Incentives and institutions: essays in mechanism design and game theory with applications

摘要

In the first part of this dissertation we study the problem of designing desirable mechanisms for economic environments with different types of informational and consumption externalities. We first study the mechanism design problem for the class of Bayesian environments where preferences of individuals depend not only on their allocations but also on the welfare of other individuals. For these environments, we fully characterize interim efficient mechanisms and examine their properties. This set of mechanisms is compelling since interim efficient mechanisms are the best in the sense that there is no other mechanism which generates unanimous improvement. For public good environments, we show that these mechanisms produce the public good closer to the efficient level of production as the degree of altruism in the preferences increases. For private good environments, we show that altruistic agents trade more often than selfish agents.We next consider mechanism design problem for matching markets where externalities are present. We present mechanisms that implement the core correspondence of many-to-one matching markets, such as college admissions problems, where the students have preferences over the other students who would attend the same college. With an unrestricted domain of preferences the non-emptiness of the core is not guaranteed. We present a sequential mechanism implementing the core without any restrictions on the preferences. We also show that simple two-stage mechanisms cannot be used to implement the core correspondence in subgame perfect Nash equilibrium without strong assumptions on agents' preferences.In the final part of the dissertation we focus on another matching market, one-to-one assignment games with money. We present an alternative way to characterize the core as the fixed points of a certain mapping. We also introduce the first algorithm that finds all core outcomes in assignment games. The lattice property of the stable payoffs, as well as its non-emptiness, are proved using Tarski's fixed point theorem. We show that there is a polarization of interests in the core by using our formulation.