18. The non-transitory computer readable storage medium for recording a speaker selecting program according to claim 15 , wherein the speaker score calculation step includes causing a computer accessible to an utterance dependence storage means that stores data indicating a temporal dependence between utterances, to calculate a likelihood by reflecting the stored data indicating the temporal dependence between utterances.
15. The non-transitory computer readable storage medium for recording a speaker selecting program according to claim 14 , wherein the speaker score calculation step includes causing the computer to calculate, as the first likelihood, a long-time likelihood based on a voice signal of a relatively long time, and to calculate, as the second likelihood, a short-time likelihood based on a voice signal of a relatively short time, the first selection step includes causing the computer to execute long-time selection step for selecting speakers corresponding to a predetermined number of speaker models the long-time likelihood of which is high, and the second selection step includes causing the computer to execute a short-time selection step for selecting speakers corresponding to speaker models the number of which is smaller than the predetermined number and the short-time likelihood of which is high.