在此篇論文中我們考慮連續時間架構下, 加入匯差風險與利率風險之跨國投資組合問題. 延續 Lioui, Poncet (2003) 的研究架構, 我們考慮
國內外債券股票與現金的投資組合, 以martingale方法求解避險操作與最佳投資策略.

In this study, we investigate the hedge demands in international portfolio management under a general continuous time framework for constant relative risk averse
investors where, in particular, exchange rate risk and the interest rate risk are incorporated. Within this international economy, the changes of real exchange rates, real interest rates and stock prices are assumed to follow the Markovian processes whose drifts and diffusion parameters are driven by certain state variables. Our approach is through the use of the martingale methodology developed by Cox and Huang (1989, 1991) as proposed in the work of Lioui and Poncet (2003). Following their framework, we consider the economy of the investors that consists of one foreign currency and the domestic one, together with their bond portfolios and stock indices. Adding to the previous works, we have compared the obtained optimal strategies with some prevailing ad hoc ones in order to clarify the hedge effects in financial decision from the long term perspective.

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