Abstract
Recently the development of computers and networks makes amount of information huge. It is very difficult to find necessary information in the huge information. The existing retrieval system uses not the meaning of input words but the notation of them. Therefore, different words bring a defferent result of retreieval even if they have the same meaning. A user of the system has to consider the input words to search the necessary information. This paper proposes the quantification technique of the semantic distance between documents based on relevance of the word to realize the search that captured the meaning of the document. Concretely the related degree between words is calculated by concept-base and the resemblance degree between documents is calculated by Earth Mover’s Distance. Besides this paper proposes method that no existence word on concept-base is defined as a concept based on Web information to expand concept-base automatically. Retrieval experiments using the NTCIR3-WEB in comparison with the other method have shown that our method is effective than other method.
