Comparing Behavioral and Self-Report Measures of Embodied Agents’ Social Presence in Immersive Virtual Environments

Recent work [1, 2, 3] has argued that subjective questionnaires may be ineffective at measuring copresence towards agents and avatars in immersive virtual environments (IVEs). The current work directly compares self-report and behavioral measures of copresence. In two studies, we measured the interpersonal distance between participants and either an embodied tutoring agent or an unfamiliar embodied agent as they walked through an IVE. We found that participants yielded more personal space to embodied tutors compared to other embodied agents in both studies. However, self-report measures of copresence, likability, status, or interest did not reveal any differences between embodied tutors and strangers. These findings suggest that nonverbal behavior may be a more sensitive measure of the copresence and general influence of embodied agents than self-report measures. While alternative explanations for these findings certainly exist, there are clearly strong advantages of using behavioral measures to study copresence as a compliment to other measures. Given that a large portion of current research evaluating collaborative environments utilizes self-report measures only, the current findings are particularly notable.