Changes of search terms and tactics while writing a research proposal - A longitudinal case study

The study analyses how students' growing understanding of the topic and search experience were related to their choice of search tactics and terms while preparing a research proposal for a small empirical study. In addition to that, the findings of the study are used to test Vakkari's (2001) theory of task-based IR. The research subjects were 22 students of psychology attending a seminar for preparing the proposal. They made a search for their task in PsychINFO database at the beginning and end of the seminar. Data were collected in several ways. A pre- and post-search interview was conducted in both sessions. The students were asked to think aloud in the sessions. This was recorded as were the transaction logs. The results show that search experience was slightly related to the change of facets. Although the students' vocabulary of the topic grew generating an increased use of specific terms between the sessions, their use of search tactics and operators remained fairly constant. There was no correlation between the terms and tactics used and the total number of useful references found. By comparing these results with the findings of relevant earlier studies the conclusion was drawn that domain knowledge has an impact on searching assuming that users have a sufficient command of the system used. This implies that the tested theory of task-based IR is valid on condition that the searchers are experienced. It is suggested that the theory should be enriched by including search experience in its scope. (C) 2002 Elsevier Science Ltd. All rights reserved.