A Statistical Constraint Dependency Grammar (CDG) Parser

CDG represents a sentence’s grammatical structure as assignments of dependency relations to functional variables associated with each word in the sentence. In this paper, we describe a statistical CDG (SCDG) parser that performs parsing incrementally and evaluate it on the Wall Street Journal Penn Treebank. Using a tight integration of multiple knowledge sources, together with distance modeling and synergistic dependencies, this parser achieves a parsing accuracy comparable to several state-of-the-art context-free grammar (CFG) based statistical parsers using a dependency-based evaluation metric. Factors contributing to the SCDG parser’s performance are analyzed.