ABSTRACT
The chapter begins by distinguishing personal opinion, professional opinion, and expert judgment, noting the appropriate use of each of these in characterizing uncertainty with probability distributions for risk assessment. Conditions requiring a formal expert elicitation are presented. The range of uncertain values that may be sought by expert elicitation are reviewed and subjective probability distributions become the focal point leading up to a discussion of different expert elicitation protocols. The common biases and heuristics that can interfere with the elicitation of subjective probabilities are discussed. They include overconfidence, availability, representativeness, anchor and adjust, motivational, confirmation, and framing bias. The role of calibration in expert elicitation is discussed before the chapter concludes by considering ways of handling elicitations from multiple experts.
