RETRIEVAL DEVICE, RETRIEVAL PROGRAM, AND RETRIEVAL METHOD

摘要

PROBLEM TO BE SOLVED: To provide a retrieval device capable of efficiently performing retrieval with a high precision rate. SOLUTION: The retrieval device for retrieving a document according to a designated retrieval word from a plurality of documents includes: a retrieval word pair generation part which generates at least one retrieval word pair including a first retrieval character string having a length of the number of index characters which is included in the retrieval word, and a second retrieval character string having a length of the number of index characters which is at a position shifted from the first retrieval character string by an extent corresponding to the preliminarily determined number of offset characters with respect to each of a plurality of documents; a retrieval part which retrieves documents having both the first retrieval character string and the second retrieval character string as index words from an index database with respect to each retrieval word pair; a calculation part which calculates scores on the basis of frequencies with which the first retrieval character strings and the second retrieval character strings of respective retrieval word pairs are included in respective documents; and a selection part which selects a document to be output as a retrieval result out of the plurality of documents on the basis of respective scores of the plurality of documents. COPYRIGHT: (C)2009,JPO&INPIT