Learning, adopting, and enforcing a psychophysical social norm

Online communities are virtual spaces formed as open collectives of distributed and often unfamiliar individuals who share common interests. To be successful, online communities need their members to understand and follow community norms. Members learn the norms of a community by observing other people and the consequences of their behavior, seeing codes of conduct, or receiving feedback on their own actions in the form of moderation. What contribution does each form of learning make to the formation, learning, and enforcement of a social norm? To answer the question, we study the r/truerateme subreddit, a community within Reddit that is dedicated to the preservation of a norm of particular interest to the vision science community: intersubjective notions of beauty derived from facial aesthetics. In particular, participation in the r/truerateme community entails rating and commenting on other members' appearance using a rating scale defined only by the consensus of the community, not by any one member's subjective impressions. Studying this community thus provides a unique opportunity to leverage psychophysical techniques to understand intersubjective cultural phenomena because of how amenable this particular norm is to quantitive characterization. We build a computational model that extends the cultural consensus theory framework to identify the cultural consensus beauty for a given face, each member' competence, and individual differences in the rate of learning the shared social norms. We find that user's incidental perceptual alignment with the psychophysical norm before enculturation predicts involvement in the community. Further, experience in rating items is an important indicator for group perceptual learning of the shared social norms. Through computational modeling and demonstrations, we suggest that perceptual adaptation of the community can rapidly recalibrate members' responses to a shared social norm.