Abstract:

The base-rate neglect refers to the phenomenon that individuals tend to underestimate or neglect base-rate information in probability judgment and decision-making. The phenomenon is widespread in daily behavioral decision-making. Since the concept of base-rate neglect has been proposed, the studies of its psychological mechanisms have reached well-documented results and conclusions. But the exploration for its influence factors turned out to be a conservative, thus few researches tried to shed light on its application. What’s more, there is little empirical study of base-rate neglect in China. Therefore, this study aims to verify the base-rate neglect in real decision-making situations, and explore how the psychological distance would affect the base-rate neglect. Study 1 carried out one experiment with 2 (temporal distance: distant vs. near) × 2 (base rate: high vs. low) between-subject design to examine the moderate effect of temporal distance. A total of 121 students were recruited. The results showed that the temporal distance affected the base-rate neglect under the selection circumstances, and that the base-rate neglect effect was weakened along with the increasing temporal distance, thus individuals tended to make probability judgments based on base rate. Similarly, study 2 explored the effect of spatial distance on the base-rate neglect with 2 (spatial distance: distant vs. near) × 2 (base rate: high vs. low) between-subject design. A total of 122 students were recruited. The results indicated that the spatial distance affected the base-rate neglect in the selection circumstances, and that the base-rate neglect effect was weakened along with the increasing spatial distance, thus individuals tended to make probability judgments based on base rate. The same with the pattern in study 1 and study 2, study 3 explored the effect of social distance on the base-rate neglect with 2 (social distance: distant vs. near) × 2 (base rate: high vs. low) between-subject design. A total of 144 students were recruited. It was found that the social distance affected the base-rate neglect in the selection circumstances, and that the base-rate neglect effect was weakened along with the increasing social distance, thus individuals tended to make probability judgments based on base rate. In sum, three studies provided consistent evidences that different dimensions of psychological distance, namely temporal distance, spatial distance and social distance could affect the relative weight according to case description information as well as base rate information in the base-rate neglect situations.

Key words: base-rate neglect, psychological distance, temporal distance, spatial distance, social distance