1. Department of Economics, Northern Illinois University, DeKalb, IL, USA
2. Department of Economics, University of California, Irvine, Irvine, CA, USA
3. College of Economics and Management, Nanjing Agricultural University, Nanjing, People’s Republic of China
4. Department of Chemistry and Watershed Institute for Collaborative Environmental Studies, University of Wisconsin-Eau Claire, Eau Claire, WI, USA
5. Department of Economics, University of Wisconsin-Eau Claire, Eau Claire, WI, USA