About the Authors

John F. Helliwell

john.helliwell@ubc.ca

Affiliation Canadian Institute for Advanced Research and Vancouver School of Economics, University of British Columbia, Vancouver, British Columbia, Canada

Haifang Huang

Affiliation Department of Economics, University of Alberta, Edmonton, Alberta, Canada

Competing Interests

One of the data sources for this study is a survey sponsored by Coca-Cola. There are no patents, products in development or marketed products to declare. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: JFH HH. Analyzed the data: JFH HH. Contributed reagents/materials/analysis tools: JFH HH. Wrote the paper: JFH HH.