tailieunhanh - Báo cáo khoa học: "Exploration of Term Dependence in Sentence Retrieval"

This paper focuses on the exploration of term dependence in the application of sentence retrieval. The adjacent terms appearing in query are assumed to be related with each other. These assumed dependences among query terms will be further validated for each sentence and sentences, which present strong syntactic relationship among query terms, are considered more relevant. Experimental results have fully demonstrated the promising of the proposed models in improving sentence retrieval effectiveness. . | Exploration of Term Dependence in Sentence Retrieval Keke Cai Jiajun Bu Chun Chen Kangmiao Liu College of Computer Science Zhejiang University Hangzhou 310027 China caikeke bjj chenc lkm @ Abstract This paper focuses on the exploration of term dependence in the application of sentence retrieval. The adjacent terms appearing in query are assumed to be related with each other. These assumed dependences among query terms will be further validated for each sentence and sentences which present strong syntactic relationship among query terms are considered more relevant. Experimental results have fully demonstrated the promising of the proposed models in improving sentence retrieval effectiveness. 1 Introduction Sentence retrieval is to retrieve sentences in response to certain requirements. It has been widely applied in many tasks such as passage retrieval Salton et al 1994 document summarization Daumé and Marcu 2006 question answering Li 2003 and novelty detection Li and Croft 2005 . A lot of different approaches have been proposed for this service but most of them are based on term matching. Compared with document sentence always consists of fewer terms. Limited information contained in sentence makes it quite difficult to implement such term based matching approaches. Term dependence which means that the presence or absence of one set of terms provides information about the probabilities of the presence or absence of another set of terms has been widely accepted in recent studies of information retrieval. Taking into account the limited infor 97 mation about term distribution in sentence the necessary of incorporating term dependence into sentence retrieval is clear. Two kinds of dependence can be considered in the service of sentence retrieval. The first one occurs among query or sentence terms and another one occurs between query and sentence terms. This paper mainly focuses on the first kind of dependence and correspondingly proposes a new sentence .