Thomson Reuters has completely reformatted the Journal Citation Reports (JCRs) at their website, but eventually I was able to sift through the new layout and find most of what I wanted. One of the documents, the Journal Profile Grid, is an Excel sheet in 5-point font. While this is easily correctable, it is annoying on first reading.
As I mentioned in a post last month, 2015 had flat-to-slightly-down 2-year and 5-year Impact Factors. However, in the long term, JGR‘s Impact Factor has been trending slightly upward. It was never above 3.0 in 2007 and earlier, yet has never been below 3.0 from 2008 onward. Here is a nice little graphic from the JCR showing that trajectory:
So, it’s done this (a brief, small dip) before. The little hiccup as of late might be just that, a blip in the long-term upward trend. Or it could be the start of something bad. Let’s hope for the former, not the latter.
Following what I did last year with JCR details, here are some other tidbits of information about JGR.
- Total cites: rose by ~5% to an amazing 198,000. This is a huge number for a discipline-specific journal. Here’s a chart of JGR total cites by year:
- Self cites: down a little at 18%. I don’t actually know what this means. A high number (above 10%, say) could be a sign of dominance in the field or it could be a sign of isolation and disconnection from the field. We’ll go with the former.
- Immediacy index: dropped just a bit to 0.61. Remember, this is cites in 2015 to JGR papers published in 2015; most of the papers in the second half of the year have zero citations.
- Cited half-life: still greater than 10 years. So, on average, more than half of the citations to a JGR paper occur 10+ years after its publication.
- Citing half-life: ever-so-slightly up to 9.4 years. This is the “age” of references in JGR
- References per paper: up by one to 56. They count papers with more than 100 references as “review articles” rather than “regular” research papers.
- Eigenfactor score: dropped ever-so-slightly to 0.31. This value is based on the 5-year Impact Factor but removes self-cites and then weights citations based on the strength of the citing journal. This is a decent value.
- Article Influence Score: down a bit to 1.39. This is a discipline-normalized version of the Eigenfactor. Values above unity are good.
All of these metrics are explained in more detail in an earlier post. And again, remember, this is for all of JGR, not just JGR Space Physics.