1. Department of Economics, Washington University in St. Louis, Campus Box 1208, St. Louis, MO 63130-4894, and European University Institute, Italy (e-mail: )
2. Facoltà di Economia, Università di Palermo, Viale delle Scienze 90128, Palermo, Italy (e-mail: )
3. Universidad de San Andrés, Vito Dumas 284 (B1644BID) Victoria, Provincia de Buenos Aires, Argentina and National Scientific and Technical Research Council (CONICET) (e-mail: )
4. Instituto de Economía, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, Chile (e-mail: )