The interaction game: A reciprocity-based minimal paradigm for the induction of social distance

The investigation of how social distance affects psychological phenomena has relied mostly on comparisons between strangers and acquaintances. Such an operationalization suffers from a confound between social distance and acquaintance. We propose an experimental paradigm that manipulates social distance while avoiding the aforementioned confound. By relying on reciprocity and known social tie formation mechanisms, the Interaction Game provides researchers with a powerful tool for the investigation of social distance effects without inducing negative affective or emotional states. Four preregistered experiments demonstrate the internal and external validity of the paradigm. The capability of manipulating social distance in a targeted manner constitutes a critical step towards advancing our knowledge of the impact of such metrics on human cognition and behavior. Moreover, Experiment 4 demonstrates that the Interaction Game can induce social distance that is free of acquaintanceship, and that such a minimal manipulation is sufficient for inducing close-other favoritism in a social discounting task. These findings expand our understanding of social distance as a powerful mechanism underlying social judgments and behaviors.