18. The data process unit according to claim 17 , further comprising: a specific speaker specifying unit for specifying a specific speaker among the speakers; a similarity evaluating unit for evaluating a similarity in speech between the specific speaker and the target speaker based on the position of the second speech data and a fourth pattern model of the specific speaker in the acoustic space; and an evaluation result display unit for displaying an evaluation result evaluated by the similarity evaluating unit, wherein the positional relationship information display unit displays information about a positional relationship between the second speech data and the fourth pattern model in the acoustic space based on the position of the second speech data and the fourth pattern model.
21. The data process unit according to claim 18 , wherein: the acoustic space is composed of the first pattern models generated from the first speech data made in a plurality of speech styles; and the similarity evaluating unit evaluates the similarity in each of the speech styles.