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Statistics from Altmetric.com
There is plenty written about metrics, both comparing one type with another and also trying to decide whether they are any use or not. The function of this article is not to endorse any particular metric, but instead to give you some basics so that you can understand conversations about them.
What is the metric for?
If you publish a piece, your wish is for that piece to change practice or alter the world’s understanding of your area in some way. The metric intends, therefore, to tell you something about how far your message may spread. The bodies who fund research will be keen that their research is read and has an impact, which brings us to the first of the three major metrics we will discuss here.
Impact factor
This is a journal-level metric, meaning that it assesses the whole journal, and not a specific article. It is described in a number of papers1 but, in short, it is a ratio of the number of citations of articles to the number of articles over a time period—2 years for the standard impact factor (IF). So, imagine a journal through 2013 …
Footnotes
Competing interests None declared.
Provenance and peer review Commissioned; externally peer reviewed.