经济政策有效性的理论分析* ——以货币政策为例

本文在更一般的不完全信息情形下，以货币政策为例，分析了经济政策的时间不一致问题。结果表明，当私人部门与政府部门存在不对称信息，政府部门具有信息优势时，最优经济政策与私人部门所持有的关于经济状态的信念有关。从福利的角度看，当现实经济状态对经济政策灵敏时，政府部门有公开经济状态信息的激励；反之，政府部门则有隐瞒经济状态信息的激励。因此，在市场经济的顶层设计中，除政府部门需要建立相关经济决策咨询机构外，还要推动独立的民间智库发展，使公众逐步摆脱信息劣势。

A THEORETICAL ANALYSIS ON THE EFFICIENCY OF ECONOMIC POLICY——Taking Monetary Policy as an Example

This paper extends Kydland and Prescott s classical model of time inconsistent monetary policy to a more general case in which the government and private sector have asymmetric information on the economic state. The equilibrium outcomes show that an efficient economic policy has to take the private sector s belief on economic state into account. From the perspective of social welfare, policy maker has an incentive to disclose the information on economic state to private sector when the economic state is relatively sensitive to the policy. Some related policy suggestions are provided in this paper.