When Others Agree More Closely: Judgment Similarity Influences Conformity

Conformity is strongly shaped by perceived consensus, yet prior research has predominantly examined this process in discrete-choice contexts, where consensus is typically operationalized as the size of a uniform majority. In continuous real-world environments, however, social judgments naturally vary, making judgment similarity a potentially important cue for consensus. The present study investigated whether similarity among others' judgments modulates conformity. Across two perceptual estimation experiments, participants first estimated the location of a briefly presented target and then revised their estimates after viewing two partners' responses. In Experiment 1, in which partner responses were attributed to humans, participants showed greater conformity when partners' estimates were highly similar. Computational modeling formalized this process within a Bayesian belief-updating framework, suggesting that judgment similarity increased the evidential weight assigned to social information. In Experiment 2, this similarity-dependent effect was attenuated when the same response structure was explicitly attributed to computer programs rather than human agents. These findings indicate that conformity in continuous judgment spaces cannot be fully explained by a domain-general statistical heuristic or passive imitation alone. Instead, individuals appear to evaluate both the content of social evidence and the attributed properties of its source, using judgment similarity as a cue for integrating information from others.