The Self-Serving Bias and the Use of Objective and Subjective Methods for Measuring Success and Failure

Students (N = 45) were asked to judge their recent exam performance on a success versus failure rating scale. They were also asked to make causal attributions for their test performance on an internal versus external scale. The students' scores were divided into success and failure groups by using both subjective (self-reported outcome) and objective (actual exam scores) definitions of outcome. For both methods, the success group had higher internal attributions for their performance than did the failure group. The effect size for the subjective methods of defining outcome, however, produced a stronger self-serving bias that did the objective definition.