What If I Speak Now?: A Decision-Theoretic Approach to Personality-Based Turn-Taking

Embodied conversational agents, which are increasingly prevalent in our society, require turn-taking mechanisms that not only generate fluent conversations but are also consistent with the personality and interpersonal stance required in the given context. We present a decision-theoretic approach for deriving the turn-taking behavior of such an agent from the personality it is meant to convey. For this we gathered relevant theories from psychology and communications research, as well as related systems employing utility-based reasoning. On this basis we describe the construction of an influence diagram which decides between acting and waiting based on those actions' expected utility for the agent's personality-related interaction goals. To test our approach, we integrated our model into an application which simulates conversations between two virtual characters. We then evaluated our prototype by presenting videos of those conversations in an online survey. Our results confirmed that differences in an agent's speaking behavior, generated from different Extraversion configurations in our model, lead to the intended perceptions of its Extraversion, Agreeableness and Status.