Response timing generation and response type selection for a spontaneous spoken dialog system

If a dialog system can respond to a user as naturally as a human, the interaction will appear smoother. In this research, we aim to develop a dialog system that emulates human behavior in a chat-like dialog. The proposed system makes use of a decision tree to generate chat-like responses at the appropriate times. These responses include “aizuchi” (back-channel), “repetition”, “collaborative completion”, etc. The system also reacts robustly to the user's overlapping utterances (barge-in) and disfluencies. The subjective evaluation shows that there is a high degree of naturalness in the timing of ordinary responses, overlap, and aizuchi, and that the dialog system exhibits user-friendly behavior. The recorded voices system was preferred, and almost all subjects felt familiarity with aizuchi, and the barge-in was also useful.