Abstract
The differential effects of belief in blood-type based personality theory on selective use of confirmatory information and confirmatory judgment in person perception is examined. In two experiments, participants were given behavioral information of a target person and asked to judge if the target person's blood type is hypothesized blood type. In both experiments, participants, regardless of the level of belief in blood type based personality theory, rated confirmatory information more important than other information. On the other hand, the judgments of the blood type of the target differed between those who believe in the theory and those who do not. Those who strongly believe in the theory tended to make more confirmatory judgments than those who do not. These results support the prediction that the effects of belief in blood-type based personality theory take different roles in different stages of person perception processes. Experiment 2 also examined the role of amount of knowledge in blood-type based personality theory on selective use of confirmatory information.
