First Author:   Hsiao-chi Chen Department of Economics, National Taipei University hchen@mail.ntpu.edu.tw   151, University Road, San-Shia District New Taipei City, 23741, Taiwan, ROC.   886-2-86741111-ext.67128(Phone) 886-2-86741111-ext.67128(Fax) Second Author: Shi-miin Liu Department of Economics, National Taipei University shimiin@mail.ntpu.edu.tw   New Taipei City, 23741, Taiwan, ROC.