1. Graduate School of Economics, Hitotsubashi University. 2-1 Naka Kunitachi, Tokyo 186-8601, Japan yoichi.sugita@r.hit-u.ac.jp
2. Institute of Economic Research, Hitotsubashi University. 2-1 Naka Kunitachi, Tokyo 186-8601, Japan kensuke-teshima@ier.hit-u.ac.jp
3. ITAM. Av. Santa Teresa # 930, Mexico, D. F. 10700 enrique.seira@itam.mx