Towards Analysis of Expressive Gesture in Groups of Users: Computational Models of Expressive Social Interaction

In this paper we present a survey of our research on analysis of expressive gesture and how it is evolving towards the analysis of expressive social interaction in groups of users. Social interaction and its expressive implications (e.g., emotional contagion, empathy) is an extremely relevant component for analysis of expressive gesture, since it provides significant information on the context expressive gestures are performed in. However, most of the current systems analyze expressive gestures according to basic emotion categories or simple dimensional approaches. Moreover, almost all of them are intended for a single user, whereas social interaction is often neglected. After briefly recalling our pioneering studies on collaborative robot-human interaction, this paper presents two steps in the direction of novel computational models and techniques for measuring social interaction: (i) the interactive installation Mappe per Affetti Erranti for active listening to sound and music content, and (ii) the techniques we developed for explicitly measuring synchronization within a group of users. We conclude with the research challenges we will face in the near future.