1. School of Finance, Nankai University, Tianjin 300350, China
2. School of Economics and Management, Shanxi Normal University, Taiyuan 030031, China
3. Postdoctoral Station of Applied Economics, Fudan University, Shanghai 200433, China
4. Postdoctoral Research Station of Guangxi Beibu Gulf Bank, Nanning 530000, China
5. School of Economics and Management, Southwest University, Chongqing 400715, China