First Author:   Chiaki Hara Institute of Economic Research, Kyoto University hara@kier.kyoto-u.ac.jp   Yoshida-Honmachi, Sakyo-ku Kyoto, 606-8501, Japan   +81 (0)75 753 7149(Phone) +81 (0)75 753 7149(Fax) http://www.kier.kyoto-u.ac.jp/~hara/