在本論文中，我們回顧了5種實證上常使用的單根檢定方法並且利用其來檢驗經常帳的跨期平衡理論是否會成立。實證結果顯示，就台灣而言，ADF (1979) 與 Zivot and Andrews (1992) 的單根檢定結果支持經常帳具有跨期平衡，然而 Phillips and Perron (1988)、Lee and Strazicich (2004)單一結構性改變點與 Lee and Strazicich (2003)二個結構性改變點的單根檢定結果並不支持經常帳跨期平衡理論；而韓國的實證結果發現，不論是實質經常帳或是經常帳佔GDP的比率，5種單根檢定幾乎都不支持經常帳具有跨期平衡。台灣與韓國的經常帳不具有跨期平衡的特性，可能的原因為台灣與韓國都是經常帳持續有大量盈餘的國家，因此累積了大量的外匯準備，由於經常帳尚未到達向下調整的階段，導致跨期平衡不成立。 In this paper, we review the five different kinds of unit root test methods, which frequently used in the empirical studying, to test whether the current account satisfy the expected intertemporal balance.The empirical results show that base on the unit root test methods suggested by ADF (1979) and Zivot and Andrews (1992), they support the current account of intertemporal balance in Taiwan case studying. However, according to the unit root test of Phillips and Perron (1988), Lee and Strazicich (2004), and Lee and Strazicich(2003), the current account does not support the intertemporal equilibrium theory; In the case of South Korea, the empirical results show that current account do not support the intertemporal balance theory regardless of the real term or as the ratio of GDP. Why Taiwan and South Korea's current account does not support the intertemporal balance? We reckon that currently Taiwan and South Korea have large surplus of current account. Because the current account have not yet reached the stage of downward adjustment, they lead to the violation of intertemporal equilibrium.
