1. Guizhou Key Laboratory of Economics System Simulation, Guizhou University of Finance and Economics, Guiyang 550025, P. R. China
2. Guizhou Key Laboratory of Big Data Statistical Analysis, Guiyang 550025, P. R. China
3. School of Mathematical Science, Shanghai Jiao Tong University, Shanghai, P. R. China
4. Department of Mathematics, University of Malakand, KPK, Pakistan
5. University of Massachusetts Medical School (UMASS), Worcester, MA 01655, USA