Feature-based grammar

This chapter considers some of the basic ideas about language and linguistic analysis that define the family of feature-based grammars. Underlying the complex constraint languages and representations that give this family its characteristic ‘look and feel’ are a number of relatively straightforward claims and hypotheses. Foremost among these is the idea that many of the distinctive properties within a grammatical system can be described in terms of (morpho-) syntactic features. A related claim is that many grammatical dependencies – both local and non-local – can be regulated by strategies that determine the compatibility of the feature information associated with grammatical dependents. A third claim is more formal than substantive and is formulated in somewhat dierent ways in dierent approaches. But the shared intuition is that the strategies that determine compability do not merely compare or ‘check’ grammatical dependents to see if they have conflicting values for common features. Instead, the compatibility of two or more dependents is determined ‘constructively’, by invoking principles that are only satisfied if there is an object that in some way combines the feature information associated with each of the dependents. These substantive claims interact with auxiliary assumptions and implementation choices in ways that define the dierent variants of feature-based frameworks. Specific inventories of features and values dier considerably across approaches, as do basic terminological and interpretive conventions. Traditional morphosyntactic properties, such as tense, aspect, agreement and case, are usually represented by syntactic features, though there is less of a consensus regarding the treatment of phenomena such as voice alternations or word order variation. The organization of features within a syntactic analysis also varies a great deal from one approach to the next, and tends to reflect general properties of a model, especially assumptions about the relation between features and constituent structure. In these respects, feature-based approaches can appear to comprise a family of approaches separated by a common metalanguage. There is, however, more of a consensus regarding the formal strategies that determine feature compatibilitywithin contemporary feature-based approaches.