Wencheng Zhang, Postdoctoral Researcher, Nankai Institute of International Economics, Nankai University, Tianjin, China. Email: wenchengzhang86@163.com; Shuijun Peng (corresponding author), Professor, Department of International Economics and Business, School of Economics, Xiamen University, Xiamen, China. Email: shuijunAgeng@xmu.edu.cn.