Comparison opportunity and judgment revision

Prior evaluations are frequently challenged and need to be revised. We prop ose that an important determinant of such revisions is the degree to which the challenge provides an opportunity to compare the target against a compe titor. Whenever a challenge offers an opportunity; the information containe d in the challene will carry a disproportionate weight in the revised judgm ents. We call this proposition the comparison-revision hypothesis. In Exper iments 1-3, we manipulated comparison opportunity by varying the format of the challenge and examined the weights assigned to different inputs in the revised judgments. The results indicate that prior information about the ta rget receives a greater weight under a noncomparative challenge (which prov ides information only about the target) than under a comparative challenge (which compares the target with a competitor). In contrast, information pre sented in the challenge receives a greater weight under a comparative chall enge than under a noncomparative challenge. Interestingly, when presented i n a comparative format, the information contained in the challenge received a relatively disproportionate weight even when the attributes presented in the challenge were less important than those on which the prior target eva luations were based. Results from Experiment 4 suggest that, under certain conditions, even a noncomparative challenge from a superior competitor can provide strong comparison opportunity and thus cause greater revisions in t he prior evaluations of the target. Specifically, a greater elaboration of the initial target information and a high degree of commensurability betwee n the target and competitor information jointly promote comparison opportun ity and thus cause greater revisions of the prior target judgments. Our fin dings offer important extensions to previous research on the effects of amo unt and elaboration of prior target information on subsequent judgment revi sion. (C) 1999 Academic Press.