Parsing Spoken Language Using Combinatory Grammars

Combinatory Grammars are a generalization of Categorial Grammars to include operations on function categories corresponding to the combinators of Combinatory Logic, such as functional composition and type raising. The introduction of such operations is motivated by the need to provide an explanatory account of coordination and unbounded dependency. However, the associativity of functional composition tends to engender an equivalence class of possible derivations for each derivation permitted by more traditional grammars. While all derivations in each class by definition deliver the same function-argument relations in their interpretation, the proliferation of structural analyses presents obvious problems for parsing within this framework and the related approaches based on the Lambek calculus (cf. Moortgat, 1988).