A Corpus-based Account of Regular Polysemy: The Case of Context-sensitive Adjectives

A Corpus-based Account of Regular Polysemy: The Case of Context-sensitive Adjectives Maria Lapata∗ Department of Computational Linguistics Saarland University PO Box 15 11 50 66041 Saarbr¨ucken, Germany mlap@coli.uni-sb.de Abstract In this paper we investigate polysemous adjectives whose meaning varies depending on the nouns they modify (e.g., fast). We acquire the meanings of these adjectives from a large corpus and propose a probabilistic model which provides a ranking on the set of possible interpre- tations. We identify lexical semantic information auto- matically by exploiting the consistent correspondences between surface syntactic cues and lexical meaning. We evaluate our results against paraphrase judgments elicited experimentally from humans and show that the model’s ranking of meanings correlates reliably with hu- man intuitions: meanings that are found highly probable by the model are also rated as plausible by the subjects. 1 Introduction Much recent work in lexical semantics has been con- cerned with accounting for regular polysemy, i.e., the regular and predictable sense alternations certain classes of words are subject to. Adjectives, more than other cat- egories, are a striking example of regular polysemy since they are able to take on different meanings depending on their context, viz., the noun or noun class they modify (see Pustejovsky (1995) and the references therein). The adjective fast in (1) receives different interpre- tations when modifying the nouns programmer, plane and scientist. A fast programmer is typically a program- mer who programs quickly, a fast plane is typically a plane that flies quickly, a fast scientist can be a scien- tist who publishes papers quickly, who performs exper- iments quickly, who observes something quickly, who reasons, thinks, or runs quickly. Interestingly, adjectives like fast are ambiguous across and within the nouns they modify. A fast plane is not only a plane that flies quickly, but also a plane that lands, takes off, turns, or travels quickly. Even the more restrictive fast programmer al- lows more than one interpretation. One can easily think of a context where a fast programmer thinks, runs or talks quickly. (1) a. fast programmer b. fast plane c. fast scientist ∗The work reported in this paper was carried out while the author was at the Division of Informatics, University of Edinburgh. (2) a. easy problem b. difficult language c. good cook d. good soup Adjectives like fast have been extensively studied in the lexical semantics literature and their properties have been known at least since Vendler (1968). The meaning of adjective-noun combinations like those in (1) and (2) are usually paraphrased with a verb modified by the adjective in question or its corresponding adverb. For example, an easy problem is “a problem that is easy to solve” or “a problem that one can solve easily”. In order to account for the meaning of these combinations Vendler (1968, 92) points out that “in most cases not one verb, but a fam- ily of verbs is needed”. Vendler further observes that the noun figuring in an adjective-noun combination is usu- ally the subject or object of …

Content truncated to 500 words