Introduction to Data-Oriented Parsing

We present HPSG–DOP, a method for automatically extracting a Stochas-tic Lexicalized Tree Grammar (SLTG) from a HPSG source grammar and a given corpus. 1 Processing of a SLTG is performed by a specialized fast parser. The approach has been tested on a large English grammar and has been shown to achieve additional performance increase compared to parsing with a highly tuned HPSG parser. Our approach is simple and transparent. The extracted grammars are declaratively represented and have a high degree of practical applicability. Head Driven Phrase Structure Grammar (HPSG) has proven to be a quite successful formalism for specifying natural language grammars in a highly modular and compact manner (Pollard and Sag 1994) supporting the definition of complex linguistic information and interactions between information on different strata systematically using typed feature constraints. On the other hand, inefficiency in processing such grammars is the major obstacle for using the HPSG formalism in practical NL applications (Makino et al. 1998).