Expert Judgment in Risk Analysis

Experts are often used to provide uncertainty distributions in risk analyses. They play an importantrole when insufficient data exist for quantification, or when the available data or models are conflicting. Multiplesteps are required in constructing a successful expert judgment process. These steps include selecting andframing the issues, identifying the experts, deciding upon an organization structure, and possibly combiningthe distributions from multiple experts.Expert judgments are normally given as probabilities or probability distributions that express the uncertaintyabout future events or unmeasured quantities. The goodness of probabilistic judgments is measured throughcalibration and information, which, in turn, can be measured through a scoring rule.Various behavioral and mathematical methods have been proposed for combining the judgments of experts.There is, however, no single method that has emerged as the best.