1. Department of Management, Shijiazhuang Tiedao University, Shijiazhuang 050043, China
2. School of Economics, Shandong University, Jinan 250100, China
3. School of Business, Operations and Strategy, University of Greenwich, Old Royal Naval College, Park Row, London SE10 9LS, UK
4. Business School, Birkbeck, University of London, London WC1E 7HX, UK