A choice problem is risky (respectively ambiguous) if the decision maker is choosing between probability distributions (respectively sets of probability distributions) over utility relevant consequences. We provide an axiomatic foundation for and a representation of continuous linear preferences...

A multiple-prior decision maker is open-minded if she can describe, as subjective uncertainty, all convex sets of distributions over payoff relevant consequences. Theorem 1: open-mindedness is equivalent to the ability to subjectively describe both the uniform distribution on an interval and the...