Essays on game theory and coordination problems

The primary topic of the dissertation is game theory and coordination problem. It consists of three chapters, each of which studies a different economic environment under this main topic. In Lender of Last Resort Policy in Global Game and Role of Depositors’ Aggregate Behavior as Signaling, we construct a global-game Lender of Last Resort (LLR) model in which the LLR authority is an explicit player and examine the role of depositors * aggregate behavior. It is shown that (1) depositors’ aggregate behavior operates as a signal to the LLR authority about banks’ solvency, (2) the optimal LLR policy is to help only illiquid but solvent banks, and (3) whenever the LLR facility is utilized, optimal lending rates are strictly positive and conditionally punitive in that they take the highest level possible under the restriction that they enable solvent but illiquid banks to survive. In Delegation Games with Implementability in Weakly Undominated SPNE, a general two-principal two-agent delegation environment is examined. We employ a refined SPNE (weakly undominated SPNE, U-SPNE) as the equilibrium concept, while keeping the notion of the implementability unchanged. It is shown that in certain classes of 2x2 games – including prisoners’ dilemma, coordination games, and battle of sexes – every efficient outcome is fully implementable in U-SPNE. Next, we investigate a Bertrand delegation game. After pointing out that price setting behaviors derived by existing notion of “implementability with mutually rational players”are hard to justify from the standard game theory view, we show that the efficient outcome is fully implementable in U-SPNE. In Farsighted Stable Sets in Hotelling’s Location Games, we apply Farsighted Stable Set (FSS) to Hotelling’s linear and circular location games. It is shown that there always exists an FSS which consists of location profiles yielding equal payoff to all players. While this FSS is unique when the number of players is two, uniqueness no longer holds for both models when the number of players is at least three. We prove the existence of other types of FSSs and provide possible interpretations from the viewpoint of players’ bargaining power.Ph. D.Includes bibliographical referencesby Junnosuke Shin