1. School of Environment, Tsinghua Univ., Beijing 100084, China.
2. School of Management, Fudan Univ., Nanning 530007, China; School of Finance and Insurance, Guangxi Univ. of Finance and Economics, Nanning 530007, China (corresponding author). ORCID: .
3. Professor, Institute of Western China Economic Research, Southwestern Univ. of Finance and Economics, Chengdu 611130, China.