本文探究一小型開放經濟體系之貨幣當局,當經濟體系受到生產技術之實質衝擊後,執行不同貨幣政策目標,並採行不同程度的資本管制手段,相關總體變數到底會產生何種衝擊反應。有別於一般文獻只在資本完全移動或完全不移動下探討實質的衝擊反應,我們引進Benigno(2001,2007)所發展的交易成本概念,建立資本不完全移動之小型開放經濟模型。根基於Gali and Monacelli(2005)的新凱因斯理論架構,本文建立的理論模型,因資本移動不完全所形成的國際資本市場結構,可推導出具應時變動風險貼水之未拋補的利率平價。並依據理論模型,分別刻劃模擬出資本移動程度的改變,在貨幣當局採行穩定國內通貨膨脹、穩定消費者物價指數通貨膨脹、以及穩定名目匯率之不同政策目標下,實質衝擊對總體變數的動態影響。我們的研究顯示,當國際資本市場完全時,(實質及名目)匯率與通貨膨脹率間、通貨膨脹率與產出缺口間,以及(實質及名目)匯率與產出缺口間,均具有明顯的抵換關係;但是,考慮國際間資本不完全移動所造成資本市場不完全,本文的結論隱含,貨幣當局可以配合貨幣政策目標,透過適度的管制資本移動手段,減緩上述的抵換關係。
We present a small open economy with a Benigno's (2001, 2007) version of incomplete international asset market based on the new Keynesian story, and show how the equilibrium dynamics can be reduced to a representation in domestic inflation and the output gap. We use the resulting framework to analyze the macroeconomic implications of three alternative monetary policy targets for a small open economy against the incomplete international asset market: (a) a domestic inflation targeting policy, (b) a CPI inflation targeting policy, and (c) exchange rate pegs. The main findings of this study are as follows: In the presence of imperfect capital mobility, stabilization of domestic inflation, output gap, and exchange rate are trade-offs to each other. The monetary authority maymoderate the trade-off relationship through appropriate capital control. In addition, when capital mobility is perfect, the trade-off relationship emphasizedby Gali and Monacelli (2005) still holds.