Published on in Vol 8, No 7 (2020): July
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/17832, first published
.
1 School of Data and Computer Science, Sun Yat-sen University, Guangzhou, China
2 School of Computer Science, South China Normal University, Guangzhou, China
3 School of Business, Guangdong University of Foreign Studies, Guangzhou, China