the mission of The World Bank Economic Review is to encourage and support research in the field of development economics. We seek to publish and disseminate innovative theoretical and empirical research that identifies, analyzes, measures, and evaluates the macro and micro-economic forces that promote or impede economic development with a view towards providing the knowledge necessary for designing, implementing, and sustaining effective development policies in low and middle income countries. Our intended audience comprises a worldwide readership of economists and other social scientists in government, business, international agencies, universities, and research institutions.