Abstract This paper describes a behavioural model used to simulate realistic eye‐gaze behaviour and body animations for avatars representing participants in a shared immersive virtual environment (IVE). The model was used in a study designed to explore the impact of avatar realism on the perceived quality of communication within a negotiation scenario. Our eye‐gaze model was based on data and studies carried out on the behaviour of eye‐gaze during face‐to‐face communication. The technical features of the model are reported here. Information about the motivation behind the study, experimental procedures and a full analysis of the results obtained are given in [ 17 ].

This paper presents an experiment designed to investigate the impact of visual and behavioral realism in avatars on perceived quality of communication in an immersive virtual environment. Participants were paired by gender and were randomly assigned to a CAVE‘-like system or a head-mounted display. Both were represented by a humanoid avatar in the shared 3D environment. The visual appearance of the avatars was either basic and genderless (like a "match-stick" figure), or more photorealistic and gender-specific. Similarly, eye gaze behavior was either random or inferred from voice, to reflect different levels of behavioral realism. Our comparative analysis of 48 post-experiment questionnaires confirms earlier findings from non-immersive studies using semi-photorealistic avatars, where inferred gaze significantly outperformed random gaze. However responses to the lower-realism avatar are adversely affected by inferred gaze, revealing a significant interaction effect between appearance and behavior. We discuss the importance of aligning visual and behavioral realism for increased avatar effectiveness.

In this paper we describe an experiment designed to investigate the importance of eye gaze in humanoid avatar's representing people engaged in conversation. We compare responses to dyadic conversations in four mediated conditions: video, audio-only, and two avatar conditions. The avatar conditions differed only in their treatment of eye gaze. In the random-gaze condition the avatars head and eye animations were unrelated to conversational flow. In the informed-gaze condition, they were related to turn-taking during the conversation. The head animations were tracked and the eye animations were inferred from the audio stream. Our comparative analysis of 100 post-experiment questionnaires showed that the random-gaze avatar did not improve on audio-only communication. The informed-gaze avatar significantly outperformed the random-gaze model and also outperformed audio-only on several response measures. We conclude that an avatar whose gaze behaviour is related to the conversation provides a marked improvement on an avatar that merely exhibits liveliness.