Showing papers in "International Journal of Human-computer Studies \/ International Journal of Man-machine Studies in 2002"

Animation: can it facilitate?

Abstract: Graphics have been used since ancient times to portray things that are inherently spatiovisual, like maps and building plans. More recently, graphics have been used to portray things that are metaphorically spatiovisual, like graphs and organizational charts. The assumption is that graphics can facilitate comprehension, learning, memory, communication and inference. Assumptions aside, research on static graphics has shown that only carefully designed and appropriate graphics prove to be beneficial for conveying complex systems. Effective graphics conform to the Congruence Principle according to which the content and format of the graphic should correspond to the content and format of the concepts to be conveyed. From this, it follows that animated graphics should be effective in portraying change over time. Yet the research on the efficacy of animated over static graphics is not encouraging. In cases where animated graphics seem superior to static ones, scrutiny reveals lack of equivalence between animated and static graphics in content or procedures; the animated graphics convey more information or involve interactivity. Animations of events may be ineffective because animations violate the second principle of good graphics, the Apprehension Principle, according to which graphics should be accurately perceived and appropriately conceived. Animations are often too complex or too fast to be accurately perceived. Moreover, many continuous events are conceived of as sequences of discrete steps. Judicious use of interactivity may overcome both these disadvantages. Animations may be more effective than comparable static graphics in situations other than conveying complex systems, for example, for real time reorientations in time and space.

Understanding user acceptance of digital libraries: what are the roles of interface characteristics, organizational context, and individual differences?

Abstract: Digital library research efforts originating from library and information scientists have focused on the technical development. While millions of dollars have been spent on building "usable" digital libraries, previous research indicates that potential users may still not use them. This study contributes to understanding user acceptance of digital libraries by utilizing the technology acceptance model (TAM). Three system interface characteristics, three organizational context variables, and three individual differences are identified as critical external variables that have impact on adoption intention through perceived usefulness and perceived ease of use of the digital library. Data was collected from 397 users of an award-winning digital library. The findings show that both perceived usefulness and perceived ease of use are determinants of user acceptance of digital libraries. In addition, interface characteristics and individual differences affect perceived ease of use, while organizational context influences both perceived ease of use and perceived usefulness of digital libraries.

Interactive machine learning: letting users build classifiers

Abstract: According to standard procedure, building a classifier using machine learning is a fully automated process that follows the preparation of training data by a domain expert. In contrast, interactive machine learning engages users in actually generating the classifier themselves. This offers a natural way of integrating background knowledge into the modelling stage—as long as interactive tools can be designed that support efficient and effective communication. This paper shows that appropriate techniques can empower users to create models that compete with classifiers built by state-of-the-art learning algorithms. It demonstrates that users—even users who are not domain experts—can often construct good classifiers, without any help from a learning algorithm, using a simple two-dimensional visual interface. Experiments on real data demonstrate that, not surprisingly, success hinges on the domain: if a few attributes can support good predictions, users generate accurate classifiers, whereas domains with many high-order attribute interactions favour standard machine learning techniques. We also present an artificial example where domain knowledge allows an “expert user” to create a much more accurate model than automatic learning algorithms. These results indicate that our system has the potential to produce highly accurate classifiers in the hands of a domain expert who has a strong interest in the domain and therefore some insights into how to partition the data. Moreover, small expert-defined models offer the additional advantage that they will generally be more intelligible than those generated by automatic techniques.

Multimedia design for communication of dynamic information

Abstract: Computer-based multimedia technologies allow designers to construct interactive and animated graphical presentations to communicate dynamic information. The conventional wisdom is that such presentations are more effective than printed materials. This paper presents research that critically examines this assumption. Design guidelines and principles were derived from a cognitive process model of multimodal comprehension. These guidelines and principles were used to create several expository presentations in two domains—the concrete domain of mechanical systems and the abstract domain of computer algorithms. A series of experiments evaluated the efficacy of these presentations and compared them with other kinds of presentations such as books, CD-ROMs and animations. The experiments also compared computer-based interactive graphical presentations and static printed presentations containing the same information. Experimental results suggest that the communicative efficacy of multimodal presentations is more related to their match with comprehension processes than with the interactivity and dynamism of the presentation media. The results support a model-based approach to the design of multimodal expository presentations of dynamic information. The comprehension model and corresponding design guidance should aid designers in building interactive graphical presentations that are more effective than intuitive designs in communicating dynamic content.

Learner outcomes in an asynchronous distance education environment

Abstract: This research investigated student outcomes in a web-based distance learning environment characterized by asynchronous electronic communications between student and teacher. We employed two dominant theories?the theory of planned behavior and innovation diffusion theory?to study student reactions to web-based distance education. We hypothesized that student perceptions of the technology are positively related to learning outcomes and intentions to further use the technology, and are negatively related to using alternative, synchronous media in the learning experience. Quantitative and qualitative data were gathered from 540 students via a web-based survey. Partial support was found for the hypotheses. Theoretical and practical implications for human?computer interaction, distance education and user acceptance are discussed.

Virtual team interaction styles

Abstract: The virtual team is an increasingly common strategic work unit of many organizations. The virtual team, via various computer-based media (e.g. email, groupware) and noncomputer-based media (e.g. telephone), can interact and collaborate though separated by distance and time. One approach to their study is determining whether factors that drive conventional team performance also exist in the virtual environment. Interaction style has been shown to have a great effect on conventional teams' ability to achieve solution quality and solution acceptance on collaborative decision tasks (Hirokawa, 1985; Watson & Michaelsen 1988; Hirokawa & Gouran, 1989; Cooke & Szumal, 1994). Group interaction styles affect communication and thus team performance by facilitating or hindering the exchange of information among group members. These styles reflect an aggregation of behavioral traits of individual team members, rooted in their individual personalities. The interaction style of conventional teams can be reliably assessed, and from that assessment, performance on collaborative decision tasks can be predicted. This study investigated whether or not virtual teams who collaborate via computer-mediated communication also exhibit similar interaction styles, and whether the styles have the same effects on their decision performance and process outcomes as they do with conventional teams. Members of 42 virtual teams completed an intellective decision first individually and then collaboratively. Post-task measures captured individual and team performance data (e.g. solution quality) as well as process perceptions (individual acceptance of the team solution). An additional post-task tool was able to accurately capture the teams' interaction style. Results show that the interaction styles of virtual teams affect both performance and process outcomes in ways that are directionally consistent with those exhibited by conventional face-to-face teams. Implications include recommending the methodology for virtual team management, and suggestions for future research are offered.

The effects of graphic organizers giving cues to the structure of a hypertext document on users' navigation strategies and performance

Abstract: Two experiments examined the effects of graphical organizers on users' navigation of a 150-page hierarchical website of aquatic animals. In Experiment 1, users were given either a non-clickable map (map group) or no map (no-map group) and answered 30 questions by searching the website. The map group was more efficient (visited fewer pages) on the first 20 questions (learning phase) but the no-map group was marginally more efficient on the last 10 questions (test phase), and displayed more flexible search strategies. In Experiment 2, users were either given a simplified organizer locating the current page in the website (explicit group) or an alphabetized list of superordinate pages (implicit group). The task from Experiment 1 was repeated. No differences in efficiency were found, but the explicit group was faster than the implicit group in the test phase. The results depended on individual differences in spatial skills. These results suggest a tradeoff between organizers that are useful initially and those that promote structural learning.

Understanding the materiality of writing from multiple sources

Abstract: Writing research has typically focussed on the text production elements of writing. Many everyday writing tasks, however, cannot be characterized simply in terms of text production since they often involve the use of source materials to support the composition process. As such, these tasks are better thought of as hybrid tasks. Such hybrid tasks have been given relatively little attention in the literature and what little work has been done has taken a purely cognitive approach that downplays the material context within which the task takes place. Following Haas' critique of mainstream writing research which advocated the need to consider the material tools and artefacts in theories of writing, this paper takes a similar approach in relation to the hybrid tasks of writing while reading from multiple sources. A study is presented that explores a range of everyday writing from multiple sources in their real-world contexts. The study highlights a number of important characteristics of the interaction with the material artefacts used during these tasks and the impact that these have on the underlying cognitive processes. The hope is that these will begin to offer some grounding on which future theoretical understanding of these hybrid tasks can build, as well as providing useful insights into the design of technologies to support these tasks.

Vision-based user interfaces: methods and applications

Abstract: Within the class of perceptive user interfaces (i.e. interfaces providing the computer with perceptive capabilities), artificial vision is being exploited more and more as a new input modality, in addition to or in replacement of standard interaction paradigms. The aim of this paper is to provide a global view on the field of vision-based interfaces (VBIs), through the analysis of the methods used for their implementation and the exploration of the practical systems in which they have been employed. The focus will mostly be on techniques and prototypes intended for office and home PC-based use, as we are mainly interested in vision technology applied to ordinary computing environments. After a brief introduction to basic concepts about interfaces and image processing, the attention will be shifted to the four main areas in which VBIs find their maximum expression, namely head tracking, face/facial expression recognition, eye tracking and gesture recognition.

Preventing user errors by systematic analysis of deviations from the system task model

Abstract: Interactive safety-critical applications have specific requirements that cannot be completely captured by traditional evaluation techniques. In this paper, we discuss how to perform a systematic inspection-based analysis to improve both usability and safety aspects of an application. The analysis considers a system prototype and the related task model and aims to evaluate what could happen when interactions and behaviours occur differently from what the system design assumes. We also provide a description and discussion of an application of this method to a case study in the air traffic control domain.

Virtual team awareness and groupware support

Abstract: This paper overviews a Web-based collaborative system called TeamSCOPE that has been designed to support awareness needs of globally distributed teams. Four types of awareness needs of virtual teams are defined and the awareness support features of TeamSCOPE are described. The usage patterns of eight globally distributed engineering design teams are outlined, and evaluation results are provided. Findings illustrate how group process interacts with technology to create design challenges in the support of virtual team awareness needs.

Interacting with the telephone

Abstract: This paper describes an empirical study of the use of a mundane domestic technology?the telephone. It combines qualitative and quantitative data gathered as part of a longitudinal study of a panel of 2400 individuals distributed across 1000 UK households. It uses this data to build a rich picture of the ways in which people use the telephone in the late 1990s highlighting the way in which factors such as roles, location, life rhythms and in particular, gender, influence patterns of use and interaction for social purposes. The paper then discusses how these findings are of significance at various levels from the identification of specific design requirements to the conception of what user centred design is and can be in the consumer market.

A cooperative framework for integrating ontologies

Abstract: Nowadays, there are systems and frameworks that support Ontology construction processes. However, ontology integration processes have not sufficiently been specified to date. In this article, by making use of a cooperative philosophy, we describe a real framework for the integration of ontologies supplied by a predetermined set of (expert) users, who may be interconnected through a communication network. This framework is based on a set of well-defined assumptions that guarantee the consistency of the ontology derived from the ontology integration process. Moreover, in the approach presented here, every (expert) user may consult the so-derived ontology constructed until a given moment in order to refine his or her private ontology. In addition to this, the model proposed in this work allows the experts involved in the construction of the ontology to use their own terminology when querying the global ontology obtained until a given instant from their own co-operative work. The validation of the framework is also included in this work.

BlueSpace: personalizing workspace through awareness and adaptability

Abstract: This paper reports on research in workplace issues encountered by knowledge workers in cubicle environments, and on BlueSpace, a prototype workspace with the goal of addressing workers' critical needs for privacy, concentration and personalization. To inform the design process, more than 50 on-site interviews with knowledge workers were conducted at six companies ranging from dot.com startups to Fortune 100 corporations. Several common requirements emerged including the need for a sense of control of one's workspace, the ability to create privacy on-demand to improve concentration and minimize unwanted interruptions, as well as in-place support for dyadic interactions. Many other common workplace complaints (e.g. too hot, too cold, too noisy) were found to be derivative of the major requirements for individual control and privacy.

Supporting on-line resource discovery in the context of ongoing tasks with proactive software assistants

Abstract: We present ongoing work on systems aimed at improving a user's awareness of resources available to them on the Internet and in intranets. First, we briefly describe Watson, a system that proactively retrieves documents from on-line repositories that are potentially useful in the context of a task, allowing the user to quickly become aware of document resources available in on-line information repositories. Next, we describe I2I, an extension of Watson that builds communities of practice on the fly, based on the work that its users do, so that users with similar goals and interests can discover each other and communicate both synchronously and asynchronously. Both Watson and I2I operate given some knowledge of the user's current task, gleaned automatically from the behavior of users in software tools. As a result, the systems can provide users with useful resources in the context of the work that they are performing. We argue that the systems can foster a greater sense of awareness of the resources available, while minimizing the effort required to discover them.

Pushing back: evaluating a new behaviour for the back and forward buttons in web browsers

Abstract: The Back button on web browsers is one of the world's most heavily used user interface components, yet its behaviour is commonly misunderstood. This paper describes the evaluation of a "temporal" alternative to the normal "stack-based" behaviour of Back and Forward. The main difference of the temporal scheme is that it maintains a complete list of previously visited pages. The evaluation compares the efficiency of the stack and temporal schemes in an "out of the box" scenario in which participants were asked to use a "new" version of a commercial browser without any explanation of the presence or absence of new features. This scenario allows us to predict the likely usability impact if commercial browsers were released supporting the temporal scheme. The results showed that the relative efficiency of the two schemes differed across different types of navigational task. In particular, the temporal system poorly supported backtracking to parent pages, but performed better for more distant navigation tasks. The temporal scheme also caused extreme usage patterns, with the subjects either solving tasks very efficiently or very inefficiently, depending on whether they used the Back menu. This observation indicates that adaptations of the temporal system that improve the effectiveness of the Back menu may enhance web navigation.

Instant messaging with WebWho

Abstract: We present a study of how awareness of presence affects content of instant messaging sent between students using WebWh o, an easily accessible web-based awareness tool. WebWho visualizes where people are located in a large university computer lab and allows students to virtually locate one another and communicate via an instant messaging system. As WebWho is there to be accessed through any web browser, it requires no programming skills or special software. It may also be used from outside the computer lab by students located elsewhere. The sender's user name is normally automatically added to the instant messages, but the messages can also be sent anonymously. We were interested in finding out if the sender's conscious hiding of his or her identity seemed to be reflected in the content of anonymous messages, and how these differed from those with identified senders. Awareness of presence seems to be one of several factors influencing message composition, both content and structural aspects. At this stage, we have primarily focused on examining how different factors affects the content of the messages. We cross-analysed the messages for content in relation to parameters such as sender location (collocated, distributed and distant) and sender status (anonymous vs. identified), in order to find out whether awareness of presence seems to be an influencing factor. Computer-mediated communication (CMC) is often claimed to be a sort of hybrid between spoken and written interaction c.f. Ferrara, Brunner & Whittemore (1991) and and several others]. We compared the messages that were sent using the instant messaging tool in WebWho with data from other types of CMC (email, chat) and also with corpora of spoken language and traditionally written language. The aim of the study was primarily to investigate awareness of presence affects on instant messaging, and only secondarily to investigate spoken vs. written features of the texts. Results show that awareness of both physical and virtual presence affects the content of the messages, and that these factors affects the text differently. Sender status, the nature of the computer-mediated medium, and the written mode shape the messages as well. Results show that the students use the messaging system to support collaborative work and coordinate social activities, and extensively for playful behaviour.

Supporting the awareness of shared interests and experiences in communities

Abstract: In this paper, we propose a notion of facilitating encounters and knowledge sharing among people having shared interests and experiences in museums, conferences, etc. In order to show our approach and its current state, this paper presents our project to build a communityware system situated in real-world contexts. The aims of the project are to build a tour guidance system personalized according to its user's individual contexts, and to facilitate knowledge communications among communities by matchmaking users having shared interests and providing real and/or virtual places for their meetings. In this paper, we first show PalmGuide, a hand-held tour guidance system. After that, we show two systems designed to increase the level of “community awareness”. One is called Semantic Map, a visual interface for exploring community information, such as exhibits and people (focusing on exhibitors and visitors). The other is called AgentSalon, a display showing conversations between personal agents according to their users' profiles and interests.

F an

Abstract: In this paper we present a machine-learning algorithm that computes a small set of accurate and interpretable rules. The decisions of these rules can be straight-forwardly explained as the conclusions drawn by a case-based reasoner. Our system is named F AN, an acronym for f inding a ccurate i n ductions. It starts from a collection of training examples and produces propositional rules able to classify unseen cases following a minimum-distance criterion in their evaluation procedure. In this way, we combine the advantages of instance-based algorithms and the conciseness of rule (or decision-tree) inducers. The algorithm followed by F AN can be seen as the result of successive steps of pruning heuristics. The main tool employed is that of the impurity level, a measure of the classification quality of a rule, inspired by a similar measure used in IB3. Finally, a number of experiments were conducted with standard benchmark datasets of the UCI repository to test the performance of our system, successfully comparing F AN with a wide collection of machine-learning algorithms.

Graphical representation in graphical dialogue

Abstract: This paper explores the influence of communicative interaction on the form of graphical representations. A referential communication task is described which involves exclusively graphical dialogue. In this task subjects communicate about pieces of music by drawing. The drawings produced fall into two basic types: and Figurative. Three hypotheses are developed about the factors influencing the use of these drawing types: efficiency of production, suitability for the task and level of communicative interaction. Experimental evidence is presented which indicates that the drawing types do not differ in the amount of effort required to produce them. The results indicate that (1) drawings are more effective than Figurative drawings for comparative tasks and (2) a key constraint on their use is level of direct communicative interaction. It is argued that these observations result from differences in the underlying semantic models of music associated with the drawing types and the consequences these differences have for communicative coordination.

Relational attribute systems

Abstract: We introduce a relational operationalization of data which generalizes, among others, the deterministic information systems of Pawlak (1982), the indeterministic systems of Lipski (1976) and Or?owska and Pawlak (1987), and the context relations of Wille (1982); it can also be used for fuzzy data modelling. Using an example from the area of psychometrics, we show how our operationalization can lead to an improved understanding of agreements and disagreements by experts in classification tasks. Copyright 2001 Academic Press.“Das Merkwurdigste an einem Loch ist der Rand”.?(Tucholsky, 1975)

A methodological approach to supporting organizational learning

Abstract: Many organizations need to respond quickly to change and their workers need to regularly develop new knowledge and skills. The prevailing approach to meeting these demands is on-the-job training, but this is known to be highly ineffective, cause stress and devalue workplace autonomy. Conversely, organizational learning is a process through which workers learn gradually in the work context through experience, reflection on work practice and collaboration with colleagues. Our approach aims to support and enhance organizational learning around enriched work representations. Work representations are tools and documents used to support collaborative working and learning. These are enriched through associations with formal knowledge models and informal discourse. The work representations, informal discourse and associated knowledge models together form on organizational memory from which knowledge can be retrieved later. Our methodological approach to supporting organizational learning is drawn from three industrial case studies concerned with machine maintenance, team planning and hotline support. The methodology encompasses development and design activities, a description of the roles and duties required to sustain the long-term use of the tools, and applicability criteria outlining the kind of organizations that can benefit from this approach.

Editorial: awareness and the WWW

Abstract: Over the last decade, the issue of awareness has received increasing attention from practitioners in academia and industry. This applies to researchers from various horizons, and in particular from the Computer Supported Cooperative Work (CSCW), the Human–Computer Interaction (HCI) and the World Wide Web (WWW) communities. Nevertheless, awareness has remained a somewhat fuzzy concept, for which there exists no single, unequivocal definition. True, awareness is often meant as awareness of other people, and refers to the ability to maintain some knowledge about the situation and activities of others. There is also a tacit agreement that maintaining this knowledge should not require much effort or, in other words, that awareness should happen as ‘‘naturally’’ as possible. Supporting technology should be designed with this aim, which explains why human–computer interaction issues are of prime concern. Research has exhibited a wide spectrum of situations, in the context of which ‘‘awareness’’ can take very different meanings. Rather than to speak about awareness as such, it is therefore more appropriate to speak about particular types of awareness. For instance, group awareness can be defined as the ability that peers may have to stay in touch and to keep track of each others activities. The information that group members maintain about each other may not be very consequent, nor very precise. Having only a general idea of what is happening, or merely that something is happening, is often already very valuable. Let us be clear about it: the realization of group awareness may not require any technology support at all. When people share the same room, they naturally produce and interpret a constant flow of subtle cues with this aim. Glancing at someone may be enough to decide whether it is appropriate or not to start a conversation. On the other hand, when the members of a group are scattered across space and time, technology may offer surrogates to this natural process}media spaces are an example for such technology. Obviously, groups formed in the context of the workplace greatly benefit from increased awareness. Communication and collaboration are easier, cooperation is smoother and, as a result, work processes are more efficient.

Expertise and the interpretation of computerized physiological data: implications for the design of computerized monitoring in neonatal intensive care

Abstract: This paper presents the outcomes from a cognitive engineering project addressing the design problems of computerized monitoring in neonatal intensive care. Cognitive engineering is viewed, in this project, as a symbiosis between cognitive science and design practice. A range of methodologies has been used: interviews with neonatal staff, ward observations and experimental techniques. The results of these investigations are reported, focusing specifically on the differences between junior and senior physicians in their interpretation of monitored physiological data. It was found that the senior doctors made better use of the different knowledge sources available than the junior doctors. The senior doctors were able to identify more relevant physiological patterns and generated more and better inferences than did their junior colleagues. Expertise differences are discussed in the context of previous psychological research in medical expertise. Finally, the paper discusses the potential utility of these outcomes to inform the design of computerized decision support in neonatal intensive care.

Work domain analysis and sensors II: pasteurizer II case study

Abstract: In this paper we use sensor-annotated abstraction hierarchies (Reising & Sanderson, 1996, 2002a, b) to show that unless appropriately instrumented, configural displays designed according to the principles of ecological interface design (EID) might be vulnerable to misinterpretation when sensors become unreliable or are unavailable. Building on foundations established in Reising and Sanderson (2002a) we use a pasteurization process control example to show how sensor-annotated AHs help the analyst determine the impact of different instrumentation engineering policies on a configural display that is part of an ecological interface. Our analyses suggest that configural displays showing higher-order properties of a system are especially vulnerable under some conservative instrumentation configurations. However, sensor-annotated AHs can be used to indicate where corrective instrumentation might be placed. We argue that if EID is to be effectively employed in the design of displays for complex systems, then the information needs of the human operator need to be considered while instrumentation requirements are being formulated. Rasmussen's abstraction hierarchy--and particularly its extension to the analysis of information captured by sensors and derived from sensors--may therefore be a useful adjunct to upstream instrumentation design.

Evolution of interactive graphical representations into a design language: a distributed cognition account

Abstract: This study investigates the evolution of the graphical representations used to specify information systems in a community of novice designers supported by a shared design memory, adopting the paradigm of distributed cognition. The nature of the relationship between design notations, quality of design and communication is explicated by considering the interplay of actors, representations, design task and an evolving social and cultural context. An account is provided of how meaningful representational features are transmitted and transformed across generations of designers, and combined in a design language that improves design quality and accommodates varied communication needs and interactional constraints. Diffusion and creation of novel representational features start from a process of critical imitation steered by criteria of instrumental utility set by the individual design teams to address both their needs, concerning level of understanding and desired expressiveness of the design, and the socially regulated expectations about what is required in a good design. These tendencies result in an organizational phenomenon according to which the language of the community evolves by incorporating more sophisticated representational modes, i.e. patterns of features that are used in a socially clever way, in particular to reduce the cognitive load involved in interpretation, and to sustain interaction with the instructor during the exam. It is argued that the cognitive fit between the general characteristics of design task and the expressive modalities allowed by the medium used for the design specifications, plus the individual differences between the novice designers are key factors in sustaining the evolution of the language.

A comparison of the affordances of a digital desk and tablet for architectural image tasks

Abstract: The physical context of architectural design includes large workspaces, typically drafting tables covered with piles of images and sketches. We are investigating if and how a large computerized workspace can be integrated usefully into such a design environment. To this end, we compared a large computerized desktop (digital desk) to a standard desktop computer and a small tablet environment for two typical architecture design tasks: sketching and image sorting. For the sketching task, the participants' preferences were evenly divided between the digital desk and the tablet. For the image sorting task, the desk was the least preferred environment, and produced significantly higher sorting times and more mistakes. Investigation into the causes of this difference yielded several interesting findings, including: the height of the participant was significantly associated with their speed on the sorting task, the larger image size available on the desk compensated for its poorer resolution in subjective preferences, and the quality of the alignment of the pen was an important factor both for preference and scoring results in the sketching task. Highly responsive pen input devices seem critical for user satisfaction not only for sketching, but also for image sorting; the effects of large display spaces are difficult to isolate from the limitations of input device. This paper elaborates on these findings and considers the implications for the design of user interfaces for image manipulation, in particular interaction techniques appropriate to using pen-input with large display surfaces.

Visual search strategies and eye movements when searching Chinese character screens

Abstract: Most visual search studies have been restricted to alphanumeric stimulus materials. Research related to scanning patterns of Chinese characters is sparse. This study is an attempt to understand the differences and similarities in visual search of Chinese characters having a varying degree of complexity among Hong Kong Chinese, Mainland Chinese and Chinese reading non-Chinese people. Eighteen participants were tested on Chinese character screens with three layouts (row, column, and uniform separation) and two word complexities (high and low). The 18 participants comprised six Hong Kong Chinese, six Mainland Chinese and six non-native Chinese readers. Performance data and eye movement data were recorded. The percent correct and search time were the two performance measures. A new measure, called HV-ratio was developed to characterize eye movements. The results show that Hong Kong Chinese use predominantly horizontal search patterns while the Mainland Chinese change their search pattern depending on the layout presented. Non-native Chinese readers, on the other hand, do not seem to show any preference on scanning strategy for a given layout. Word complexity did not show any significant effect on search time. Potential reasons for these differences and design implications are discussed.

Work domain analysis and sensors I: principles and simple example

Abstract: In this paper we establish a foundation for understanding the instrumentation needs of complex dynamic systems if ecological interface design (EID)-based interfaces are to be robust in the face of instrumentation failures. EID-based interfaces often include configural displays which reveal the higher-order properties of complex systems. However, concerns have been expressed that such displays might be misleading when instrumentation is unreliable or unavailable. Rasmussen's abstraction hierarchy (AH) formalism can be extended to include representations of sensors near the functions or properties about which they provide information, resulting in what we call a "sensor-annotated abstraction hierarchy". Sensor-annotated AHs help the analyst determine the impact of different instrumentation engineering policies on higher-order system information by showing how the data provided from individual sensors propagates within and across levels of abstraction in the AH. The use of sensor-annotated AHs with a configural display is illustrated with a simple water reservoir example. We argue that if EID is to be effectively employed in the design of interfaces for complex systems, then the information needs of the human operator need to be considered at the earliest stages of system development while instrumentation requirements are being formulated. In this way, Rasmussen's AH promotes a formative approach to instrumentation engineering.

Applying models of visual search to menu design

Abstract: The Guided Search (GS) model, a quantitative model of visual search, was used to develop menu designs in a four-step process. First, a GS simulation model was defined for a menu search task. Second, model parameters were estimated to provide the best fit between model predictions and experimental data. Third, an optimization algorithm was used to identify the menu design that minimized model predicted search times based on predefined search frequencies of different menu items. Fourth, the design was tested. The results indicate that the GS model has the potential to be part of a system for predicting or automating the design of menus. # 2002 Elsevier Scince Ltd.