DEVICE AND METHOD FOR RETRIEVING SIMILAR DOCUMENT BY STRUCTURE SPECIFICATION

摘要

PROBLEM TO BE SOLVED: To add the specification of an object structure to be retrieved to retrieval conditions and to improve the retrieval precision when a document which is similar to a seed document (document specified as a retrieval condition) is retrieved. SOLUTION: A retrieval condition expression analyzing program 130 receives the specification of a seed document and the input of an object structure to be retrieved as retrieval conditions. A featured character string extracting program 150 extracts a featured character string from the text of the specified seed document. A retrieval object structure ID acquiring program 151 converts the specified structure into its ID. A similarity calculating program 152 performs retrieval from an appearance frequency file 181 to acquire the appearance frequency of a document whose structure ID matches the featured character string and calculates the similarity of the similar document based upon the seed document. A retrieval result output program 132 displays the identifier and similarity of the similar document as the retrieval result.