Bookmarks are used as "personal Web information spaces" to help people remember and retrieve interesting Web pages. A study of personal Web information spaces surveyed 322 Web users and analyzed the bookmark archives of 50 Web users. The results of this study are used to address why people make bookmarks, and how they create, use, and organize them. Recommendations for improving the organization, visualization, representation, and integration of bookmarks are provided. The recommendations include simple mechanisms for filing bookmarks at creation time, the use of time-based visualizations with automated filters, the use of contextual information in representing bookmarks, and the combination of hierarchy formation and Web page authoring to aid in organizing and viewing bookmarks.

Multimedia technologies are being adopted both in the professional and commercial world with great enthusiasm. This has led to a significant interest in the research and development of multimedia databases. However, none of these efforts have really addressed the issues related to the benchmarking of multimedia databases. We analyze the problem of benchmarking multimedia databases in this paper and suggest a methodology.

Reading of electronic documents is becoming increasingly important as more information is disseminated electronically. We present an experiment that compares the usability of a linear, a fisheye, and an overview+detail interface for electronic documents. Using these interfaces, 20 subjects wrote essays and answered questions about scientific documents. Essays written using the overview+detail interface received higher grades, while subjects using the fisheye interface read documents faster. However, subjects used more time to answer questions with the overview+detail interface. All but one subject preferred the overview+detail interface. The most common interface in practical use, the linear interface, is found to be inferior to the fisheye and overview+detail interfaces regarding most aspects of usability. We recommend using overview+detail interfaces for electronic documents, while fisheye interfaces mainly should be considered for timecritical tasks.

AURALIZATION OF DOCUMENT STRUCTURE Steve Portigal Advisor: University of Guelph, 1994 Professor T. Carey An experiment compared the effectiveness of auditory, visual, and combination cues to convey document structure. Subjects demonstrated an equivalent level of understanding of the document structure and its content with either a combination cue or a visual cue. Subjects required more time to answer questions in the combination condition than in the visual condition. This suggests a greater cognitive effort is required. A sound-only condition has the poorest performance both in response time and in the subject's answers to questions about the document's structure and its content. Subjects were grouped based on whether or not they replayed sounds as a retention tactic. Subjects who replayed sounds did better than subjects who did not. These results contribute to our understanding of potential uses of sound in user interfaces. The specific cues used here for this particular task do not ...

My overall objective is to develop and evaluate ways of automatically incorporating hypertext links into pre-existing scholarly journal articles. I describe a rule-based approach for making three types of links (structural, definition, and semantic). Structural links are a way of making explicit some connections between parts of the text. Definition links connect the use of a term, defined elsewhere in the document, to that definition. Links that connect parts of text that discuss similar things are semantic links. I distinguish several types of semantic links. I use two information retrieval (IR) systems (Cornell's SMART system and Bellcore's Latent Semantic Indexing) to select links based on the content of the articles. I conducted an experiment to compare the performance of the links forged using these two systems. The effectiveness of the links (and the rules used to make them) is tested by people reading the hypertext versions for information under a time constraint. A within-subj...

Abstract. Adaptive navigation support can be of great help in large hypermedia systems supporting learners as well as users searching for specific information. A wide variety of adaptive mechanisms have been implemented in existing adaptive hypermedia systems that provide better and better suggestions to the user what hyperlinks to follow. We suggest that adaptive navigation support should scaffold a learner in an educational hypermedia system to select the appropriate links. We show that this implies that selecting a link is an educationally relevant activity that should not always be reduced to a trivial task by powerful adaptive mechanisms. It follows that learners require sometimes different kinds of adaptive navigation support than users looking for information. Finally, we will suggest how to extend current mechanisms to provide scaffolded navigation support to learners. 1

The vast majority of college students have been reared as researchers in an environment where boundaries for information have been clearly marked, i.e., that of books and paper text. Increasingly, however, they are called upon to perform tasks in an environment not clearly bounded, that of hyperspace. How do we learn to surf in this unfamiliar medium? What strategies do people use when surfing through the unbounded space of hyperlinks or the World Wide Web (WWW)? In order to effectively teach students new surfing skills we must be able to understand how neophyte web users form the cognitive neurological networks that result in a mental pathway, or cognitive map, that makes more navigable the route to further information as well as the information they set out to find. A markovian modeling of user's behavior is introduced and compared to a fuzzy cognitive map (FCM) that represents the opinions of experts on how users surf the web. Experts are divided on what causes users to fail their queries on the web. This paper shows that a viable FCM model can be developed and some limit-cycle equilibria are uncovered. A FCM limit cycle repeats a sequence of events and actions. Limit cycles can reveal cognitive and behavioral patterns of users on the web. An adaptive FCM is built to reflect its causal behavior in time.

We propose a systematic process for the design of user interfaces for hypertext systems, within the context of a general purpose semantic &mework for hypertext junctionaN @ Although a number of guidelines exist to enhance the usability of interactive systems, there has been no systematic and comprehensive approach to the design of self-evident interfaces for hypertext Systems. We believe that there is a strong need for such an approach to user interface design for hypertext ystems that should also include the semantic types of the underlying objects. This will not only reduce functional opacity but also system opacity. We present examples porn a screen prototyp to illustrate our design methodology.

this paper, we discuss the design and construction of a particular type of electronic publication that has gained recent popularity: electronic conference proceedings. We suggest that modern electronic proceedings should provide a high degree of interactivity. In part, this interactivity is supported by a variety of annotation, presentation, and retrieval mechanisms. Video components and support systems for these components can further enhance interactivity. Of particular value to electronic conference proceedings are video and related materials from conference presentations. Contents

this paper, we present a new approach to the classification and visualization of navigation behavior that provides the researcher with quantitative measures, as well as with an easy-to-follow graphical representation for detailed qualitative analysis. In the following, we first discuss existing approaches to the classification and visualization of movement sequences that are important for understanding Web navigation. Second, we discuss requirements for the visualization of individual navigation graphs and then present the approach taken with the tool STRATDYN. Third, we show that individualdifferences in the ability to selectively focus attention when navigating the Web can be analyzed with the help of the qualitative and quantitativedata generated by STRATDYN. Finally, implications for further research in this area and the continuing development of the approach presented are discussed