METHOD, APPARATUS AND COMPUTER PROGRAM FOR INFORMATION RETRIEVAL

A query building module 6 includes a query DB 61 for managing a query vector of a piece of music, which matches a user preference, a similarity calculating unit 62 for calculating a similarity between the query vectors, which are registered in the query DB 61, a query vector integrating unit 63 for integrating a plurality of query vectors similar to each other into one piece of preference information, and a query updating unit 64 for newly registering the integrated new query vector to the query DB 61 and deleting the integrated two similar query vectors from the query DB 61, thereby updating the query DB 61, and builds a query Q in which all of the query vectors having high similarity are integrated and is an aggregation of the query vectors not similar to each other.