Taro Ikeda Graduate School of Economics Kobe University, 2-1 Rokko-dai, Nada, Kobe, 657-8501, Japan   7-5-19-308 Shinohara-minamimachi, Nada, Kobe, Hyogo 657-0059 Japan   young_tubo80@msn.com             JEL Areas: E : Macroeconomics and Monetary Economics E1 : General Aggregative Models: General