Discussion: The Exposure of Long-Term Foreign Currency Bonds
讨论外币资产的实际购买力受汇率影响，分析购买力平价和国际费雪效应是否消除汇率风险，指出这些关系仅长期平均成立，因此外币资产对国内投资者仍有更高收益波动，需通过投资组合等因素解释其持有动机。
The unique characteristic of a foreign asset is that the real purchasing power of the cash flows from the asset depends on the exchange rate prevailing on the conversion date. A naive view is that this dependence exposes foreign assets to exchange risk proportional to the volatility of the exchange rate and, other things equal, makes foreign assets much riskier than domestic ones. Anothe extreme is that for nonmonetary foreign assets, purchasing power parity (PPP) causes exchange rates to move inversely todifferential inflation rates, thereby eliminating exchange risk. Aliber and others maintain that a similar argument applies to foreign monetary assets. The international Fisher effect (IFE) causes the exante equilibrium return on all default-free monetary assets, measured in the domestic currency, to be the same regardless of the currency denomination of the instrument. The fact is, however, that PPP and IFE cannot be expected to hold instantaneously throughout time, but only on average over time. Consequently, although foreign assets may promise the same expected return as domestic assets, they will have a higher variance of return as seen by domestic investors. To justify the holding of foreign assets by a domestic investor, one must introduce portfolio considerations, the possibility of consumption expenditures denominated in the foreign currency, heterogeneous expectations, or market imperfections.