1. School of Statistics and Management, Shanghai University of Finance and Economics, Shanghai 200433, China;
2. Krannert School of Management, Purdue University, West Lafayette, Indiana 47907;
3. Departments of Statistics and Operations Research, Genetics, and Biostatistics, Carolina Center for Genome Sciences, Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599