本文係以Frenkel and Rodriguez(1982)與Sutherland(1995)的模型為基礎，從而建構一隨機性的開放總體經濟模型，在本國商品與外國商品並非呈現完全替代導致購買力平價說無法成立、本國債券與外國債券也並非呈現完全替代導致資本呈現不完全移動的前提下，運用傳統隨機微分方程式解法(stochastic differential equations)，來探討當經濟體系面臨商品支出面的隨機性干擾時，貨幣當局施行匯率目標區政策，是否具安定相關總體經濟變數的效果。結果發現（註1）： 1.當經濟體系面臨商品支出面的隨機性干擾時，匯率目標區政策的施行，對相關總體經濟變數是否具有安定效果與是否可解釋Kempa and Nelles(1999)所觀察到的匯率與利率水準兩者變動方向呈現正相關的實證結果其中「資本移動程度相對大小」這個決定因素雖然與既存文獻相同都占了舉足輕重的角色，但在對相關總體經濟變數是否具有安定效果上仍有很大的不同。 2.一旦民眾面對匯率目標區持續維持抑或重整的不確定政策時，匯率目標區政策的施行，對相關總體經濟變數是否具有安定效果？其中「資本移動程度相對大小」與「民眾預期貨幣當局將會進行重整比例的大小」這兩個重要因素都占了關鍵樞紐的角色，而「資本移動程度相對大小」這個決定因素在判定是否可解釋Kempa and Nelles(1999)所觀察到的匯率與利率水準兩者變動方向呈現正相關的實證結果上也占了舉足輕重的角色。事實上，「資本移動程度相對大小」這個重要因素則是既存文獻在分析相同主題時所忽略掉的關鍵性重要決定因子。

This paper extends the theoretical framework of Frenkel and Rodriguez (1982), Sutherland (1995) model to policy uncertainty case. In a stoachastic open macroeconomic model is characterized by purchasing power parity postulate which dosen't hold and imperfect capital mobility, we use the Lai's et al. (2001) ”new graphical approach” to interprate if a country is faced with stoachastic disturbance of commodity expenditure and the monetary authority adopts the ”exchange rate target zones” policy, what will be the effect of these disturbances on the possible honeymoon effect of relevant macroeconomic variables? The major finding are (1)if the monetary authority will execute the target zone policy definitely, the capital mobility degree is larger (smaller), the exchange rate and output (exchange rate, interests rate and price) will own the honeymoon effect, but the interests rate and price (output) won’t. Additionally we can't (can) explain the positive empirical relationships between the exchange rate and interests rate which was observed by Kempa and Nelles (1999) (2) if the monetary authority perhaps maintains the target zone policy or realigns the central parity of exchange rate, the local people are faced with this uncertain policy, the relative magnitude of capital mobility degree and the probability of local people expected the monetary authority will realign the central parity of exchange rate are the key factors to determine whether the exchange rate, interests rate, price and output own the honeymoon effect or not? The relative magnitude of capital mobility degree is the main factor to determine whether we can explain the positive empirical relationships between the exchange rate and interests rate which was observed by Kempa and Nelles (1999).