Korean Parsing Based on the Applicative Combinatory Categorial Grammar

Korean Parsing Based on the Applicative Combinatory Categorial Grammar* Juyeon Kang, Jean-Pierre Desclés LaLIC Laboratory, Paris-Sorbonne University 28, Rue Serpente, 75006, Paris, France kjuyeon79@yahoo.fr, jean-pierre.descles@paris4.sorbonne.fr Abstract. The Applicative Combinatory Categorial Grammar (ACCG) is a new approach to Categorial Grammars by using exclusively the Combinatory Logic. This extended categorial grammar that was originally developed by J.-P. Desclés and I. Biskri, allows us to tackle the problem of the Korean language parsing in which there exist many difficulties from a computational point of view. In this paper, we handle in particular some parsing problems in Korean such as the problem of case, the free word order phenomenon, the coordination structure and the long distance scrambling in the coordination structure. We will show throughout this work some new and robust solutions for the Korean parsing in the ACCG formalism by introducing combinators such as B, C*, Φ of Combinatory Logic developed by H.-B. Curry and R. Feys. Keywords: Korean, Parsing, Categorial Grammar, Combinatory Logic, ACCG. 1. Introduction In this paper, we propose a new approach to Categorial Grammars by introducing Curry’s Combinatory Logic (Curry & Feys 1958) in order to improve the parsing of Korean texts from a computational point of view. Since the introduction of simple Categorial Grammars, different propositions were made to improve this formalism by adopting applicative languages such as the calculus of syntactic types proposed by J. Lambek (1961), the lambda-calculus proposed by A. Church, the combinatory logic created by the mathematician H.-B. Curry (1958), some attempts by the logician W. V. O. Quine, etc. These works are based on the mechanism of the application of an operator to an operand. Combinatory logic and lambda-calculus were applied to the analysis of grammatical and lexical meaning in natural languages by S. K. Shaumyan (1987) with his model of the Universal Applicational Grammar using Curry’s combinatory logic, which extends the simple Categorial Grammars: this model is easily implementable on computational tools using functional programming languages such as CAML, HASKELL and SCHEME. In the 80’s, important extensions were given by R. Montague, M. Moortgat (1988), J. Lambek and M. Steedman (1989). Combinatory Categorial Grammar (CCG) developed by Steedman (1989, 2001) was most often quoted and studied for the analysis of Korean sentences. There exist several studies on Korean parsing based on the Categorial Grammar formalism. For example, the Korean Combinatory Categorial Grammar (KCCG) was developed by (Cha 2001 and Cha & Lee 2002) by extending the CCG of Steedman for the Korean parsing. The KCCG, having a purely computational approach, shows the ability to handle important linguistic phenomena of the Korean such as coordination, long distance scrambling, free word Copyright 2008 by Juyeon Kang, Jean-Pierre Desclés 215 22nd Pacific Asia Conference on Language, Information and Computation, pages 215–224 order, etc. Cho and Park (2000) tried also to improve the complexity in the coordination, and Lee and Park (2003) proposed a morphological analysis of the irregular conjugation of Korean in order to conceive a morphological parser. The studies presented above and most of …

Content truncated to 500 words