1. School of Management and Economics, Beijing Institute of Technology, Beijing 100081, People's Republic of China;
2. PBC School of Finance, Tsinghua University, Beijing 100083, People's Republic of China;
3. Faculty of Finance, Cass Business School, City, University of London, London EC1Y 8TZ, United Kingdom;
4. School of Management, University of Bath, Bath BA2 7AY, United Kingdom