Research On The Implementation Characterizations Of Social Choice And Applications Of Implementation Mechanisms

As the rapid development of economy and further deepening of institutional reform, setting up institutions up to economic and social development level and consummating the entire institution system have been more and more recognized by people of estates. But in the process of implementation, the effects of many institutions and laws are discounted by strategic behaviors of individuals. To make sure that institutions don't deviate from their designed goals, it is necessary to consider the strategic behaviors of individuals. So offering some theories and methods which can check the implementability of a goal to guide the design of institutions is in great need. Therefore, the study on implementation theory is of great significance both in theory and practice.The dissertation investigates the implementability of social choice rules in four kinds of environments, including Bayesian implementation, Nash implementation with cost of signal, implementation when the planner is a player, and voluntary implementation when the planner is a player. Optimal allocation of pollution and defense procurement entry rights is also discussed.The dissertation investigates the implementable characterization of Bayesian implementation in general environment. The result shows that in general environment:(i) if the number of agents is no less than 2, any incentive compatible social choice function set satisfying A+ condition is Bayesian implementable; (ii) if the number of agents is 2, any incentive compatible social choice function set satisfying monotonicity intersection unanimity condition is Bayesian implementable and any Bayesian implementable social choice function set satisfies monotonicity intersection condition; (iii) if the number of agents is more than 2, any incentive compatible social choice function set satisfying monotonicity no-veto unanimity condition is Bayesian implementable.By introducing the cost of signal in implementation, the dissertation investigates implementable characterization of Nash implementation with cost of signal. The result shows that in environment with moral constraint, if the number of agents is more than 2, any social choice correspondence satisfying unanimity condition is Nash implementable, and if the number of agents is 2, any social choice correspondence satisfying unanimity condition and intersection condition is Nash implementable.The dissertation also investigates implementable characterization of implementation in incomplete information environment when the planner is a player. It proves that:when the planner selects an outcome after she has seen the signal profile of agents, a social choice function set is interactive implementable in FGP equilibrium if and only if it satisfies reliable monotonicity condition and y condition.The dissertation investigates implementable characterization of voluntary implementation when the planner is a player. The result shows that in complete information environment:(i) if the number of agents is more than 2 and the planner is a player, a social choice correspondence is voluntary implementable if and only if it satisfies G reliable monotonicity condition; (ii) if the number of agents is 2 and the planner is a player, a social choice correspondence is voluntary implementable if and only if it satisfies G reliable monotonicity condition and G intersection condition.The dissertation investigates implementation problem of pollution allocation and allocation of defense procurement entry rights. It designs a mechanism, modified Duggan mechanism, to implement the optimal allocation of pollution and proves that the equilibrium outcome of modified Duggan mechanism can reach the optimal allocation of pollution. The dissertation also designs a mechanism, analogous Vickrey mechanism, to implement the optimal allocation of defense procurement entry rights and proves that even the technology level of a manufacturer is its private information, analogous Vickrey mechanism can also implement the optimal allocation of defense procurement entry rights.Finally, the dissertation makes a summary of work, and brings forwards some directions for future research.