Building a Large-Scale Japanese CFG for Syntactic Parsing
نویسندگان
چکیده
Large-scale grammars are a prerequisite for parsing a great variety of sentences, but it is difficult to build such grammars by hand. Yet, it is possible to derive a context-free grammar(CFG) automatically from an existing large-scale, syntactically annotated corpus. While being seemingly a simple task at first sight, CFGs derived in such a fashion have hardly ever been applied to an existing systems. This is probably due to the great number of possible outputs, i.e. parse results(high ambiguity). In this paper, we analyze some causes of this high ambiguity, and we propose a policy for building a large-scale Japanese CFG for syntactic parsing, capable to decrease ambiguity. We end the paper with an experimental evaluation of the obtained CFG.
منابع مشابه
Evaluation of a Japanese CFG Derived from a Syntactically Annotated Corpus with Respect to Dependency Measures
Parsing is one of the important processes for natural language processing and, in general, a large-scale CFG is used to parse a wide variety of sentences. For many languages, a CFG is derived from a large-scale syntactically annotated corpus, and many parsing algorithms using CFGs have been proposed. However, we could not apply them to Japanese since a Japanese syntactically annotated corpus ha...
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