We characterize preferences over acts that can be represented by a utility function and a multiple-prior, such that an act f is preferred to act g if there is a prior under which the expected utility induced by f is higher than that induced by g. These preferences are referred to as justifiable...

We consider a sequential decision problem where the decision maker is informed of the actual payoff with delay. We introduce a new condition, which generalizes the condition given by Blackwell and ensures that the decision maker can approach a fixed closed and convex set under delay. We show how...