Complements and Adjuncts in Dependency Grammar Parsing Emulated by a Constrained Context-Free Grammar
Tom B. Y. Lai, Changning Huang · 1998
Generalizing from efforts parsing natural language sentences using the grammar formalism, Dependency Grammar (DO) has been emulated by a context-flee grammar (CFG) constrained by grammatical function annotation. Single-headedness and projectivity are assumed. This approach has the benefit of making general constraint-based context-free grammar parsing facilities available to DG analysis. This paper describes an experimental implementation of this approach using unification to realize grammatical function constraints imposed on a dependency structure backbone emulated by a context-free grammar. Treating complements of a head word using subcategorization lists residing in the head word makes it possible to keep phrase-structure-rule-like mechanisms to the minimum. Adjuncts are treated with a syntactic mechanism that does not reside in the lexicon in this generally lexical approach to grammar.