15. The method of claim 12 wherein performing two or more voice recognition analyses having different speaker category assumptions includes: performing a first voice recognition based on an assumption that the voice signal is obtained from a male speaker; performing a second voice recognition based on an assumption that the voice signal is obtained from a female speaker; performing a third voice recognition based on an assumption that the voice signal is obtained from a child speaker.
12. The method of claim 1 wherein performing two or more voice recognition analyses on the voice signal includes performing two or more voice recognition analyses having different speaker category assumptions.