Language models for genomics information retrieval: UIUC at TREC 2007 Genomics Track

The University of Illinois at Urbana-Champaign (UIUC) participated in TREC 2007 Genomics Track. Our general goal of participation is to apply language modelbased approaches to the genomics retrieval task and study how we may extend the standard language models to accommodate two special needs for this year's genomics retrieval task: (1) gene synonym expansion and (2) conjunctive query interpretation. We also tested user relevance feedback. Preliminary result analysis shows that our synonym expansion method can improve document-level MAP, but generally has little influence on passagelevel and aspect measures, while conjunctive scoring is not as effective as the standard KL-Divergence scoring, even though our pre-TREC experiments on a small set of training data showed otherwise. Relevance feedback appears to help. Further experiments and analysis are needed to draw more definitive conclusions.