System and method for indexing documents and retrieving similar document based on link transition count distance calculations

摘要

In an index generating device, a similarity calculating unit calculates access similarities indicating similarities of access histories between documents, based on history information indicating the access histories to the respective documents by users, and a similar document specifying unit specifies a similar document similar to a given document as a retrieval target, based on the access similarities or the like. A retrieval index generating unit generates a retrieval index for the given document as the retrieval target from words appearing in a document set consisting of the similar document and the given document as the retrieval target.