GIRT and the Use of Subject Metadata for Retrieval

The use of domain-specific metadata (subject keywords) is tested for monolingual and bilingual retrieval on the GIRT social science collection. A new technique, Entry Vocabulary Modules, which adds subject keywords selected from the controlled vocabulary to the query, has been tested. As in previous years, we compare our techniques of thesaurus matching and Entry Vocabulary Modules to simple machine translation techniques in bilingual retrieval. A combination of machine translation and thesaurus matching achieves better results, whereas the introduction of Entry Vocabulary Modules has negligent impact on the retrieval results. Retrieval results for the German and English GIRT collection for monolingual as well as bilingual retrieval (with English and German as query languages) will be represented.