蒙代尔-弗莱明模型的扩展与人民币汇率动态

Extension of Mundell-Fleming Model and RMB Exchange Rate Dynamics

本文回顾了关于人民币汇率的几次大讨论,揭示了国际收支失衡背后的国际货币体系因素。针对蒙代尔~弗莱明模型不适合分析人民币汇率和国际收支失衡的现象,本文将蒙代尔-弗莱明模型扩展成一个两国模型,发现汇率与利率和收入之间存在的非线性关系能为国际收支和汇率长期失衡提供一种理论解释,大国应该采取浮动汇率制并有必要加强宏观政策协调。本文还用向量误差修正模型估计了人民币名义有效汇率和对美元汇率,发现当前两种汇率都处于高估状态,在未来一段时间人民币汇率有向下调整的压力。

This paper reviews several controversies over RMB exchange rates,and reveals the international monetary system background of persistent imbalances of international payments.In connection with that the situation that MundellFleming model,designed for a single small economy under Bretton Woods System,is no longer relevant to analysing RMB exchange rate and imbalances of international payment,this paper extends Mundell-Fleming model to the one that includes two big countries,and finds that there is a nonlinear relationship among exchange rates,interest rates and income of two countries,which can provide another theoretical explanation for the deviation of exchange rate from its baseline and imbalances of international payment.Moreover,the paper believes that it is necessary to adopt flexible exchange rate regime and strengthen coordination of macroeconomic policies between big countries.Using the VEC model,this paper estimates both RMB nominal effective exchange rate and RMB-USD exchange rate,finding that both are currently overvalued and may experience depreciation for some time in the future.