| 摘要 |
PROBLEM TO BE SOLVED: To exactly and easily grasp information requested by a lot of users by summing up related degrees calculated about plural retrieval users. SOLUTION: A retrieval time/retrieval expression extracting part 10 by users extracts retrieval time and a retrieval expression for every retrieval user from data in retrieval performed during a prescribed period in the past. A minimum time difference calculating part 20 calculates the minimum time difference of minimum value among time differences between time, in which one of plural extracted retrieval expression is used, and time, in which the other one of plural extracted retrieval expressions is used, for every retrieval user. Based on the minimum time difference for the prescribed retrieval user, a related degree calculating/summing-up part 30 calculates the degree of relation between one retrieval expression corresponding to the minimum time difference and the other retrieval expression for every prescribed retrieval user and sums up the related degrees calculated concerning plural retrieval users. |
