Published on in Vol 7 , No 1 (2019) :January
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/12297, first published
.

1 eHealth Research Institute, School of Management, Harbin Institute of Technology, Harbin, China
2 Department of Statistics, University of California at Riverside, Riverside, CA, United States