Orientierung und Navigation in komplexen Hypertext-Systemen

Die vorliegende Arbeit beschäftigt sich mit dem Problem der Orientierung und Navigation in komplexen Hypertext-Systemen. Nach der Darstellung der Grundgedanken von Hypertext, soll ausgehend von der Forschung auf dem Gebiet der Orientierung und Navigation des Menschen in seiner natürlichen Umgebung wie Landschaften und Gebäuden und den dort eingesetzten Hilfsmitteln untersucht werden, wie das Zurechtfin-den im virtuellen Raum einer Website mittels geeigneter Unterstützung verbessert werden kann. Dafür werden ausgewählte Hilfsmittel auf ihre Wirksamkeit beim Navigationsprozess in einer Website hin untersucht

«As auto-estradas, os IP’s e os IC’s da internet : por uma condução pedagógica segura»

A presente comunicação tem como principais objectivos promover a discussão acerca das potencialidades educativas dos documentos em formato «hipermédia. Neste contesto é também discutido o problema relacionado com a subcarga cognitiva na navegação digital. È também propósito nesta comunicação apresentarem-se propostas acerca da grelhas de avaliação páginas Web

Implicit Measures of Lostness and Success in Web Navigation

In two studies, we investigated the ability of a variety of structural and temporal measures computed from a web navigation path to predict lostness and task success. The user’s task was to find requested target information on specified websites. The web navigation measures were based on counts of visits to web pages and other statistical properties of the web usage graph (such as compactness, stratum, and similarity to the optimal path). Subjective lostness was best predicted by similarity to the optimal path and time on task. The best overall predictor of success on individual tasks was similarity to the optimal path, but other predictors were sometimes superior depending on the particular web navigation task. These measures can be used to diagnose user navigational problems and to help identify problems in website design

Cost and Benefit of Information Search using Two Different Strategies

Searching for information is one major Internet activities during which information seekers may gain benefit as well as incurred some cost. In general, information seekers seldom employ any search strategy for general browsing to explore information space. On the other hand, in certain situation, they may employ certain search strategy, especially those who engage in a fact-finding activity. The objective of this research is to shed light on how search strategy can be used to gain the maximum benefit of information search activities. It borrows the two-factor theory to group Web design elements into benefit and cost manifested as motivating and hygiene factors. This research employed a laboratory experiment with 235 respondents who were participated on this research voluntarily. Respondents were divided into two groups, namely ‘plan-group’ and ‘unplan-group’. Both groups were given certain tasks related to information search. The experiment was followed by a post experiment survey. The result shows that respondents who were in the ‘plan-group’ perceived less benefit and incurred more cost compared to those in the ‘unplan-group’. The future research is proposed at the end of this manuscript

Adaptive learning systems: Supporting navigation with customized suggestions

The aim of this study was to share the results from an experimental research which investigate the effects of link annotations in an educational hypermedia on students’ navigation. This study was conducted through a post-test only control group design with 67 undergraduate students. The voluntary research participants were randomly assigned into the experimental and control group. The required data were collected through an academic achievement test, the Motivated Strategies for Learning Questionnaire, the Non-Linear Media Disorientation Assessment Tool, a questionnaire about users’ opinions and user logs. The findings showed that the perceived disorientation scores and revisitation rates were significantly lower for the learners who studied in the adaptive environment than those in the non-adaptive environment. It was observed that students’ non-sequential navigation in experimental group increased significantly and they followed the system's advices.

Effects of hyperlinks on navigation in virtual environments

Hyperlinks introduce discontinuities of movement to 3-D virtual environments (VEs). Nine independent attributes of hyperlinks are defined and their likely effects on navigation in VEs are discussed. Four experiments are described in which participants repeatedly navigated VEs that were either conventional (i.e. obeyed the laws of Euclidean space), or contained hyperlinks. Participants learned spatial knowledge slowly in both types of environment, echoing the findings of previous studies that used conventional VEs. The detrimental effects on participants' spatial knowledge of using hyperlinks for movement were reduced when a time-delay was introduced, but participants still developed less accurate knowledge than they did in the conventional VEs. Visual continuity had a greater influence on participants' rate of learning than continuity of movement, and participants were able to exploit hyperlinks that connected together disparate regions of a VE to reduce travel time