Table 2.
Descriptions of all variables.
| Variable | Description |
| RT7D | # of retweets in the first 168 hours |
| preprint | =1 if the tweet source is a preprint article |
| peer | =1 if the tweet source is a peer-reviewed article |
| letter | =1 if the tweet source is a journal opinion/letter piece |
| scientist | =1 if the user is classified as a doctor or researcher in the life science and biomedical fields |
| liwc_positive | # of positive emotion dictionary words identified by LIWCa 2015 |
| liwc_negative | # of negative emotion dictionary words identified by LIWC 2015 |
| emotion: joy | =1 if the tweet text is predicted to have a salient emotion of joy |
| emotion: anger | =1 if the tweet text is predicted to have a salient emotion of anger |
| emotion: fear | =1 if the tweet text is predicted to have a salient emotion of fear |
| emotion: sadness | =1 if the tweet text is predicted to have a salient emotion of sadness |
| emotion: neutral | =1 if the tweet text is predicted to have no specific emotion |
| log_follower | (log) number of followers the user had |
| verified | =1 if the user is a verified user |
| length | # of words in the tweet text |
| hashtags | # of hashtags used in the tweet |
| mention | =1 if the tweet contains any mention of other users |
| title_length | # of words in the reference article in preprints or journal |
| title_liwc_pos | # of positive emotion words in the title identified by LIWC 2015 |
| title_liwc_neg | # of negative emotion words in the title identified by LIWC 2015 |
| log_cov_tweet | (log) rolling 7-day total number of global coronavirus tweets |
| log_cov_case | (log) rolling 7-day total number of global new confirmed COVID cases |
| log_cov_fatality | (log) rolling 7-day total number of global new confirmed COVID fatalities |
aLIWC: Linguistic Inquiry and Word Count.