly 27(1), 51-90) has been well studied in on-line shopping and showed that understanding both the Internet technology and trust issue is important in determining behavioral intention to use. Besides, the diffusion of on-line tax could also be influenced by the potential antecedents such as individuals, organizational members, and social system while the issue for innovative technology is well discussed in Rogers (1995, The Diffusion of Innovation, fourth ed. Free Press, New York). Theory of planned behavior (TPB) is the model widely used to discuss the effect of these antecedents in behavioral intention. An extension of Trust and TAM model with TPB would be in more comprehensive manner to understand behavioral intention to use on-line tax. Furthermore, a large sample survey is used to empirically examine this framework.
Keywords: On-line tax; Trust and TAM model; Trust; TPB