1. School of Economics, Tianjin University of Commerce, Tianjin, China
2. Newcastle Business School, Northumbria University, Newcastle Upon Tyne, UK
3. School of Information and Computer Science, Northumbria University, Newcastle Upon Tyne, UK
4. Department of Mathematics and Statistics, Hazara University Mansehra, Dhodial, Pakistan
5. School of Statistics, Jiangxi University of Finance and Economics, Nanchang, China