Similar data search device, similar data search method, and recording medium

A method comprising:

• by using a computer device,
• selecting, by using a plurality of inverted indexes that are used when searching for, based on similarity between sets, search target data as a set similar to search condition data as a set and that are each enabled for a range of similarity threshold for determining that sets are similar, wherein for at least one inverted index, a part or whole of the threshold range where the inverted index is enabled is not included in the threshold range where at least one other inverted index is enabled,
• inverted indexes for search from among the plurality of inverted indexes, based on the similarity threshold specified upon search and the threshold range where each of the inverted indexes is enabled;
• and
• searching for the search target data similar to the search condition data by using the inverted indexes for search.

A program causing a computer device to execute:

• inverted index selection processing of selecting,
• by using a plurality of inverted indexes that are used when searching for, based on similarity between sets, search target data as a set similar to search condition data as a set and that are each enabled for a range of similarity threshold for determining that sets are similar, wherein for at least one inverted index, a part or whole of the threshold range where the inverted index is enabled is not included in the threshold range where at least one other inverted index is enabled,
• an inverted index for search from among the plurality of inverted indexes, based on the similarity threshold specified upon search and the threshold range where each of the inverted indexes is enabled;
• and
• data search processing of searching for the search target data similar to the search condition data by using the inverted indexes for search.