OPAC-Erweiterung durch automatische Indexierung : Eine empirische Untersuchung mit Daten aus dem Österreichischen Verbundkatalog

摘要

In the 1990s the German MILOS projects examined the suitability of an automatic linguistic indexing technique for library OPACs. Following this approach, an empirical investigation was conducted that aimed at assessing and evaluating the use of automatic indexing for the OPACs of the Austrian Library Network. As most users prefer to do their OPAC searches in the basic index the study focused on the effects of enriching this index with automatically generated terms. For this purpose an Aleph 500 OPAC consisting of a representative random sample of records drawn from the Austrian Union Catalogue was used for searching 100 queries in the basic index before and after adding the new index terms. The results include an increase of relevant hits at only moderately lower precision, the reduction of zero-hit results and insights into the role of existing subject headings.