Entrainment of Rate of Utterances in Speech Dialogs Between Users and an Auto Response System

Entrainment, a physical phenomenon in which one individual’s expressed information synchronizes with another’s and vice versa, can be observed between two communicators who are in smooth interaction. In this study, we focused on the “rate of utterances” as communicators’ expressed information, and then conducted an experiment to observe whether entrainments exist in the rate of utterances in speech dialogs between users and an auto response system. Specifically, participants were asked to read given dialog scripts with an auto response system that replied with different rates of utterances. The results revealed that 1) when the system’s rates of utterances were faster, the participants produced faster rates of utterances, 2) when the system’s rates were slower, participants spoke at slower rates. These results suggest the existence of entrainments of rates of utterances in speech dialogs between participants and an auto response system.