Facebook: Comments, Likes, and Shares
Can apply to: All scholarly products
Metric definition: Comments, likes, and shares are user-generated actions that can be taken on Facebook posts.
Metric calculation: A “comment” is counted when a user remarks upon a post that includes a link to a scholarly product. “Likes” are calculated based on the number of likes and shares for a URL, likes and comments on Facebook stories about the URL, and inbox messages containing the URL as an attachment. A “share” is counted when a Facebook user shares a link to a scholarly product with his or her Facebook friends, possibly adding commentary.
Data sources: Facebook, as collected and parsed by Altmetric and PlumX
Appropriate use cases: Interactions on Facebook can be an indicator of general public interest and engagement, or engagement with a particular community.
Limitations: Altmetric and Impactstory only track a fraction of Facebook activity for research, because they track public shares of scholarly products. Facebook counts should not be used as measures of quality or impact.
Inappropriate use cases: The correlation between Facebook shares, comments, and likes is weak and should not be used as a leading indicator of citations.
Transparency: Altmetric and Impactstory only report Facebook shares on a manually curated set of publicly facing Facebook pages, meaning the shares are fully auditable. PlumX links out to public Facebook activity, where possible, but also reports the number of private shares, comments, and likes, which are not auditable.
Timeframe: Facebook was publicly launched in February 2004. In theory, research of any age can be shared on Facebook.