This paper describes a generic approach to structuring and visualising a hypertext-based information space on the WWW. This approach, called Generalised Similarity Analysis (GSA), provides a unifying framework for extracting structural patterns from a range of proximity data concerning three fundamental relationships in hypertext, namely, hypertext linkage, content similarity and browsing patterns. GSA emphasizes the integral role of users' interests in dynamically structuring the underlying information space. Pathfinder networks are used as a natural vehicle for structuring and visualising the rich structure of an information space by highlighting salient relationships in proximity data. In this paper, we use the GSA framework in the study of hypertext documents automatically retrieved over the Internet, including a number of departmental WWW sites and conference proceedings on the WWW. We show that GSA has several distinct features for structuring and visualising hyp...

This article presents two studies concerning the role of individual differences in searching through a spatialsemantic virtual environment. In the first study, 10 subjects searched for two topics through a spatial user interface of a semantic space. A strong positive correlation was found between associative memory (MA-1) and search performance (r # 0.855, p # 0.003), but no significant correlation was found between visual memory (MV-1) and search performance. In the second study, 12 subjects participated in a within-subject experimental design. The same spatial user interface and a simple textual user interface were used. The effects of spatial ability (VZ-2), associative memory (MA-1), and on-line experience were tested on a set of interrelated search performance scores. A statistically significant main effect of on-line experience was found, F(6, 4) # 6.213, p # 0.049, two-tailed. In particular, on-line experience has a significant effect on the recall scores with the textual interface. Individuals experienced in on-line search are more likely to have a higher recall score with the textual interface than less experienced individuals. No significant main effects were found for spatial ability and associative memory. Subjects' comments suggest a potentially complex interplay between individuals' mental models and the high-dimensional semantic model. Qualitative and process-oriented studies are, therefore, called for to reveal the complex interaction between individuals' cognitive abilities, domain knowledge, and direct manipulation skills. A recommendation is made that spatial-semantic models should be adaptable to suit individuals and tasks at various levels

This paper describes a generic approach to the design of a 3D virtual environment for visual navigation. The basic design principle is that users need to understand how an environment is organised and how they can utilise the knowledge to find their way through the environment. In this paper, we focus on the relationship between implicit semantic structures associated with a collection of domain-specific documents and users' cognitive needs in the context of visual navigation. We extend the notion of Pathfinder networks in order to represent implicit semantic structures in a 3D virtual environment. Users' cognitive needs in visual navigation are conceptualised based on the concept of cognitive maps

Software development remains mentally challenging despite the continual advancement of training, techniques, and tools. Because completely automating software development is currently impossible, it makes sense to seriously consider how tools can improve the mental activities of developers apart from automating them away. Such mental assistance can be called “cognitive support”. Understanding and developing cognitive support in software engineering tools is an important research issue but, unfortunately, at the moment our theoretical foundations for it are inadequately developed. Furthermore, much of the relevant research has occurred outside of the software engineering community, and is therefore not easily available to the researchers who typically develop software engineering tools. Tool evaluation, comparison, and development are consequently impaired. The present work introduces a theoretical framework intended to seed further systematic study of cognitive support in the field of software engineering tools. This theoretical framework, called RODS, imports ideas and methods from a field of cognitive science called “distributed cognition”. The crucial concept in RODS is that cognitive support can be understood and explained in terms of the computational advantages that are conferred when cognition is redistributed between software developer and their tools and environment. The name RODS, in fact, comes from the

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In this paper, we investigate the effect of cognitive styles (field dependence) for navigation strategies. The application teaches the use of the database features in Microsoft EXCEL. Two versions of the interface were developed offering free vs constrained hypermedia access to the information. A statistical analysis of the trace revealed important differences of exploration behaviors based on user characteristics. The paper provides extensive studies review and empirical validation for the need to consider cognitive styles to design more adapted user interface. It also highlights the importance of combining a log of user's actions and satisfaction measures, to better understand the user reaction to hypermedia. Keywords: Field dependence, cognitive styles, navigation strategies, information processing, computer-based instruction. 1. INTRODUCTION The field of computer technologies has exploded since we started to focus on human factors, in order to build more user-friendly interf...

This paper presents two studies of the use of the WWW in Scottish universities and American land-grant universities. First, we investigated the relationship between the organisational profile of a university department in Scotland and its structural connectivity on the WWW. A Spearman rank order correlation analysis revealed a number of strong correlation relationships between structural connectivity measures and the organisational profile based on research assessment exercise ratings, teaching quality assessments, student--staff ratios and funding levels. Linkage patterns from 13 Scottish academic sites to commercial sites in Britain and America highlighted the impact of culture and the appropriateness of information technologies on the acceptance of the WWW. The second study is a content survey of WWW-based education activities in American land-grant universities to investigate successful applications of these enabling techniques in education. The two studies together highlighted cultural, political and technological interactions in the use of the WWW.

this article, we present a brief historical overview of research in individual differences in the context of virtual environments. In particular, we highlight the notion of structure in the perception of individual users of an information system and the role of individuals ' abilities to recognize and use such structures to perform various information-intensive tasks. Striking the balance between individuals' abilities and the demanding task for detecting, understanding, and utilizing such structures is an emerging theme across the five articles in this special issue. We outline the approaches and the major findings of these articles with reference to this central theme

This document layout approach answers the need for dealing with documents which were only processed by an OCR program. This technique also makes use of font types and bold print, identifying these as better candidates for anchors. One problem with this approach is that it depends on the linear structure of the documents and that it maintains this very same structure after the text to hypertext conversion (Myka, Argenton and Güntzer, 1996). Following Richmond, Smith and Amitay (1997), a combined approach might be taken. The authors suggest a simple algorithm for detecting subject boundaries within flat texts. The algorithm also finds topical words in each segment, enabling the detection of content and context. It also disambiguates the necessary words by allowing access to their immediate 32

Current Network User Interfaces (NUIs) provide entrances to an enormous amount of Web-based services, bringing about new use problems such as laborious and unsuccessful navigation. Such problems are generally more severe for users with regression of cognitive functions (e.g. for some elderly). This paper identifies four fundamental cognitive determinants of navigation performance that may explain these problems: situation awareness, spatial ability, task-set switching and user control of support. Based on an analysis of these demands and current support functions for navigation, three "refined" support concepts were developed: categorising landmarks, history map and navigation assistant. Via the specification of humancomputer co-operative processes and scenarios, the concepts were implemented for two rather different web-based services. The present paper provides an example implementation of the navigation assistant. The results of the study will feed into a cognitive engineering method for the design of NUIs. Keywords Network user interface, World Wide Web, cognitive engineering, usability, navigation.