Two types of measures of probabilistic uncertainty are introduced and investigated. Dispersion measures report how diffused the agent’s second-order probability distribution is over the range of first-order probabilities. Robustness measures reflect the extent to which the agent’s assessment of the prior (objective) probability of an event is perturbed by information about whether or not the event actually took place. The properties of both types of measures are investigated. The most obvious type of robustness measure is shown to coincide with one (...) of the major candidates for a dispersion measure, the mean square deviation measure. (shrink)

This paper argues that Isaac Levi's account of preference reversals is only a limited success. Levi succeeds in showing that an agent acting in accord with his theory may exhibit reversals. Nevertheless, the specific account that Levi presents in order to accommodate the behavior of experimental subjects appears to be disconfirmed by available evidence.