1. Department of Economics, Chongqing Technology and Business University, Chongqing, PR China;
2. Department of Actuarial Studies & Business Analytics, Macquarie University, Macquarie Park, Australia;
3. School of Mathematics and Statistics, Chongqing Technology and Business University, Chongqing, PR China;
4. School of Public Administration, Sichuan University, Chengdu, PR China