RELATIVE DOCUMENT RETRIEVAL DEVICE AND RECORD MEDIUM WHERE RELATIVE DOCUMENT RETRIEVING PROGRAM IS RECORDED

摘要

PROBLEM TO BE SOLVED: To enable relative document retrieval on which connection relation based upon the logical expression of a retrieval expression is reflected. SOLUTION: A document information storage means 1 stores documents together with key words extracted from the document so that they correspond to each other. A retrieval expression acquiring means 2 receives the retrieval expression generated by connecting retrieval key words by logical operators. A document counting means 3 specifies key words as objects of similarity judgement among the extracted key words stored in the document storage means 1 and calculates the number of various documents corresponding to the retrieval expression. A similarity calculating means 4 calculates the similarity between the retrieval expression that the retrieval expression acquiring means 2 has received and respective judgement object key words according to a calculation expression including the number of various documents as a variable. A relativity calculating means 5 calculates the relativity between the retrieval expression and each document according to the similarity by the judgement object key words obtained from the similarity calculating means 4 and the relative document information.