POLITICAL RISK AND THE BENEFITS OF INTERNATIONAL PORTFOLIO DIVERSIFICATION.

This paper examines the benefits of portfolio investment in the stock markets of politically risky countries by evaluating the effects of political risk constraints on the performance of a portfolio of international stocks. We use monthly data on political risk ratings and stock returns for a sample of thirty-six countries from April 1982 to December 1991, Ex-post and ex-ante portfolio selection strategies are developed to assess the gains from international diversification. Efficient sets are derived using a quadratic programming technique. We use four ex-ante portfolio strategies whose optimal portfolio weights are those of the equally weighted portfolio, the minimum-variance portfolio, the certainty-equivalence tangency portfolio and the Bayes-Stein portfolio. The empirical findings, based on the performance tests of Jobson and Korkie [1981], suggest that diversification among politically risky countries improves the risk-return characteristics of optimal portfolios. However, the most striking benefit of the inclusion of politically risky countries in an international portfolio is the reduction in overall portfolio risk. [ABSTRACT FROM AUTHOR]