tailieunhanh - Báo cáo khoa học: "Compilation of HPSG to TAG*"

We present an implemented compilation algorithm that translates HPSG into lexicalized feature-based TAG, relating concepts of the two theories. While HPSG has a more elaborated principle-based theory of possible phrase structures, TAG provides the means to represent lexicalized structures more explicitly. Our objectives are met by giving clear definitions that determine the projection of structures from the lexicon, and identify "maximal" projections, auxiliary trees and foot nodes. | Compilation of HPSG to TAG Robert Kasper Dept of Linguistics Ohio State University 222 Oxley Hall Columbus OH 43210 . Bernd Kiefer Klaus Netter Deutsches Forschungszentrum fur Kunstliche Intelligenz GmbH Stuhlsatzenhausweg 3 66123 Saarbrucken Germany kasper ling. ohio-state. edu kiefer I netter dfki. uni-sb. de K. Vijay-Shanker CIS Dept. University of Delaware Newark DE 19716 vij ay cis. udel. edu Abstract We present an implemented compilation algorithm that translates HPSG into lex-icalized feature-based TAG relating concepts of the two theories. While HPSG has a more elaborated principle-based theory of possible phrase structures TAG provides the means to represent lexicalized structures more explicitly. Our objectives are met by giving clear definitions that determine the projection of structures from the lexicon and identify maximal projections auxiliary trees and foot nodes. 1 Introduction Head Driven Phrase Structure Grammar HPSG and Tree Adjoining Grammar TAG are two frameworks which so far have been largely pursued in parallel taking little or no account of each other. In this paper we will describe an algorithm which will compile HPSG grammars obeying certain constraints into TAGs. However we are not only interested in mapping one formalism into another but also in exploring the relationship between concepts employed in the two frameworks. HPSG is a feature-based grammatical framework which is characterized by a modular specification of linguistic generalizations through extensive use of principles and lexicalization of grammatical information. Traditional grammar rules are generalized to schemata providing an abstract definition of grammatical relations such as head-of complement-of subject-of adjunct-of etc. Principles such as the We would like to thank A. Abeillé D. Flickinger A. Joshi T. Kroch o. Rambow I. Sag and H. Uszko-reit for valuable comments and discussions. The research underlying the paper was supported by research grants from the