曼昆宏观经济
P312
有详细的解释
The Mundell–Fleming model makes one important and extreme assumption:
it assumes that the economy being studied is a small open economy with
perfect capital mobility.That is, the economy can borrow or lend as much as it
wants in world financial markets and, as a result, the economy’s interest rate is
determined by the world interest rate. One virtue of this assumption is that it
simplifies the analysis: once the interest rate is determined, we can concentrate
our attention on the role of the exchange rate. In addition, for some
economies, such as Belgium or the Netherlands, the assumption of a small
open economy with perfect capital mobility is a good one.Yet this assumption—
and thus the Mundell–Fleming model—does not apply exactly to a
large open economy such as the United States. In the conclusion to this chapter
(and more fully in the appendix), we consider what happens in the more
complex case in which international capital mobility is less than perfect or a
nation is so large it can influence world financial markets