This type of predictive models has been mostly studied in the context of embodied conversational agents (Nakano et al., 2003;Nakano et al., 2007).
backchannel feedback (the nods and paraverbals such as "uh-hu" and "mm-hmm" that listeners produce as someone is speaking) has received considerable interest due to its pervasiveness across languages and conversational contexts and this paper addresses the problem of how to predict and generate this important class of dyadic nonverbal behavior.