Katsuhiko Toyama

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When acquiring synonyms from large corpora, it is important to deal not only with such surface information as the context of the words but also their latent semantics. This paper describes how to utilize a latent semantic model PLSI to acquire synonyms automatically from large corpora. PLSI has been shown to achieve a better performance than conventional(More)
Various methods have been proposed for automatic synonym acquisition, as synonyms are one of the most fundamental lexical knowledge. Whereas many methods are based on contextual clues of words, little attention has been paid to what kind of categories of contex-tual information are useful for the purpose. This study has experimentally investigated the(More)
This paper describes Sync/Trans, an incremental spoken language translation system. The system has been being developed for ef-ciently translating a spontaneous speech dialogue between an English speaker and a Japanese speaker. Its purpose being to behave as a simultaneous interpreter, the system produces the target output synchronously with the source(More)
This paper proposes an ad-hoc network system based on mobile agents. We regard some special mobile agent as an implementation of the network protocol. Mobile agents can move over the network while being carried by protocol agents. Implementation of the protocols by the mobile agents enables the dynamic extension of the network. We introduce agent(More)
Distributional similarity is a widely used concept to capture the semantic relatedness of words in various NLP tasks. However, accurate similarity calculation requires a large number of contexts, which leads to impractically high computational complexity. To alleviate the problem, we have investigated the effectiveness of automatic context selection by(More)
The distance or similarity metric plays an important role in many natural language processing (NLP) tasks. Previous studies have demonstrated the effectiveness of a number of metrics such as the Jaccard coefficient, especially in synonym acquisition. While the existing metrics perform quite well, to further improve performance , we propose the use of a(More)
This paper describes a database consisting of speech and language, which w e are currently constructing for the purpose of the research on machine interpretation. The database contains bilingual data of lectures and dialogues. We h a v e collected the speech of about 72 hours in total and transcribed it into the text manually. W e have investigated the(More)
SUMMARY This paper proposes the incremental dependency parsing method based on the context-free grammar with dependency information. In the proposed method, the reachability, which represents the relation between categories , is used. In parallel to the inputting of sentence, the dependency, which is the relation between the modifying word and the modified(More)