1. Research Center for Contemporary Management, Key Research Institute of Humanities and Social Sciences at Universities, School of Economics and Management, Tsinghua University, Beijing 100084, China;
2. School of Business, Renmin University of China, Beijing 100872, China;
3. College of Engineering, University of California, Berkeley, California 94704;
4. Faculty of Engineering, The University of Hong Kong, Hong Kong 999077, China;
5. Faculty of Business and Economics, The University of Hong Kong, Hong Kong 999077, China;
6. International Institute of Finance, School of Management, University of Science and Technology of China, Hefei, Anhui 230026, China