Hedge trimming and the resurrection of the controlled vocabulary in online searching

Abstract

The traditional role of the controlled vocabulary has been to bring together items scattered by a multiplicity of natural language terms. Therefore, it was considered a recall device. The file structure of current online structure systems now leads to the use of such vocabularies as a precision device. Because of the levels of specificity in the controlled vocabulary, the search for broader concepts means several terms may be ncessary. In this case, the file structure of the retrieval systems requires that for efficient searching the entry points be analyzed and minimized. Complete, rather than partial, entry of controlled terms appears to be inefficient.