1. School of Public Administration, Zhejiang University of Finance and Economics, Hangzhou, China
2. Department of Geography, The University of Hong Kong, Hong Kong, China
3. State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, Hubei, China
4. School of Resources and Environment, University of Electronic Science and Technology of China, Chengdu, China
5. Department of Statistics, Iowa State University, Ames, IA, USA
6. Department of Environmental Health Sciences, School of Public Health, University at Albany, Rensselaer, NY, USA