Sources of Bias in Judgment and Decision Making

Abstract

Sources of bias in confidence and probability judgments, for example conservatism, overconfidence, and subadditivity, are some of the most important and rigorously researched topics within judgment and decision making. However, despite the seemingly obvious importance of memory processes on these types of judgments, much of this research has focused on external factors independent of memory processes, such as the effects of various types of elicitation format. In this chapter, we review the research relevant to commonly observed effects related to confidence and probability judgment, and then provide a memory-process account of these phenomena based on two models: Minerva-DM, a multiple-trace memory model; and HyGene, an extension of Minerva-DM that incorporates hypothesis generation. We contend that accounting for the dependence of judgments on memory provides a unifying theoretical framework for these various phenomena, as well as cognitive models that accurately reflect real-world behavior.