TREC 2005 genomics track experiments at IBM watson

Abstract

This paper describes our experiments in the TREC 2005 Genomics Track. For the ad-hoc retrieval task, we study synonym-based query expan-sion, as well as the effectiveness of a new pseudo-relevance feedback method which is derived from our recent work on semi-supervised learning. For the categorization task, we study vari-ous methods for estimating conditional class probability and determining the optimal threshold parameter — essen-tial for obtaining high performance re-sults for this task.