| The rising pitch metaphor: an empirical study | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | |||
| Special issue on subtle expressivity for characters and robots | | BIB | Full-Text | 159-160 | |
| Noriko Suzuki; Christoph Bartneck | |||
| Computers that care: investigating the effects of orientation of emotion exhibited by an embodied computer agent | | BIBAK | Full-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 | | BIBA | Full-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 | | BIBA | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | |||
| Presence, memory and interaction in virtual environments | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 to: "The production and recognition of emotions in speech: features and algorithms": [Int. J. Hum.-Comput. Stud. 59 (2003) 157] | | BIB | Full-Text | 423 | |
| Pierre-Yves Oudeyer | |||
| Time-related behaviour in multitasking situations | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | |||
| Protege: Community is Everything | | BIB | Full-Text | 545-552 | |
| Mark A. Musen | |||
| Cognitive support for ontology modeling | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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 | |||
| GUI objects with impenetrable borders: Instruction (not practice) makes perfect | | BIBAK | Full-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 | | BIBAK | Full-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 | | BIBAK | Full-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? | | BIBAK | Full-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 | | BIBAK | Full-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 | |||