1. School of Finance and Economics, Xi’an Jiaotong University, Xi’an 710061, China
2. International Business School, Shaanxi Normal University, Xi’an 710119, China
3. College of Economics and Management, Southwest University, Chongqing 400715, China
4. College of Business, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
5. National Center for Mathematics and Interdisciplinary Science, Chinese Academy of Sciences, Beijing 100190, China