The dissertation, "Characterizing World Wide Web Ecologies" was one of the first dissertations dedicated towards empirically understanding the dynamics of the Web and devising smarter algorithms to tame the content, structure, and usage of the Web.

The number of students studying away from their home countries is increasing. These students face various challenges when studying abroad, including meeting their information needs. This study investigated the information needs of international students at the University of Malaya. A questionnaire was designed and distributed to 70 students, of whom 54 (77.1%) responded. It was found the main information needs were related to the university, the faculty, and their programs of study. The students used the library in attempting to meet their information needs, although the frequency of library usage was generally low. The main barriers in seeking information were language related, and unfamiliarity with the library or-ganization and mission. Language proficiency appeared to be a barrier in being able to meet the information needs. Although the majority of the students considered themselves to be computer and Internet literate, but that did not have a relationship on the problems they faced in meeting the information needs.

Artificial Intelligence Lab, Department of MIS, University of Arizona / We describe an attempt to overcome information overload through information visualization â in a particular domain, group memory. A brief review of information visualization is followed by a brief description of our methodology. We . discuss our system, which uses multidimensional scaling MDS to visualize relationships between documents, and which . we tested on 60 subjects, mostly students. We found three important and statistically significant differences between task performance on an MDS-generated display and on a randomly generated display. With some qualifications, we conclude that MDS speeds up and improves the quality of manual classification of documents and that the MDS display agrees with subject perceptions of which documents are similar and should be displayed together.

Artificial Intelligence Lab, Department of MIS, University of Arizona / With the growth of hypertext and multimedia applications that support and encourage browsing it is time to take a penetrating look at browsing behavior. Several dimensions of browsing are examined, to find out: first, what is browsing and what cognitive processes are associated with it; second, is there a browsing strategy, and if so, are there any differences between how subject-area experts and novices browse; and finally, how can this knowledge be applied to improve the design of hypertext systems. Two groups of students, subject-area experts and novices, were studied while browsing a Macintosh H y p e r c a r d application on the subject of The Vietnam War. A protocol analysis technique was used to gather and analyze data. Components of the GOMS model were used to describe the goals, operators, methods, and selection rules observed. Three browsing strategies were identified: 1) search-oriented browse, scanning and reviewing information relevant to a fixed task, 2) reviewbrowse, scanning and reviewing interesting information in the presence of transient browse goals that represent changing tasks, and 3) scan-browse, scanning for interesting information (without review). Most subjects primarily used review-browse interspersed with search-oriented browse. Within this strategy, comparisons between subject-area experts and novices revealed differences in tactics: experts browsed in more depth, seldom used referential links, selected different kinds of topics, and viewed information differently than did novices. Based on these findings, suggestions are made to hypertext developers.

This study investigates how usersâ cognitive and affective characteristics influence the navigational and search behaviors on the Web among experienced Web users. Sixty-seven undergraduate students participated in the study. Two standardized tests and a questionnaire were used to collect information on the participantsâ cognitive style, problem-solving style, and demographics. Factor analysis was performed on the scores from the two standardized tests (Group Embedded Figures Test and Problem Solving Inventory), and extracted two user factors (Focus Control and Emotion Control). The Focus Control factor seemed to influence usersâ navigational behaviors, such as the use of links and back buttons, whereas the Emotion Control factor affected search behaviors including keyword searching, and also search performance measured by precision and recall.

Traditional information-processing accounts of the reasoning process in radiology assume that humans process the details of the input image in order to compute judgments. In these accounts, the development of expertise involves the acquisition of increasingly precise and complex internal problem representations that are based on a normal anatomy prototype. Fuzzy-trace theory predicts that accurate judgments rely on the reasoners ability to ignore irrelevant detail, to retrieve relevant gist memories and to accurately instantiate the image information with respect to the internal representation. Fuzzy-trace theory predicts that the development of expertise involves the ability to access and process less precise and complex internal representations (i.e., gist). The purpose of this study was to examine the internal representations used to make judgments in radiology and to quantify the changes in complexity of the internal representations, as well as the differences in time, accuracy and confidence that might be associated with experience. Thirty-five subjects from general and specialized expertise samples participated. Each subject was presented with 32 chest films including normal films, films with precise disease patterns (mass category) and diffuse disease patterns (interstitial and airspace category) . For each film, the participant made a series of judgments (normal/abnormal; category; specific diagnosis) and then sketched the features that were essential to the judgments.

This is a preprint of an article published in the Journal of the American Society for Information Science and Technology, 53, 145-161. This study examines the problem of the judgment of information quality and cognitive authority by observing people's searching behavior in the Web. Its purpose is to understand the various factors that influence peopleâ s judgment of quality and authority in the Web, and the effects of those judgments on selection behaviors. It was found that the subjects made two distinct kinds of judgment: predictive judgment and evaluative judgment. The factors influencing each judgment of quality and authority were identified in terms of characteristics of information objects, characteristics of sources, knowledge, situation, ranking in search output, and general assumption.

The educational client interface to the ADEPT digital library is envisioned as a â learning spaceâ where digital objects are tightly integrated with instruction to improve the scientific reasoning and geographic thinking skills of undergraduates. Geography faculty, acting in the work-role of instructor, will be the primary agents utilizing this ADEPT interface. The information behavior of academics is well documented in relation to their work roles as researchers, but little has been published on their information behavior in support of instruction. We report findings from our exploratory study on the information practices of geography faculty in this context. Results suggest that the information behavior of academic geographers follows the Leckie dynamic feedback-loop model. A tentative pattern may exist in the intersection of work roles and information sources. Information seeking for instruction may be characterized as passive and formal while information seeking for research may be characterized as active and informal.

Artificial Intelligence Lab, Department of MIS, University of Arizona / Information overload is a critical problem in World Wide Web. Category map developed based on Kohonenâ s selforganizing map (SOM) has been proven to be a promising browsing tool for the Web. The SOM algorithm automatically categorizes a large Internet information space into manageable sub-spaces. It compresses and transforms a complex information space into a two-dimensional graphical representation. Such graphical representation provides a user-friendly interface for users to explore the automatically generated mental model. However, as the amount of information increases, it is expected to increase the size of the category map accordingly in order to accommodate the important concepts in the information space. It results in increasing of visual load of the category map. Large pool of information is packed closely together on a limited size of displaying window, where local details are difficult to be clearly seen. In this paper, we propose the fisheye views and fractal views to support the visualization of category map. Fisheye views are developed based on the distortion approach while fractal views are developed based on the information reduction approach. The purpose of fisheye views are to enlarge the regions of interest and diminish the regions that are further away while maintaining the global structure. On the other hand, fractal views are an approximation mechanism to abstract complex objects and control the amount of information to be displayed. We have developed a prototype system and conducted a user evaluation to investigate the performance of fisheye views and fractal views. The results show that both fisheye views and fractal views significantly increase the effectiveness of visualizing category map. In addition, fractal views are significantly better than fisheye views but the combination of fractal views and fisheye views do not increase the performance compared to each individual technique.

The information-seeking behavior of social science faculty studying the Kurds was assessed using a questionnaire, citation analysis, and follow-up inquiry. Two specific questions were addressed: how these faculty locate relevant government information and what factors influence their seeking behavior and use of such information. Results show that besides using traditional methods for locating relevant government information, social science faculty studying the Kurds use the World Wide Web and electronic mail too for that purpose, suggesting that these faculty are aware of, and utilize, new information technology to support their research. Results also show that the information-seeking behavior of social science faculty studying the Kurds is influenced by factors similar to those influencing other social science faculty. Moreover, results also show that accessing the needed materials is a major information-seeking activity that should be added to David Ellis's behavioral model, and that faculty examined here employ a somewhat more elaborate "differentiating" information-seeking activity than the one described in the model. Some elements of interdisciplinarity of Kurdish studies as a field of research has been discovered, however, further research is required to verify that. Implications on library services and suggestions for future research are presented.