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-specific knowledge on the effectiveness 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 biomedical 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.
Stefan Büttcher, Charles L. A. Clarke, Gordon