Domain-Specific Synonym Expansion and Validation for Biomedical Information Retrieval (MultiText Experiments for TREC 2004)

In the domain of biomedical publications, synonyms and homonyms are omnipresent and pose a great challenge for document retrieval systems. For this year's TREC Genomics Ad hoc Retrieval Task, we mainly addressed the problem of dealing with synonyms. We examined the impact of domain-specic knowledge on the eectiv eness of query expansion and analyzed the quality of Google as a source of query expansion terms based on pseudo-relevance feedback. Our results show that automatic acronym expansion, realized by querying the AcroMed database of biomed- ical acronyms, almost always improves the performance of our document retrieval system. Google, on the other hand, produced results that were worse than the other, corpus-based feedback techniques we used as well in our experiments. We believe that the primary reason for Google's bad performance in this task is its highly restricted query language.