1. School of Mathematics and Statistics, Nanjing University of Information Science & Technology, Nanjing, People's Republic of China
2. School of Statistics, Renmin University of China, Beijing, People's Republic of China
3. Department of Statistics, School of Economics, Xiamen University, Xiamen, People's Republic of China
4. Key Laboratory of Econometrics, Ministry of Education, Xiamen University, Xiamen, People's Republic of China
5. The Wang Yanan Institute for Studies in Economics, Xiamen University, Xiamen, People's Republic of China