1. Quantitative Economics Center, Jilin University, 2699 Qianjin Street, Changchun, Jilin 130012, China PR
2. School of Public Finance and Taxation, Southwestern University of Finance and Economics, 555 Liutai Avenue, Chengdu, Sichuan 611130, China PR
3. School of Economics and Management, Nanchang University, 999 Xuefu Avenue, Nanchang, Jiangxi 330031, China PR