First Author:   Daisuke Oyama Graduate School of Economics, Hitotsubashi University oyama@econ.hit-u.ac.jp   Graduate School of Economics, Hitotsubashi University, Naka 2-1 Kunitachi, 186-8601, Japan       http://www.econ.hit-u.ac.jp/~oyama/ Second Author: Satoru Takahashi Department of Economics, Princeton University satorut@princeton.edu   Princeton University Princeton, 08544, USA       http://www.princeton.edu/~satorut/