Often people must make judgments that require them to consider how a target entity (e.g., a person, object, event) compares to a specific referent or set of referents. One such judgment is a probability judgment. When asked "How likely is Michigan to win the Big Ten Basketball Tournament?" a respondent must consider not only the strength of the Michigan team, but also the strengths of other teams in the tournament. Another such judgment is an explicit comparative judgment. When asked "How good is Michigan compared to the other teams in the Big Ten?" a respondent must again consider not only the strength of the Michigan team, but also the strengths of other teams in the Big Ten. Understanding these two types of judgment, which can be collectively called referent-dependent judgments, is critical because they underlie decisions and behaviors within wide variety of life's domains. For example, a doctor's confidence that a patient has Disease A rather than Disease B or C can influence treatment decisions; an employer's judgment of how Manager X's productivity compares to other managers in the company might be the basis for a merit raise; and a consumer's judgment of how safe Minivan Y is relative to other minivans under consideration might influence the amount of money the consumer will spend on that minivan. Despite the structural overlap between probability and comparative judgments, these two forms of judgment have not been systematically compared or simultaneously tested within the same general paradigm. The proposed research will investigate the key commonalities and differences among these two forms of referent-dependent judgments. The proposal also outlines a framework for understanding how three major types of biases (egocentrism, focalism, and multiple-referent biases) have the potential to influence both probability and comparative judgments. Many of the proposed experiments will test for possible differences in how the biases might influence the two forms of judgment. Overall, these studies would facilitate the development of a theoretical framework that provides a broader and more synthetic understanding of the major processes that mediate both biased and unbiased referent-dependent judgments.
