The Absent Role of Self-serving Bias in Ultimatum Games

Abstract: We conducted variations of the ultimatum bargaining game featuring a pie of SEK100 or SEK1000 and varying outside options for the respondents. The asymmetries in our setup allowed for self-serving bias, which distorts interpretations for a fair outcome. We observed relatively high rejection rates, as the subjects, despite their similar interests, stood on different positions given their self-serving judgments. However, we did not find any significant relationship between the magnitude of self-serving bias and bargaining impasse. The relationship remained insignificant when we controlled for a heavy anchor and the social comparison effect.