In this thesis I propose a framework for normal and extensive form games where players can use Knightian uncertainty strategically. In such Ellsberg games, ambiguity-averse players may render their actions objectively ambiguous by using devices such as Ellsberg urns, in addition to the standard...

A game-theoretic framework that allows for explicitly randomized strategies is used to study the effect of ambiguity aversion on equilibrium outcomes. The notions of "independent strategies" as well as of "common priors" are amended to render them applicable to games in which players lack...

The traditional model of sequential decision making, for instance, in extensive form games, is a tree. Most texts define a tree as a connected directed graph without loops and a distinguished node, called the root. But an abstract graph is not a domain for decision theory. Decision theory...

We consider a best-of-three Tullock contest between two ex-ante identical players. An effort-maximizing designer commits to a vector of player-specific biases (advantages or disadvantages). In our benchmark model the designer chooses victory-dependent biases (i.e., the biases depend on the...

This paper analyzes which type of intrinsic preferences drive an agent's behavior in a sequential public good game depending on whether the agent is first or second mover. Theoretical predictions are based on heterogeneity of individuals in terms of social and risk preferences. We modelize...

This paper studies the behavior of two firms after a new investment opportunity arises. Examples of such an investment are technology adoption or market entry. Firms either invest immediately or wait until market uncertainty is resolved. Two types of separating equilibrium are possible when...

For choice with deterministic consequences, the standard rationality hypothesis is ordinality, i.e., maximization of a weak preference ordering. For choice under risk (resp. uncertainty), preferences are assumed to be represented by the objectively (resp. subjectively) expected value of a von...

This paper studies a general class of time-inconsistent stochastic control problems under ambiguous covariance matrix. The time-inconsistency is caused in various ways by a general objective functional and thus the associated control problem does not admit Bellman's principle of optimality....

This paper studies a class of robust mean-variance portfolio selection problems with state-dependent risk aversion. Model uncertainty, in the sense of considering alternative dominated models, is introduced to the problem to reflect the investor's ambiguity aversion. To characterize the robust...