8. The text mining method of claim 7 , wherein the one of the first and second text data is generated by speech recognition.
8. The text mining method of claim 7 , wherein the one of the first and second text data is generated by speech recognition. 9. The text mining method according to claim 8 , further comprising setting confidences for the words of the one of the first and second text data generated by speech recognition, using a word graph obtained during the speech recognition.