1. School of Economics and Business Administration, Chongqing University,Chongqing,CHINA,400044
2. H. Milton Stewart School of Industrial and Systems Engineering Georgia Institute of Technology,Atlanta,Georgia,USA,30332-0205
3. Guanghua School of Management, Peking University,Beijing,CHINA,100871
4. North Carolina State University,Edward P. Fitts Department of Industrial and Systems Engineering,Raleigh,NC,USA,27695-7906