On the basis of the statistical concept of waiting time and on computer simulations of the "probabilities of nonoccurrence" (p. 457) for random sequences, Hahn and Warren (2009) proposed that given people's experience of a finite data stream from the environment, the gambler's fallacy is not as gross an error as it might seem. We deal with two…

An integration of two different approaches to the psychology of causal induction is proposed that overcomes the problems associated with each. The proposal results in a causal power theory of the probabilistic contrast model of P. W. Cheng and L. R. Novick (1990). (SLD)

The development of probability judgment is explained in terms of working memory, composed of four types of storage operations and three types of processing operations. Age changes in probability judgment were related to changes in frequency retrieval, which stem from changes in constraints on work-space capacity. (Author/RD)

A decision field theory is proposed and used to explain motivational and cognitive mechanisms that guide the deliberation process involved in decisions made under uncertainty. Decision theories are extended into the stochastic-dynamic category. The proposed theory is compared with four other theories of decision making under uncertainty. (SLD)

A rational model of human categorization behavior is presented that assumes that categorization reflects the derivation of optimal estimates of the probability of unseen features of objects. A case is made that categorization behavior can be predicted from the structure of the environment. (SLD)

A descriptive model of how people make judgments under ambiguity is proposed. Two factors are reflected in the model: (1) the amount of ambiguity, which affects the size of the simulation, and (2) one's attitudes toward ambiguity. The model is tested in four experiments using individual and group analyses. (Author/LMO)