1. Pacific Agri-Food Research Centre, Agriculture and Agri-Food Canada, 4200 Highway #97, Summerland, BC VOH1Z0, Canada.
2. Department of Economics and Management, China Agricultural University, 17 Qinghua Dong Lu, Haidian, Beijing, People’s Republic of China.
3. Department of Agricultural and Applied Economics, University of Georgia, 1109 Experiment Street, 212 Stuckey Building, Griffin, GA 30223-1797, USA.
4. Department of Geography, University of Winnipeg, Winnipeg, MB R3B 2E9, Canada.