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Title: Left-corner unification-based natural language processing

Conference ·
OSTI ID:430780
;  [1]
  1. DePaul Univ., Chicago, IL (United States)

In this paper, we present an efficient algorithm for parsing natural language using unification grammars. The algorithm is an extension of left-corner parsing, a bottom-up algorithm which utilizes top-down expectations. The extension exploits unification grammar`s uniform representation of syntactic, semantic, and domain knowledge, by incorporating all types of grammatical knowledge into parser expectations. In particular, we extend the notion of the reachability table, which provides information as to whether or not a top-down expectation can be realized by a potential subconstituent, by including all types of grammatical information in table entries, rather than just phrase structure information. While our algorithm`s worst-case computational complexity is no better than that of many other algorithms, we present empirical testing in which average-case linear time performance is achieved. Our testing indicates this to be much improved average-case performance over previous leftcomer techniques.

OSTI ID:
430780
Report Number(s):
CONF-960876-; TRN: 96:006521-0155
Resource Relation:
Conference: 13. National conference on artifical intelligence and the 8. Innovative applications of artificial intelligence conference, Portland, OR (United States), 4-8 Aug 1996; Other Information: PBD: 1996; Related Information: Is Part Of Proceedings of the thirteenth national conference on artificial intelligence and the eighth innovative applications of artificial intelligence conference. Volume 1 and 2; PB: 1626 p.
Country of Publication:
United States
Language:
English