1. Institute of Rural Development; China Academy of Social Sciences; Jian-Guo-Men-Nei Str. 5 100732 Beijing China
2. School of Agricultural Economics and Rural Development; Renmin University of China; 100872, Beijing China
3. Department of Agricultural Economics and Rural Development; University of Göttingen; MZG 10.121, Platz der Göttinger Sieben 5 37073 Göttingen Germany
4. Division of Economics, School of Humanities and Social Sciences; Nanyang Technological University; 14 Nanyang Drive 637332 Singapore