In my last blog post I wrote about impact factors and h-index for different journals. That got me wondering about what the h5 index is for all of the journals that I read and may want to publish in. I could look them all up individually, but that sounds boring and monotonous. I'd much rather figure out how to get R to do it for me. I've never done this kind of thing with R before, so it took a little while, but I wrote a simple function that takes a journal name and returns its h5-index.
Friday, February 8, 2013
Thursday, February 7, 2013
I've been thinking about journal rankings and impact factors lately, partly because I noticed that impact factors and H-index sometimes give quite different rankings for journals. To pick one example, Neuropsychologia and Cortex are two very good cognitive neuroscience journals that publish similar sorts of articles, but the impact factor for Cortex is substantially higher than for Neuropsychologia (6.08 vs. 3.636), whereas the H-index is substantially higher for Neuropsychologia than for Cortex (67 vs. 41). In case you are unfamiliar with these measures, impact factor is basically the mean number of citations to articles that were published in the past 2 years; H-index is the largest number h such that h articles have at least h citations each. So the articles published in Cortex have been cited an average of about 6 times and there are 41 articles that have been cited at least 41 times; the articles in Neuropsychologia have been cited an average of about 3.6 times and there are 67 articles that have been cited at least 67 times. Since both measures are based on citation rates, why do they give different rankings?