October 4: Dov Samet (QSMS Seminar)

Dov Samet from the Coller School of Management at Tel Aviv University will be presenting his paper “Desirability” on October 4th at 10 AM, room QA405. One-to-one meetings with the speaker can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).

Abstract:  We propose a model of an agent’s probability and utility that is a compromise between Savage (1954) and Jeffrey (1965). In Savage’s model the probability-utility pair is associated with preferences over acts which are assignments of consequences to states. The probability is defined on the state space, and the utility function on consequences. Jeffrey’s model has no consequences, and both probability and utility are defined on the same set of propositions. The probability-utility pair is associated with a desirability relation on propositions. Like Savage we assume a set of consequences and a state space. However, we assume that states are comprehensive, that is, each state describes a consequence, as in Aumann (1987). Like Jeffrey, we assume that the agent has a preference relation, which we call desirability, over events, which by definition involves uncertainty about consequences. For a given probability and utility of consequences, the desirability relation is presented by conditional expected utility, given an event. We axiomatically characterize desirability relations that are represented by a probability-utility pair. We characterize the family of all the probability-utility pairs that represent a given desirability relation.