次贷危机冲击、政府反应和人民币汇率

The Shock of Subprime Crisis,Government Response and RMB Exchange Rate

本文结合政府损失函数的汇率超调模型,解释了为何人民币对美元汇率在次贷危机中又恢复到"实际的"盯住单一货币的汇率制度。本文认为,一方面由于危机冲击使得汇率波动的成本在政府损失函数中的权重增加,另一方面政府为应对冲击而出台的经济刺激政策,抵消了冲击的负面影响。本文进而认为,不同汇率制度的选择实际上源于对赋予不同目标以不同的权重的政府损失函数进行最优化的结果。本文观点同样可对东南亚金融危机后的人民币汇率转向盯住单一货币的汇率制度做出解释。

Using Dornbusch overshooting model married with a government loss function, this paper explains why USD/ RMB exchange rate actually turns back to an arrangement of De facto pegging against single currency in the subprime credit crisis. Our conclusion is that on the one hand this is caused by a larger cost weight of exchange rate fluctuations in the government loss function, on the other hand it is caused by the stimulus polices taken to counteract the crisis. We further conclude that which exchange rate regime is taken actually depends on the optimized result of government loss function with different targets given different weight. Our conclusion can also be brought to explain why RMB exchange rate turned to peg against USD after the Southeast Asia financial crisis.