Individual and Group Biases in Value and Uncertainty Judgments

Behavioral decision research has demonstrated that value and uncertainty judgments of decision makers and experts are subject to numerous biases. Individual biases can be either cognitive, such as overconfidence, or motivational, such as wishful thinking. In addition, when making judgements in groups, decision makers and experts might be affected by group-level biases. These biases can create serious challenges to decision analysts, who need judgments as inputs to a decision or risk analysis model, because they can degrade the quality of the analysis. This chapter identifies individual and group biases relevant for decision and risk analysis and suggests tools for debiasing judgements for each type of bias.