A product set of pure strategies is a prep set (prep is short for preparation) if it contains at least one best reply to any consistent belief that a player may have about the strategic behavior of his opponents. Minimal prep sets are shown to exists in a class of strategic games satisfying...

Many decision models in marketing science and psychology assume that a consumer chooses by proceeding sequentially through a checklist of desirable properties. These models are contrasted to the utility maximization model of rationality in economics. We show on the contrary that the two...

We show that whenever a decision maker reasons about an optimal decision he is able to find one, even with non-transitive preferences. The existence of a reasoning process allows him to strategically manipulate how he reasons. A reasoning strategy that is robust against (finite) deviations is...

A rigorous reconstruction of scenario-based real choice making reveals the incompleteness of decision-modeling and the practical prevalence of uncertainty. Theoretically complete models conceal it. As a remedy a scenario-based procedure of coping with uncertainty can prescribe how the boundedly...

This paper analyses the behavior of an individual who wants to maximize his utility function, but he is not able to evaluate it. There are many ways to choose a single alternative from a given set. We show that a unique utility maximizing procedure exists. Choices induced by this optimal...