Abstract: A language model 114 for speech recognition is developed from a text database 122 through offline modeling 130 (solid line arrow). A transcript is generated online by executing a speech recognition processing 110 using an acoustic model 112 and a language model 114 when a user utters a retrieval request. Next, a text retrieval processing 120 is executed using the transcribed retrieval request, and then outputs the retrieval results in order from the most relevant. Information is then acquired from the top-ranked texts of the retrieval results and is subjected to modeling 130, the speech recognition language model is refined (dotted line arrow), and speech recognition and text retrieval are then carried out again. This allows improvement in accuracy of recognition and retrieval compared to the initial retrieval.