THE EPIC STRUGGLE - SUBJECT RETRIEVAL FROM LARGE BIBLIOGRAPHIC DATABASES

Archivists have talked at length about the virtue of contributing records to a national bibliographic utility to provide enhanced access to collections. There has been little discussion, however, of the difficulties of finding materials in such large database environments. This article discusses a retrieval study that focused on collection-level archival records in the OCLC Online Union Catalog, made accessible through the EPIC search system. Data were also collected from the local OPAC at the University of North Carolina-Chapel Hill (UNC-CH) in which UNC-CH-produced OCLC records are loaded. The chief objective was to explore the retrieval environments in which a random sample of USMARC AMC records produced at UNC-Chapel Hill were found-specifically, to obtain a picture of the density of these databases in regard to each subject heading applied and, more generally, for each record. Key questions were (1) how many records would be retrieved for each subject heading attached to each of the records and (2) what was the nature of these subject headings vis-a-vis the number of hits associated with them. Findings show that large retrieval sets are a potential problem with national bibliographic utilities and that the local and national retrieval environments can vary greatly. The need for specificity in indexing is emphasized. This article is based on a paper given at the Society of American Archivists' 1992 annual meeting in Montreal. OCLC supported this research. The author wishes to thank Patricia Haberkern, who did much of the searching.