一般均衡中的利率、确定性与最优规则

利率规则理论是以短期利率作为货币政策工具而发展起来的一套新的理论,它体现了货币经济学家在货币政策领域内的新的尝试和努力。在利率规则理论中,货币经济学家试图解决两个问题:利率规则冲击对非政策经济变量的短期影响是什么,以及一个好的利率规则应当具有怎样的性质。利率规则将短期利率作为非政策经济变量的内生反应函数,使得货币经济学家可以在一般均衡模型中探讨这两个问题。然而,由于利率规则从一开始就是出于一种偏好的设定,因此,讨论的结果并不符合稳健性和科学性的要求,这就削弱了理论预言的可靠性。在某种意义上,利率规则理论若想成为一门真正的"科学的艺术",它就必须为内生利率规则寻找到一个坚固的微观基础。本文梳理评述了利率规则理论在经验上和理论上的成就和不足。

Interest-rate, Determinacy and Optimal Rules in General Equilibrium

This thesis discusses the empirical and theoretical achievements and defects of interest rate rules theory.Interest-rate rules theory,which views short-term interest rate as monetary policy instrument,reflects the new ideas and efforts of monetarists engaged in monetary policy.Two problems have to be resolved in this theory,that is,"what effects does an interest rate policy shock have on non-policy variables?" and "what is characteristic of a good interest-rate rule?" A typical interest-rate rule means that short-term interest rate is an endogenous feedback function of non-policy variables,so that the problems can be analyzed in the framework of general equilibrium models.However,the results of discussion do not satisfy the criterion of robustness and science,because of interest rate rules being predetermined by individual preferences of monetarists.As a result,the reliability of the conclusions deduced from the assumption that interest rate is an endogenous feedback function of non-policy variables is impaired.In a sense,until endogenous interest-rate rules find out a firmer micro-foundation for themselves,'art of science' does not fall on the shoulders of interest-rate rules theory.