Patent ID: 6885990

Claim:
A method of speech recognition based interactive information retrieval for ascertaining and retrieving a target information of a user by determining a retrieval key entered by the user using a speech recognition processing, comprising the steps of: (a) storing retrieval key candidates that constitute a number of data that cannot be processed by the speech recognition processing in a prescribed processing time as recognition target words, in a plurality of statistically hierarchized databases provided in a speech recognition database, where lower level statistically hierarchized databases contain increasingly larger part of the retrieval key candidates such that a lower level statistically hierarchized database contains all the retrieval key candidates; (b) requesting the user by a speech dialogue with the user to enter a speech input indicating the retrieval key, and carrying out the speech recognition processing for the speech input with respect to all of the plurality of statistically hierarchized databases in parallel, to sequentially obtain respective recognition results indicating recognition retrieval key candidates and their recognition likelihoods; (c) selecting those recognition retrieval key candidates which have recognition likelihoods that are exceeding a prescribed likelihood threshold as recognition retrieval key leading candidates, for each statistically hierarchized database for which the speech recognition processing is completed; and (d) controlling a next speech dialogue with the user according to whether a prescribed condition that a number of the recognition retrieval key leading candidates is less than or equal to a prescribed number but not zero is satisfied or not.