Portfolio models and planning for export diversification: Malawi, Tanzania and Zimbabwe
研究了投资组合方法在出口收益多元化中的优缺点，并用马拉维、坦桑尼亚和津巴布韦的数据展示其应用，提出了更适合发展中国家的改进模型，帮助政策制定者同时提高出口收益并降低波动。
Evidence is presented regarding strengths and limitations of portfolio approaches as applied to diversifying export earnings. An empirical application using data from Malawi, Tanzania, and Zimbabwe is used to demonstrate these strengths and limitations. Modifications of the typical portfolio approach to export diversification are presented; these modifications help make the approach more plausible for use in developing countries. The modified approach is shown to provide guidance to policymakers who seek simultaneously to increase export earnings and reduce their instability.