tailieunhanh - Báo cáo khoa học: "Discovering the Lexical Features of a Language"

the lexical features of a language. The work is based upon the hypothesis that whenever two words are semantically dissimilar, this difference will manifest itself in the syntax via lexical distribution (in a sense, playing out the notion of distributional analysis [Harris 51]). Most, if not all, features have a semantic basis. For instance, there is a clear semantic difference between most count and mass nouns. But while meaning specifies the core of a word class, it does not specify precisely what can and cannot be a member of a class. For instance, furniture is a mass noun in. | Discovering the Lexical Features of a Language Eric Brill Department of Computer and Information Science University of Pennsylvania Philadelphia PA 19104 email brill@ 1 Introduction This paper examines the possibility of automatically discovering the lexical features of a language. There is strong evidence that the set of possible lexical features which can be used in a language is unbounded and thus not innate. Lakolf Lakoff 87 describes a language in which the feature woman-or-fire-or-dangerous-thing exists. This feature is based upon ancient folklore of the society in which it is used. If the set of possible lexical features is indeed unbounded then it cannot be part of the innate Universal Grammar and must be learned. Even if the set is not unbounded the child is still left with the challenging task of determining which features are used in her language. If a child does not know a priori what lexical features are used in her language there are two sources for acquiring this information semantic and syntactic cues. A learner using semantic cues could recognize that words often refer to objects actions and properties and from this deduce the lexical features noun verb and adjective. Pinker Pinker 89 proposes that a combination of semantic cues and innate semantic primitives could account for the acquisition of verb features. He believes that the child can discover semantic properties of a verb by noticing the types of actions typically taking place when the verb is uttered. Once these properties are known says Pinker they can be used to reliably predict the distributional behavior of the verb. However Gleitman Gleitman 90 presents evidence that semantic cues are not sufficient for a child to acquire verb features and believes that the use of this semantic information in conjunction with information about the subcategorization properties of the verb may be sufficient for learning verb features. This paper takes Gleitman s suggestion to the .