Effects of echoic mimicry using hummed sounds on human-computer interaction

Our research goal is to investigate interpersonal relations involving empathy in human-computer interaction. We focus on mimicry behavior and its ability to elicit intentional stance of a partner in interaction. In this study, we conducted a psychological experiment to examine how prosodic mimicry by computers affects people. An interactive system in this experiment uses an animated character that mimics the prosodic features in a human's voice echoicly by synthesizing the hummed sounds. The sounds consist only of prosodic components similar to continuous humming of the open vowel /a/ or /o/ without any language information. The subjects completed a questionnaire to evaluate the character at different mimicry ratio. The results indicated the following possibilities: First, people favorably interpret a computer's simple response such as echoic mimicry using hummed sounds mixed with a slightly constant prosody response. Second, people may establish an interpersonal relations with a computer through such facilitated interaction. (C) 2002 Elsevier Science B.V. All rights reserved.