1. Leonard N. Stern School of Business, New York University, Tisch Hall, 40 West 4th Street, Room 9-09, New York, NY 10012.
2. Department of Economics, University of California-Berkeley, 501 Evans Hall, Berkeley, CA 94720-3880.
3. HEC Paris, 1 rue de la libération, 78351 Jouy-en-Josas, France, and Centre for Economic Policy Research.