In this study, we investigate whether group norms occur in human–robot groups. At present, there are a number of studies that examine social robots’ ways of responding, gesturing, and displaying emotion. However, sociality implies that robots not only exhibit human-like behaviors, but also display the tendency to adapt to a group of individuals. For robots to exhibit sociality, they must adapt to group norms without being told by the group members how to behave. Group norms refer to the unwritten, unspoken, and informal rules that are present in a group of individuals. In a previous study, we demonstrated that a robot model learned group norms in human groups [1]. In the present study, we investigate whether group norms occur in human–robot groups. To this end, we prepared quizzes with unclear and vague answers, and instructed participants to take the quizzes with the robot. The results of the quiz experiments demonstrated that the robot considered group norms in human–robot groups when making decisions; thus, group norms occurred in human–robot groups.

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