tailieunhanh - Báo cáo khoa học: "Alternative Phrases and Natural Language Information Retrieval"

This paper presents a formal analysis for a large class of words called alternative markers, which includes other(than), such(as), and besides. These words appear frequently enough in dialog to warrant serious attention, yet present natural language search engines perform poorly on queries containing them. I show that the performance of a search engine can be improved dramatically by incorporating an approximation of the formal analysis that is compatible with the search engine’s operational semantics. . | Alternative Phrases and Natural Language Information Retrieval Gann Bierner Division of Informatics University of Edinburgh gbierner@ Abstract This paper presents a formal analysis for a large class of words called alternative markers which includes other than such as and besides. These words appear frequently enough in dialog to warrant serious attention yet present natural language search engines perform poorly on queries containing them. I show that the performance of a search engine can be improved dramatically by incorporating an approximation of the formal analysis that is compatible with the search engine s operational semantics. The value of this approach is that as the operational semantics of natural language applications improve even larger improvements are possible. 1 Introduction Consider the following examples discovered in a corpus of queries submitted to the Electric Knowledge search engine12 the successor of the On Point natural language search system described in Cooper 1997 . Each consists of a query a response not shown and then a follow-up query. 1 What is the drinking age in Afghanistan What is the drinking age in other countries 2 Where can I find web browsers for download Where can I find other web browsers than Netscape for download 3 Where can I find a list of all the shoe manufacturers in the world Where can I find shoes made by Buffalino such as the Bushwackers 4 Where are online auctions indexed Are there other auction search engines besides BidFind 1 formerly known as The Electric Monk 2 http In each case particular words are used to constrain the space of appropriate answers . such as other than and besides. I call these words and others like them alternative markers and alternative markers along with their syntactic argument . other countries I call alternative phrases. Alternative phrases that are closely bound to the noun phrase to which they refer like those above I call connected .