通貨替代、貿易彈性與實質匯率動態

Currency Substitution, Trade Elasticities, and Real Exchange Rate Dynamics

曹添旺(Tien-Wang Tsaur) ； 黃俊傑(Chun-Chieh Huang)

《經濟論文》 33卷2期 (2005/06) Pp. 173-200

https://doi.org/10.29628/AEP.200506.0002

摘要

本文設立一個具個體最適化基礎的通貨替代模型，據以分析小型開放經濟實質匯率的動態調整型態。研究的結果發現：若Marshall-Lerner條件成立，則實質匯率的調整有唯一的馬鞍路徑。反之，若Marshall-Lerner條件不成立，則實質匯率可能呈現發散或不確定的調整。在Marshall-Lerner條件不成立的情況下，若國外通貨增長率為零，則動態體系勢必發散。再者，若國外通貨增長率為正，且通貨替代彈性等於握有通貨的成本彈性時，當通貨替代彈性小於某定值時，體系會發散；當通貨替代彈性較大時，實質匯率會發生不確定的調整。最後，若通貨替代彈性不等於握有通貨的成本彈性，則通貨替代彈性與貿易彈性的相對大小主導實質匯率的調整型態。

關鍵字

通貨替代 ； 不確定性 ； 貿易彈性 ； 匯率動態

並列摘要

This paper studies the dynamic pattern of real exchange rates in a currency substitution model with optimized microfoundation. It shows that when Marshall-Lerner condition holds, the adjustment of real exchange rates has a unique saddle path. On the contrary, when the Marshall-Lerner condition does not hold, the adjustment of real exchange rates may be either unstable or indeterminate. Under the situation where the Marshall-Lerner condition fails, if the foreign monetary growth rate is zero, the dynamic system will be unstable. Moreover, if the foreign monetary growth rate is positive, and the currency substitution elasticity is equal to the cost elasticity of holding currency, then the dynamic system is unstable while the currency substitution elasticity is smaller than a certain constant value, and the adjustment of real exchange rates is indeterminate while the currency substitution elasticity is larger. Finally, if the currency substitution elasticity is unequal to the cost elasticity of holding currency, the relative magnitude between currency substitution elasticities and trade elasticities determines critically the dynamic properties of real exchange rates.

並列關鍵字

Currency substitution ； Indeterminacy ； Trade elasticities ； Exchange rate dynamics

參考文獻

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