Cognitive Factors Affecting Subjective Probability Assessment

Prior probabilities are central to Bayesian statistics. The Bayesian paradigm assumes that people can express uncertainty in terms of subjective probability distributions. This article will consider Hogarth's 1975 assessment that \man is a selective, sequential information processing system with limited capacity,. .. ill-suited for assessing probability distributions." Particular attention will be paid to when people make nor-matively \good" or \poor" probability assessments, what techniques are eeective in eliciting \good," coherent probability assessments, and on how these ideas are relevant to the practicing Bayesian statistician. While there are situations where experts can make well-calibrated judgments, it will be argued that more research needs to be done into the eeects of expertise, training, and feedback.