This paper analyzes portfolio diversification, leverage, and financial contagion. It studies the extent to which basic principles of portfolio diversification explain “contagious selling” of financial assets when there are purely local shocks. The paper demonstrates that the elementary portfolio theory offers key insights into “contagion.” Most important, portfolio diversification and leverage are sufficient to explain why an investor will find it optimal to significantly reduce all risky asset positions when an adverse shock impacts just one asset.

This paper provides an overview of the recent theoretical and empirical research on herd behavior in financial markets. It looks at what precisely is meant by herding, the causes of herd behavior, the success of existing studies in identifying the phenomenon, and the effect that herding has on financial markets. The paper also surveys a selected number of studies that evaluated the demand for money using the error-correction model approach in the 1990s across a range of industrial and developing countries.

This paper discusses the origins of the pyramid schemes and the way the authorities handled them. The paper analyzes the economic effects of the pyramid schemes, concluding that despite the descent into anarchy triggered by the schemes’ collapse, their direct effects on the economy are difficult to specify and appear to have been limited. The paper also argues that prevention of pyramid schemes is better than cure and that government and international financial institutions should be vigilant in clamping down on frauds.

This paper presents a broad overview of postwar analytical thinking on international macroeconomics, culminating in a more detailed discussion of recent progress. The paper reviews important empirical evidence that has inspired alternative modeling approaches, as well as theoretical and policy considerations behind developments in the field. The paper presents an empirical study of fiscal policy in countries with extreme monetary regimes. It also examines members of multilateral currency unions, dollarized countries that officially use the money of another country, and countries using currency boards.

This paper analyzes the link between product variety and economic growth. It finds support for the hypothesis that a greater degree of product variety relative to the United States helps to explain relative per capita GDP levels. The paper presents an empirical study for South Africa, which indicates that there exists a stable money demand type of relationship among domestic prices, broad money, real income, and interest rates, as well as a long-term relationship among domestic prices, foreign prices, and the nominal exchange rate.

This paper examines sources of economic growth in East Asia. The conventional growth-accounting approach to estimating the sources of economic growth requires unrealistically strong assumptions about either competitiveness of factor markets or the form of the underlying aggregate production function. The paper outlines a new approach utilizing nonparametric derivative estimation techniques that does not require imposing these restrictive assumptions. The results for East Asian countries show that output elasticities of capital and labor tend to be different from the income shares of these factors. The paper also explores the compensating potential of private intergenerational transfers.

This last issue for 2005 comprises seven new papers, including a contribution to the journal's occasional Special Data Section about domestic debt markets in Sub-Saharan Africa, and also an in-depth look at the internal job market for entry-level economists at the IMF. The remaining articles cover toics as diverse as: modeling of asset markets, exchange rates in developing countries, international bank claims on Latin America, the effectiveness of "early warning" systems, and the use (by emerging market countries) of the IMF's Special Data Dissemination Standard (SDDS).