Qualia Structure and the Compositional Interpretation of Compounds

Qualia Structure and the Compositional Interpretation of Compounds Michael Johnston§ and Federica Busat Research Lab for Linguistics and Computation, Computer Science Department, Volen Center for Complex Systems, Brandeis University, Waltham, MA 02254 §johnston@cs .brandeis. edu tfederica©cs, brandeis, edu Abstract The analysis of nominal compound constructions has proven to be a recalcitrant problem for linguistic semantics and poses serious challenges for natural language processing systems. We argue for a compositional treatment of compound constructions which limits the need for listing of compounds in the lexicon. We argue that the development of a practical model of compound interpretation crucially depends on issues of lexicon design. The Generative Lexicon (Pustejovsky 1995) provides us with a model of the lexicon which couples sufficiently expressive lexical semantic representations with mechanisms which capture the relationship between those representations and their syntactic expression. In our approach, the qualia structures of the nouns in a compound provide relational structure enabling compositional interpretation of the modification of the head noun by the modifying noun. This brings compound interpretation under the same rubric as other forms of composition in natural language, including argument selection, adjectival modification, and type coercion (Pustejovsky (1991,1995), Bouillon 1995). We examine data from both English and Italian and develop analyses for both languages which use phrase structure schemata to account for the connections between lexical semantic representation and syntactic expression. In addition to applications in natural language understanding, machine translation, and generation, the model of compound interpretation developed here can be applied to multi-lingual information extraction tasks. 77 1 Introduction The analysis of nominal compound constructions has proven to be a recalcitrant problem for linguis- tic semantics (Bergsten 1911, Jespersen 1942, Marchand 1970, Lees 1970, Downing 1977, Levi 1978, Warren 1987), and their analysis has presented a serious challenge for natural language processing systems (Finin 1980, McDonald 1982, Isabelle 1984, Alshawi 1987, Hobbs et al 1993, Bouillon et al 1992, Jones 1995, Johnston, Boguraev, and Pustejovsky 1995). In this paper, we argue that composition in compound constructions involves specification of the arguments of predicate struc- tures within the qualia structure of the head noun. In essence, the qualia structure provides the 'glue' which links together the semantic contributions of modifying nouns and the head noun in the compound. This approach has significant advantages over approaches which introduce abstract relations to describe the form of modification involved (Levi 1978, Jones 1995), in that it assimilates the composition of complex nominals to other compositional processes of natural language. The predicates in the qualia are not there just to account for compounds but also to account for a wide variety of forms of composition and interpretation including argument selection, adjectival modi- fication, and type coercion (Pustejovsky (1991,1995), Bouillon 1995). In order to account for the availability of compounds and other complex nominals we utilize phrase structure schemata which capture the different ways in which head nouns and modifying nouns can compose. We develop and illustrate our approach using data from English and Italian. Consider the correspondences below in (1). …

Content truncated to 500 words