| 摘要 |
PROBLEM TO BE SOLVED: To enable a user to obtain desired retrieval results by enlarging a range of keywords matched with the retrieval results.SOLUTION: Click logs of second data retrieval is retrieved with a keyword of which the number of hits of retrieval results or the number of selecting operations of the retrieval results is zero in first data retrieval. Feature words corresponding to retrieval targets of which the click rates are equal to or higher than a predetermined rate among the retrieval results are estimated as suitable other keywords. Thus, with respect to the keyword of which the number of hits or the number of selecting operations is zero, on the basis of the click logs of the data retrieval in different classes, the feature words of the retrieval targets which are selected many in the case where the keyword is retrieved in the second data retrieval in different target fields or storage data, can be estimated as the suitable other keywords. Therefore, when the keyword of which the number of hits or the number of selecting operations has been zero is designated in the first data retrieval, a range of keywords matched with retrieval results is enlarged so as to enables the user to obtain the desired retrieval results in the future. |
