The rare preference effect: Statistical information influences social affiliation judgments.

Shared preferences—liking the same things—facilitate and strengthen bonds between individuals. However, not all shared preferences are equally meaningful; sharing a rare preference with someone is often more exciting and meaningful than sharing a common preference. Here we present evidence for the rare preference effect: Participants chose to interact with (Experiment 1), and endorsed interactions between (Experiment 2), individuals who shared a rare preference, rather than those who shared a common preference, and this tendency increased with the relative rarity of the preference. While having a preference usually implies knowing and liking something, the presence of shared knowledge alone was sufficient to give rise to the rare preference effect (Experiments 3 & 4). Further, we find that social affiliation judgments are modulated by the causal process by which individuals came to have shared knowledge: Participants preferred to interact with someone who acquired a shared preference deliberately rather than accidentally (Experiment 5). In addition to the many cultural and emotional factors that drive mutual attraction, these results suggest that people’s decisions about with whom to interact are systematically influenced by the statistics of the social environment.