DeHart, F.E.; Glazier, J.: Computer searching on PRECIS : an exploration of measuring comparative retrieval effectiveness (1984)
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- Abstract
- Designing research on the retrieval effectiveness of computer searches on PRECIS compared with retrieval effectiveness of searches on other types of subject analysis used in computer-based information sources is a complex process. This paper explores the complexity of measuring comparative retrieval effectiveness through a comparison of the subject analysis provided by the PRECIS system for fifty articles with the subject analysis provided for the same articles by three computer-based information sources: ERIC/CIJE, LLBA/Online and PsycINFO. Objectives are: (1) to discover factors that should be taken into account when designing this type of research; and (2) to identify extraneous variables that work against internal validity in research design .
- Theme
- Preserved Context Index System (PRECIS)
