実験社会科学 - 実験が切り開く21世紀の社会科学 -

司会　竹村和久（早稲田大学意思決定研究所）

1. Vladimir Volokhonsky氏　 （ロシア国立サンクトペテルブルグ大学心理学部）
POST-HEURISTIC DISSONANCE

We are based on the assumption that there is unconscious knowledge of the true answers to some questions. People, who are giving incorrect answers resulting from the use of heuristics, therefore, should experience some level of cognitive dissonance. It was decided to check it on the example of the anchoring effect. People's estimates of uncertain quantities are commonly influenced by irrelevant values (anchoring effect). We suppose the presence of the cognitive dissonance reduction related with anchoring. 28 participants filled out a form with anchoring-loaded task twice with a three week interval. After the second test procedure the frequency of bias towards the anchor point exceeded the frequency of the opposite bias. This new secondly formed bias was accompanied by increase of the assurance level. Nonlinear correlation between assurance and anchoring levels was also found. These results suggest the presence of the cognitive dissonance after an anchoring.The Study II showed interaction between anchor remoteness and cognitive dissonance level. Five levels of anchor remoteness were tested for reaction time (measurement of cognitive dissonance). Nonlinear correlation has been found: the farther was the anchor, the larger was the cognitive dissonance, but there are increase of cognitive dissonance at the zero anchor remoteness. In the Study III also anchor remoteness was tested for the produced anchoring effect level. Inflection of the functional curve were supposed, but anchoring effect continued to increase steadily in correspondence with increase of anchor remoteness up to 500% remoteness point.

２．Michael W. Myers氏 （早稲田大学意思決定研究所）
The Structure of Self-Other Overlap and its　Relationship to Perspective Taking

Mixed results for self-other overlap as a mediator of perspective taking’s pro-social effects may be due to the use of different methodologies and scales to measure self-other overlap. To test this idea, three studies investigate the structure of self-other overlap and examine how perspective taking may affect only certain facets of self-other overlap. To test the conceptual equivalence of different overlap measures, in Study 1, participants (n = 132) completed several previously used measures of overlap for two targets: their best friend. Factor analyses revealed two distinct factors of self-other
overlap - perceived closeness and overlapping representations. Perceived closeness but not overlapping representations was associated with relationship quality. Studies 2 (n = 118) and 3 (n = 118) manipulated perspective taking, using a target person who was similar and dissimilar, respectively, to participants. Results replicated the same factor structure from Study 1, and found that perspective taking had different effects on the two factors. Together, these results suggest that self-other overlap is a multi-dimensional construct with only the dimension of perceived closeness being associated with psychological responses related to perspective taking