…0.004 !
There is, these days, no shortage of metrics for quantifying scientists’ impact. Aside from simple counts of citations (i.e. how many times one’s research papers are cited by other papers), there’s the now ubiquitous h-index [1] that combines the number of papers one has published and the citations per paper, as well as a g-index, a-index, C-index, m quotient, and more [2,3]. Even aside from the ridiculous proliferation, I don’t really like these things — they can lead easily to the delusion that knowing a simple number might replace actual labor-intensive evaluation of the merits of one’s work. But finally, there’s an index I can believe in: In a fun-to-read letter in Genome Biology, Neil Hall proposes the Kardashian index, “a measure of discrepancy between a scientist’s social media profile and publication record based on the direct comparison of numbers of citations and Twitter followers. ”
Hall writes:
“Consider Kim Kardashian; she comes from a privileged background and, despite having not achieved anything consequential in science, politics or the arts . . . she is one of the most followed people on Twitter and among the most searched-for person on Google.”
Hall notes that, in this age of social media, we should worry that there are scientists falling into the same mold. For kicks (it’s not a serious paper), he plots number of Twitter followers vs. total number of citations for 40 scientists.
There’s a trend, and he proposes considering deviations from it as a measure of disproportionate social media fame, or lack of fame. (Specifically, K = T / (43.3 * C^0.32), where K is the Kardashian-index, T is the number of Twitter followers, and C is the citation count.) A Kardashian-index much greater than one implies Kardashian-ness; a small Kardashian-index “suggests that a scientist is being undervalued.”
I’ve got two Twitter followers (one of whom I think is a spambot), and 1800 citations, giving me a K-index of 0.004. (If you’re wondering why I even have a Twitter account, see https://eighteenthelephant.wordpress.com/2013/11/19/twitter-cat-pictures-and-other-wonders-of-the-internet-age/.) Having just submitted a paper for publication today, I’m hoping to drive my index still lower…
Update Aug. 18, 2014: The “1800 citations” is from Google Scholar. Web of Science just lists 1100, and has a more accurate list of my publications, so I’ll put more confidence in its count. This pushes my Kardashian Index up, unfortunately, to 0.005!
Update Oct. 4, 2018: I’m now up to 3627 citations (Google Scholar) and 117 Twitter followers, making my Kardashian Index skyrocket to 0.2 ! It will be a sad day if I cross 1…
Update Dec. 10, 2020: There’s an online calculator for one’s Kardashian Index! I’m currently at 0.38, steadily rising but still safely below 1.
— Raghuveer Parthasarathy. August 2, 2014 (& updates)
The Eighteenth Elephant 
The Kardashian index ignores “underground” social media efforts like this. With your vast blog readership you should be considered a Kourtney or perhaps even a Khloe if not a Kim. By the way, I can infer by your children’s names when you must have had a brief infatuation with the Kardashians and followed in their “K” naming scheme.
I like the term “underground” rather than “unpopular” for my blog.