1. Department of Management Science and Information Systems, Guanghua School of Management, Peking University, Beijing 100871, China;
2. Department of Systems Engineering and Operations Research, George Mason University, Fairfax, Virginia 22030;
3. Institute for Systems Research, Robert H. Smith School of Business, University of Maryland, College Park, Maryland 20742;
4. Department of Management Science, Fudan University, Shanghai 200433, China;
5. Robert H. Smith School of Business, University of Maryland, College Park, Maryland 20742