In correspondence at Nature, Barabasi et al. show that the proportion of all citations accruing to the top 1% most-cited papers (a measure of “citation concentration” or “citation inequality”) has been steadily increasing since at least 1990. The top 1% of papers used to accrue about 2-5% of all citations; now they accrue 10-20%. Barabasi et al. only consider papers published in a few leading journals like Nature, Science, and PNAS, but I highly doubt the conclusions would change if you broadened the database–if anything, I bet their conclusions would be strengthened. They note that, as the number of papers increases while the time individuals allocate to reading remains constant, “filtering” the literature becomes an increasing challenge. And as I’ve noted in the past, everybody has strong incentives to filter the literature in the same way. So Barabasi et al. reinforces the point of that old post of mine: not only is what I called “citation concentration” here to stay, it’s getting stronger. New and different search and filtering tools, like Google Scholar, aren’t likely to change that (indeed, Barabasi et al. suggest that new filtering tools are one cause of increasing citation concentration). As long as everyone reads an increasingly small fraction of the literature, and as long as everyone has an incentive to read what everyone else is reading, citation concentration is only going to increase. I’m not saying that’s good, bad, both, or neither (that’s a whole ‘nother conversation)–but that’s the way it is.
Worthwhile Canadian Initiative discusses the arithmetic of tenure standards. Not everybody can be above average–but what if that’s effectively what everybody’s tenure standards require? For instance, the more places that officially or unofficially require pre-tenure faculty to get an NSF grant as a condition for tenure, the more unrealistic that standard becomes, since there are only so many NSF grants to go around.
Recently, I argued that we ecologists should ape our colleagues in other fields of biology and focus more on a relatively small number of model systems. So it’s interesting to see an opinion piece in Nature from a developmental biologist, Jessica Bolker, arguing that biologists have focused on too few model systems. Jessica and I identify pretty much the same advantages and disadvantages of working in model systems vs. non-model systems, though she also makes some good points I neglected. She notes that, insofar as model systems become models just because they happen to have been studied a lot in the past, there’s a haphazardness to our choice of model systems that may not be ideal. That is, there’s a tension between choosing model systems on the basis of “intrinsic” features that make them well-suited to addressing the question asked, and choosing model systems on the basis of the “extrinsic” fact that they’re already well-studied. And she notes that a focus on model systems imparts a certain inertia to our research. If our questions change, and those new questions are essential to address but yet can’t be addressed in current model systems, we’re in trouble if we insist on sticking with current model systems. Interesting to consider the possibility that fields like developmental biology may be erring on the side of too few focal systems, while ecology errs on the side of too many.
Writing in the Guardian, ecological statistician Bob O’Hara reflects on the open access movement, and how and why it has become tied to other movements that at first glance seem unrelated (like the movements to redefine “quality” science, and to measure “quality” using altmetrics). I think Bob’s quite right about how we got to this point, and I share his (deliberately-understated) concerns about how the strongest advocates of open access appear ready to sacrifice other established scientific publishing practices for the sake of the open access cause. But like him, I doubt that the future is one in which open access, author-pays, we-only-care-if-it’s-technically-sound journals like PLoS ONE are the only game in town. The near future likely is one in which author-pays open access journals subsidize “prestige” journals, as at PLoS. One question I have is how many “tiers” of journals will continue to exist. In the not too distant future, will the current multi-tiered system collapse to a two-tiered system? Will every ecologist first take a shot at one of a very small number of highly-selective, prestige journals, and then send papers rejected by those journals straight to an open-access, author-pays journal that evaluates papers only for technical soundness? As someone who publishes in various tiers of journals, and who is old enough to remember when people differentiated journals along multiple axes rather than just a single “prestige” or “impact” axis, I hope not.
Carnival of Evolution #53 is now up at Sorting out Science.
First, a new study finds that women are underrepresented as senior authors in the sciences, including in ecology & evolutionary biology. From 1990-2010, women were 23 percent of authors on publications in ecology and evolutionary biology, but were only 18.5 percent of last authors. The underrepresentation was more extreme in certain subfields, including herpetology.
Second, an article by Marlene Zuk and Sheila O’Rourke asks whether biology is on its way to becoming a “pink-collar” profession. Part of why I liked this article is that it addresses the really common misconception that underrepresentation of women in faculty positions is simply a demographic issue that will resolve itself as the newest crop of PhDs works their way into faculty positions. Studies indicate that women are lost at all the transitions (PhD to postdoc, postdoc to Assistant Professor, etc.), so we cannot count on demography to solve the problem of underrepresentation of women in faculty positions.
From the archives:
Two short and funny old posts:
The best sentences a scientist gets to say. Like “That’s a great question, which my next slide addresses.” Also the best sentences you wish you could say. Like “My work has solved this problem so comprehensively that no further work is needed.” Add your own in the comments!