The Effects of an Embodied Conversational Agent's Nonverbal Behavior on User's Evaluation and Behavioral Mimicry

Against the background that recent studies on embodied conversational agents demonstrate the importance of their behavior, an experimental study is presented that assessed the effects of different nonverbal behaviors of an embodied conversational agent on the users ́ experiences and evaluations as well as on their behavior. 50 participants conducted a conversation with different versions of the virtual agent Max, whose nonverbal communication was manipulated with regard to eyebrow movements and selftouching gestures. In a 2x2 between subjects design each behavior was varied in two levels: occurrence of the behavior compared to the absence of the behavior. Results show that self-touching gestures compared to no self-touching gestures have positive effects on the experiences and evaluations of the user, whereas eyebrow raising evoked less positive experiences and evaluations in contrast to no eyebrow raising. The nonverbal behavior of the participants was not affected by the agent’s nonverbal behavior.