1. Department of Applied Economics and Department of Finance, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan 402, ROC
2. Faculty of Economics, Chiang Mai University, Thailand, and Faculty of Economics, Maejo University, Thailand
3. Econometric Institute, Erasmus School of Economics, Erasmus University Rotterdam, and Tinbergen Institute, The Netherlands, and Institute of Economic Research, Kyoto University, Japan