1. The World Bank, 1818 H Street, Washington, DC 20433.
2. Tuck School, Dartmouth College, 314 Woodbury Hall, Hanover, NH 03755.
3. EDHEC Business School, 393 Promenade des Anglais BP 3116, 06202 Nice Cedex 3, France.
4. Department of Economics, Harvard University, Littauer Center M-9, Cambridge, MA 02138.