When should animated agents give additional instructions to users? - Monitoring user’s understanding in multimodal dialogues -

In multimodal communication, verbal and nonverbal behaviors such as gestures and manipulating objects in a workspace occur in parallel, and are coordinated in proper timing to each other. This paper focuses on the interaction between a beginner user using a video recorder application on PC and a multimodal animated help agent, and presents a probabilistic model of fine-grained timing dependencies among different behaviors of different modalities. First, we collect user-agent dialogues using a Wizard-of-Oz experimental setting, and then the collected verbal and nonverbal behavior data will be used to build a Bayesian network model, which can predict the likelihood of successful mouse clicks in near future, given evidence associated with the status of speech, agent´s gestures and user´s mouse actions. Finally, we attempt to determine proper timing when the agent should give additional instructions by estimating the likelihood of a mouse click occurrence.