| This dissertation examines the current issues, research trends and possible solutions to the problem of visualizing large information spaces. We propose a hypermedia database visualization model as part of the answer to this problem. We take advantage of evidence which shows that ecologically well designed virtual 3D environments can reduce the cognitive load of processing large information sets and aid with navigation and information finding; to build a hypermedia database visualization system. We develop a Systems Architecture as a Client/Server system in which the Server side has the following components: a Database Server (DS), a Communications Manager CM), an Information Profiler and Landscaper (IPL), a Query Translator (QT), Session Cache(s) (SC), a Collaboration Server (CS) (This was not implemented) and a Graphics Object Library (GOL). An HDV Client communicates with the HDV system via a network. When a user logs on to the HDV system via an HDV Client they see a 3D interface to the HDV system. The user can then navigate, browse and issue queries to the Server which returns results displayed in a 3D Scene.; We design the Systems Interface for the HDV System, based on the Hypermedia Database Model and Systems Architecture described above. On the basis of design considerations we studied, we develop five different Systems Interface variants namely: Ecological, 2D Web, Non-Ecological, Relevance and Connectedness designs. We experimentally evaluate the five HDV system variants in four experiments. Hypotheses are put forward for each of the experiments; the null hypothesis being that there is no difference between the five systems. These hypotheses are tested using a set of tasks, which participants carry out on the experimental system.; Based on statistical analysis, the connectedness design turned out the best. It is a powerful feature for aiding the user in navigation and information finding in Hypermedia Database Visualization Systems. Audio and Animation features implemented in the Ecological system while useful in aiding the user with navigation and information finding, do not have repeat benefits once a user knows how to navigate the system. They subsequently serve as distractions. (Abstract shortened by UMI.)... |
