Web-Scale Features for Full-Scale Parsing
Mohit Bansal, Dan Klein · 2011
Counts from large corpora (like the web) can be powerful syntactic cues. Past work has used web counts to help resolve isolated ambiguities, such as binary noun-verb PP attachments and noun compound bracketings. In this work, we first present a method for generating web count features that address the full range of syntactic attachments. These features encode both surface evidence of lexical affinities as well as paraphrase-based cues to syntactic structure. We then integrate our features into full-scale dependency and constituent parsers. We show relative error reductions of 7.0 % over the second-order dependency parser of McDonald and Pereira (2006), 9.2 % over the constituent parser of Petrov et al. (2006), and 3.4 % over a non-local constituent reranker. 1