환위험프리미엄은 그 존재 및 결정요인을 찾기 위한 연구로 발전되어 왔는데 크게 국제 포트폴리오 밸런스 접근법, 시간가변적 행태분석을 통한 접근법, 주식시장 접근법으로 나눌 수 있다. 이 중 주식시장 접근법은 외환시장이 국내 및 해외주식시장과 상호 관련되어 있어 한 시장에서 확인된 위험요인은 다른 시장의 위험과도 연관될 수 있다는 가정에서 출발하고 있다. 본 연구는 주식시장 접근법을 근간으로 Chiang(1991)의 국제자산평형조건(IAP: International Asset Parity Condition)을 이용함으로써 주식시장에서 추출한 자국 및 외국의 주가위험요인들이 환위험프리미엄을 설명하고 있는지를 밝히고자 하였다. 아울러, 환위험프리미엄과 주가위험요인들간의 여러 가지 영향관계를 추가적으로 살펴보고 Chiang의 IAP 공식의 타당성 여부도 살펴보고자 하였다. 요인분석 및 회귀분석을 사용하여 실증분석을 수행한 결과, 환위험프리미엄은 두 국가 각각에서 추출된 다수의 일반화된 주가위험요인들과 통계적으로 유의한 영향관계를 형성하고 있는 것으로 나타났다. 추가적으로, 자국 또는 외국의 주가위험요인들은 자국통화표시 환위험프리미엄과 국가마다 상이한 영향관계를 형성하고 있다는 것과 통계적으로 유의하게 나타난 자국의 주가위험요인들은 자국통화표시 환위험프리미엄과 항상 동일한 부호의 영향관계를 나타낸다는 것을 알 수 있었다. 또한, 자국과 주요국 통화간 선도프리미엄(forward premium)들이 자국의 주가위험요인들과 하나 이상의 경우에서 유의한 결과를 보여줌으로써 IAP의 전제조건, 즉 주가위험요인들이 선도프리미엄 정보를 포함하고 있다는 주장이 타당함을 간접적으로 보여 주고 있다.
The notion of exchange risk premium has derived from the study to test the efficiency of foreign exchange market. By replacing the risk-neutral hypothesis to the risk-averted hypothesis, exchange risk premium is considered as compensation for the market participants in return for bearing the risk of future spot exchange rate uncertainty. Under this hypothesis, forward rate has a systematic difference with the future spot rate. On the other hand, exchange risk premium is derived from developing the portfolio balance model of the determination of the equilibrium exchange rate. The portfolio balance model postulates that domestic and foreign bonds are imperfect substitutes, such that ‘International Fisher Effect(IFE)’does not hold. Therefore, exchange risk premium is related to the relative share of that country’s assets which make up the overall portfolio. That is, exchange risk premium is the value subtracting the differences of nominal interest rate between domestic and foreign bonds from exchange rate change. Considering interest rate parity theorem, two different approach on exchange risk premium explained above produce the same value.Three approach have been developed to explain exchange risk premium. First, there is the international portfolio balance approach proposed by Dornbusch(1983) and Frankel (1982, 1986). This approach has its roots in the imperfect bond substitution and recognizes exchange risk premium as a compensation for holding a greater share of a particular country’s assets. However, testing the model in several major foreign exchange markets found that the risk-neutral hypothesis cannot be rejected by the data. The second approach was to invoke a time-varying parameter methodology. Fama(1984), for example, tries to explain time varying risk premium in the foreign exchange market. However, no concrete evidence has been given that a significant relationship exists between exchange risk premium and risk factors and the results was limited to relying on econometrical approach. The third approach, due to Robicheck and Eaker(1978), Giovannini and Jorion(1987) and most recently, Chiang(1991) has been to relate the foreign exchange market risk premium to the stock market excess returns. This approach assumes that the foreign exchange markets and equity markets are interrelated such that the risk premium identified in one market may be related to the risk or excess return in another. For example, Chiang(1991) used International Asset Parity(IAP) Condition to theoretically derive the equation explaining exchange risk premium with domestic and foreign equity risk premia.This paper addresses whether domestic and foreign equity risk premia, based on the IAP equation, are the decision factors to explain the exchange risk premium. and how the foreign exchange market risk premium and the stock market risk premia are interrelated. Behavioral relationships between exchange risk premium and equity risk premia and additional empirical analysis on the validity of IAP will be discussed.First of all, APT model was applied to IAP equation in place of the equity return to explain exchange risk premium with domestic and foreign equity risk premia. Efforts have been made to test whether the exchange risk premium of the 5 developed countries(US, UK, Japan, Canada, Germany) can be actually explained by domestic and foreign equity risk premia. As a result of the empirical test using factor analysis and regression analysis, exchange risk premium is explained by several domestic and foreign equity risk premia, which are statistically significant. Additional results about exchange risk premium revealed from the test were, firstly, the domestic and foreign equity risk premia do not always influence exchange risk premium simultaneously. Secondly, each domestic equity risk premium that is statistically significant displays identical sign as the domestic currency dominated exchange risk premia in all case. A further study on the validity of International Asset Parity reveals that each equity risk premium in one country is sensitive to the domestic currency dominated forward premium of the other four countries. As a result, forward premium variables remain as the independent variables explaining the equity risk premia, and this evidence indirectly supports the validity of the model derived from this paper.