First Author:   Ryo Hashizume Faculty of Economics, Daito Bunka University rhashizume@ic.daito.ac.jp         Second Author: Takeshi Ikeda Faculty of Economics, Daito Bunka University ikeda@ic.daito.ac.jp         Third Author: Tatsuhiko Nariu Graduate School of Business, Doshisha University tnariu@mail.doshisha.ac.jp