Parsing Chinese With an Almost-Context-Free Grammar

We describe a novel parsing strategy we are employing for Chinese. We believe progress in Chinese parsing technology has been slowed by the excessive ambiguity that typically arises in pure context-free grammars. This problem has inspired a modified formalism that enhances our ability to write and maintain robust large grammars, by constraining productions with left/right contexts and/or nonterminal functions. Parsing is somewhat more expensive than for pure context-free parsing, but is still efficient by both theoretical and empirical analyses. Encouraging experimental results with our current grammar are described.