Angela Brunstein

Interaction between text structure representation and situation model in hypertext reading.

Hypertext research results suggest that building a correct representation of the hypertext structure enables users to navigate effectively within the text. Therefore, text comprehension processes involved in hypertext reading should be investigated. In an experimental study, we differentiated the text structure from the dimensions of a postulated coherent situation model in order to compare them. Three electronic text versions, varying in navigational facility, and text structure visualization were compared with respect to orientation, navigation, eye movements, mental representation of text structure and content (situation model). Results demonstrate that when text structure visualization was unavailable, a reorganization of readers’ representations of the text structure towards their situation model took place. Navigation within the text particularly affected mental representation of text structure and content.

Training for emergencies.

BACKGROUND Disaster triage embodies all key features of dynamic decision making. Multiple decisions have to be made under time pressure and workload. Situations are often unpredictable requiring trainees to apply learned routines to novel conditions. Up to this point, psychologic theories of learning can provide only little support on how to train disaster responders for these challenging situations. METHODS We summarize and illustrate several examples of dynamic decision-making research using simulations and microworlds as a starting point for a new theory of learning and skill acquisition in disaster triage. We describe MEDIC, a microworld in the context of medical diagnosis, and other simple tasks designed to gather peoples understanding of accumulation, a basic component of dynamic tasks. RESULTS Using a microworld called MEDIC, we demonstrate the difficulties of learning to be effective at medical decision making and present a set of theoretical constructs that help to explain those difficulties. Implications for how to overcome them are also discussed. On the basis of this kind of research and our instance-based learning theory, we develop principles for the design of effective disaster training and for building a theoretical framework that can systematically predict how to best train for successful performance in disaster situations. Finally, we also demonstrate the difficulty of understanding dynamic systems; educated adults with medical expertise have trouble understanding even simple dynamic medical problems. CONCLUSIONS Dynamic decision-making research can be used as a theoretical and empirical reference for advancing pediatric triage training to prepare trainees for disaster triage. Recommendations for effective learning derived from dynamic decision-making research are presented.

Einfluss des Bearbeitungsziels auf die Strategiewahl beim hypertextgestützten Lernen

Zusammenfassung: In der Problemloseforschung und Hypertextforschung zeigte sich wiederholt, dass Lerner mit unspezifischem bzw. spezifischem Bearbeitungsziel unterschiedlich vom bearbeiteten Material profitieren. Leser mit unspezifischem Ziel erwerben eher breites allgemeines und transferierbares Wissen, wahrend sich Sucher, die nach spezifischen Details im Material suchten, eher grundliches aber nicht transferierbares Detailwissen aneignen. Die vorliegende Studie untersuchte, welche Bearbeitungsstrategien diesen Befunden zugrunde liegen. 40 Studenten bearbeiteten zwei Kapitel zur englischen Grammatik mit unspezifischem Leseziel bzw. spezifischem Suchziel, wobei sie Regeln, Beispiele und Ubungen bearbeiteten. Passend zu den in der Literatur berichteten Unterschieden im erworbenen Wissen zeigten die Logfiles der Lernsitzungen, dass Leser zwar mehr Seiten besuchten als Sucher, sich allerdings auch kurzer dort aufhielten. Zusatzlich investierten beide Gruppen mehr Zeit in das Lesen der Regeln als in das Bearbeiten der Ubungen. Navigationsstile und Verarbeitungszeiten werden in Zusammenhang mit den Lernergebnissen vor dem Hintergrund der Problemlose- und Hypertextforschung diskutiert. Schlusselworter: Bearbeitungsziele, Hypertext, Lernen, Lernstrategien Summary: The specifity of learners’ processing goal is an essential factor in learning and problem solving with educational hypertext. There is a reported trade-off between steady navigation and higher comprehension of general knowledge shown by learners reading the hypertext without specific tasks and more efficient navigation and understanding of details shown by learners searching for specific information in the hypertext. This study investigated processing strategies for processing an educational hypertext. 40 students processed two chapters of the Chemnitz Internet Grammar either without specific tasks or for answering specific questions. Corresponding to the different learning outcomes learners differed significantly in processing strategies in respect to processing times, visited pages and navigational pattern. Learners without specific tasks visited more pages for shorter times than learners answering specific questions. Moreover, both groups preferred processing rules pages instead of processing examples or exercises.

Helps and Hints for Learning with Web Based Learning Systems: The Role of Instructions

This study investigated the role of specific and unspecific tasks for learning declarative knowledge and skills with a web based learning system. Results show that learners with specific tasks where better for both types of learning. Nevertheless, not all kinds of learning outcomes were equally influenced by instruction. Therefore, instructions should be selected carefully in correspondence with desired learning goals.

The Chemnitz LogAnalyzer: A tool for analyzing data from hypertext navigation research

Computer-based studies usually produce log files as raw data. These data cannot be analyzed adequately with conventional statistical software. The Chemnitz LogAnalyzer provides tools for quick and comfortable visualization and analyses of hypertext navigation behavior by individual users and for aggregated data. In addition, it supports analogous analyses of questionnaire data and reanalysis with respect to several predefined orders of nodes of the same hypertext. As an illustration of how to use the Chemnitz LogAnalyzer, we give an account of one study on learning with hypertext. Participants either searched for specific details or read a hypertext document to familiarize themselves with its content. The tool helped identify navigation strategies affected by these two processing goals and provided comparisons, for example, of processing times and visited sites. Altogether, the Chemnitz LogAnalyzer fills the gap between log files as raw data of Web-based studies and conventional statistical software.

Learning Grammar with Adaptive Hypertexts: Reading or Searching?

Using adaptive hypertext as a learning tool, the present study addresses the question of the effects of different processing goals, especially the goal of general reading a hypertext as opposed to the goal of searching for specific information, on learning content and skills at English grammar. Twenty students with German as mother tongue processed the present continuous chapter of the Chemnitz InternetGrammar. It has been shown that readers answer a higher amount of questions about details and, more importantly, they answer them in more detail than searchers. Nevertheless, searchers tend to produce more elaborated answers to complex questions than readers. Both groups performed better on skill tests after the session, showing no effect of the performed task. Based on this experimental evidence, the requirements on adaptive learning tools are discussed.

DEWEX: A system for designing and conducting Web-based experiments

DEWEX is a server-based environment for developing Web-based experiments. It provides many features for creating and running complex experimental designs on a local server. It is freeware and allows for both using default features, for which only text input is necessary, and easy configurations that can be set up by the experimenter. The tool also provides log files on the local server that can be interpreted and analyzed very easily. As an illustration of how DEWEX can be used, a recent study is presented that demonstrates the system’s most important features. This study investigated learning from multiple hypertext sources and shows the influences of task, source of information, and hypertext presentation format on the construction of mental representations of a hypertext about a historical event.