Japanese Case Frame Construction by Coupling the Verb and its Closest Case Component

This paper describes a method to construct a case frame dictionary automatically from a raw corpus. The main problem is how to handle the diversity of verb usages. We collect predicate-argument examples, which are distinguished by the verb and its closest case component in order to deal with verb usages, from parsed results of a corpus. Since these couples multiply to millions of combinations, it is difficult to make a wide-coverage case frame dictionary from a small corpus like an analyzed corpus. We, however, use a raw corpus, so that this problem can be addressed. Furthermore, we cluster and merge predicate-argument examples which does not have different usages but belong to different case frames because of different closest case components. We also report on an experimental result of case structure analysis using the constructed case frame dictionary.