新凯恩斯模型下我国法定存款准备金政策理论研究

Theoretical Research on China’s Legal Required Reserve Policy in the New Keynesian Model

我国央行较为频繁使用法定存款准备金政策调控信贷及货币量,“泰勒法则”并不能较好刻画我国的利率法则。在利率并轨改革和利率市场化转型背景下,本文构建了一个修正的新凯恩斯模型,基于我国目前的市场状况,该模型加入新变量货币乘数,该变量受利率和法定存款准备金率的影响。在中央银行采用相机抉择的货币政策假定下,本文通过最优化问题进一步求解理论最优的利率和理论最优的存款准备金率路径,假设利率和存款准备金率是中央银行可以在每一期自行调整的变量,通过求解含有约束条件的最优化问题,可得理论最优利率和理论最优存款准备金率。本文关注央行对法定存款准备金率的三种前瞻性选择,即上调、下调及不调整,通过Probit模型构建最优法定存款准备金率与央行现行准备金率间的合理差值区间。

China’s central bank uses the legal required reserve policy more frequently to regulate credit and money supply,while the Taylor rule does not provide a good picture of the rule of interest rate in China.In the context of the reform for the combination of interest rates and market transformation of interest rate,this article constructs a modifi ed New Keynesian model with a new variable,money multiplier,which is influenced by interest rate and legal reserve requirement ratio,based on the current market conditions in China.Under the assumption that the central bank adopts the monetary policy with discretionary approaches,this article further seeks solutions for the theoretically optimal interest rate and the theoretically optimal reserve requirement ratio with an optimized problem.This article assumes that the interest rate and the reserve requirement ratio are variables that the central bank can adjust by itself in each period,and then the theoretically optimal interest rate and the theoretically optimal reserve requirement ratio are obtained by solving the optimized problem containing constraints.This study focuses on three forward-looking options for the central bank’s legal reserve requirement ratio,i.e.upward adjustment,downward adjustment and no adjustment,and constructs a reasonable range of diff erences between the optimal legal reserve requirement ratio and the central bank’s current reserve requirement ratio by the Probit model.