1. School of Statistics and Mathematics, Interdisciplinary Research Institute of Data Science, Shanghai Lixin University of Accounting and Finance, Shanghai, People's Republic of China
2. Department of Mathematics and Statistics, McMaster University, Hamilton, Ontario, Canada
3. Department of Mathematical Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, People's Republic of China
4. School of Finance, Shanghai Lixin University of Accounting and Finance, Shanghai, People's Republic of China