1. School of Industrial and Labor Relations, Cornell University, 265 Ives Hall, Ithaca, NY 14853, and NBER and CESifo.
2. School of Industrial and Labor Relations, Cornell University, 264 Ives Hall, Ithaca, NY 14853, and CESifo.
3. School of Industrial and Labor Relations, Cornell University, ILR Graduate Student Mailboxes, Ives Hall, Ithaca, NY 14853.
4. Faculdade de Economia, Administracao e Contabilidade, University of Sao Paulo, Avenida Professor Luciano Gualberto, 908, Cidade Universitaria, Predio FEA 1, Sao Paulo, SP 05508, Brazil.