We describe a variety of machine-learning techniques that are being applied to social multiuser human–
robot interaction using a robot bartender in our scenario. We first present a data-driven approach to social
state recognition based on supervised learning. We then describe an approach to social skills execution—
that is, action selection for generating socially appropriate robot behavior—which is based on reinforcement
learning, using a data-driven simulation of multiple users to train execution policies for social skills. Next,
we describe how these components for social state recognition and skills execution have been integrated
into an end-to-end robot bartender system,