Southwest Jiaotong University, Southwest Jiaotong University, Southwest Jiaotong University, Lanzhou Jiaotong University, Southwest Jiaotong University, Southwest Jiaotong University, Southwest Jiaotong University, affiliation not provided to SSRN, affiliation not provided to SSRN, Southwest Jiaotong University, Southwest Jiaotong University and Southwest Jiaotong University