What happens when a robot favors someone? How a tour guide robot uses gaze behavior to address multiple persons while storytelling about art

We report intermediate results of an ongoing study into the effectiveness of robot gaze behaviors when addressing multiple persons. The work is being carried out as part of the EU FP7 project FROG and concerns the design and evaluation of interactive behaviors of a tour guide robot. Our objective is to understand how to address and engage multiple visitors simultaneously. The robot engages small groups of visitors in interaction and offers information on objects of interest. In the current experiment, a robot tells three visitors about two different paintings. A 2 × 2 independent factorial design is used. The robot engages the three visitors in mutual gaze by looking at the artwork while talking about it vs. only looking at the visitors (between subject-groups). Also, the robot `favors´ one of the three participants by directing it´s gaze at them more frequently and longer compared to the other two participants. We are interested to find out whether gaze at the object of interest and favoring through gaze has an effect on the user´s experience and knowledge retention. Preliminary results indicate that a robot that engages visitors in mutual gaze is seen as more humanlike and `favoring´ a person in a small group positively influences attitudes toward the robot.