First Author:   Hironori Otsubo Soka University ootsubo@soka.ac.jp   Soka University Faculty of Economics, 1-236 Tangi-machi Hachioji, 192-8577, Japan   +81 (0)42 691 9316(Phone) +81 (0)42 691 9316(Fax) http://home.soka.ac.jp/~ootsubo/