Affiliation: | (1) Faculty of Economics, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachiohji, Tokyo 192-0397, Japan (e-mail: kijima@bcomp.metro-u.ac.jp), JP;(2) Graduate School of Economics, Osaka University, 1-7 Machikaneyama-machi, Toyonaka, Osaka 560-0043, Japan (e-mail: ohnishi@econ.osaka-u.ac.jp), JP |