Nanjing University of Information Science and Technology, Leibniz Institute of Agricultural Development in Transition Economies (IAMO), Beijing Normal University, Nanjing University of Information Science and Technology, Nanjing University of Information Science and Technology, affiliation not provided to SSRN, Nanjing University of Information Science and Technology, Nanjing University of Information Science and Technology, affiliation not provided to SSRN and Nanjing University of Information Science and Technology