Abstract
Colic crying, which is a baby's abnormal crying induced by unknown causes, is a typical example of sounds giving unpleasant impressions to listeners. Recently, Mukai et al. suggested that the colic crying would cause the child abuse because of its unpleasantness. In this paper, we propose the extended pitch perturbation quotient (ePPQ) for the evaluation of unpleasantness of crying. It is shown that the ePPQ is an index to quantify instability of fundamental periods, which seems to be cause of unpleasantness of colic crying. The ePPQ for colic crying is significantly higher than that for crying cured by operation. Furthermore, as a result of subjective evaluations, it seems that there is a tendency for the scale of unpleasantness to be high when the ePPQ is high. Therefore, it is considered that the ePPQ is a useful index for evaluating unpleasantness for crying.
