Paper: Cluster-Based Query Expansion for Statistical Question Answering

ACL ID I08-1056
Title Cluster-Based Query Expansion for Statistical Question Answering
Venue International Joint Conference on Natural Language Processing
Session Main Conference
Year 2008

Document retrieval is a critical component of question answering (QA), yet little work has been done towards statistical modeling of queries and towards automatic generation of high quality query content for QA. This paper introduces a new, cluster-based query expansion method that learns queries known to be successful when applied to similar questions. We show that cluster-based ex- pansion improves the retrieval performance of a statistical question answering system when used in addition to existing query ex- pansion methods. This paper presents exper- iments with several feature selection meth- ods used individually and in combination. We show that documents retrieved using the cluster-based approach are inherently differ- ent than documents retrieved using existing methods and provide ...