Friday, 11 January 2013

It's tough being an academic economist these days

A new working paper on NBER is entitled "Nine facts about top journals in economics", by David Card and Stefano DellaVigna.

It's a descriptive paper presenting the trends around submissions and publications of journal articles in the top five economic journals (as picked by the authors): American Economic Review (AEA), Econometrica (Econometric Society), Journal of Political Economy (Chicago), Quarterly Journal of Economics (Oxford/Harvard), and Review of Economic Studies (Oxford). 

Here are some of the most interesting findings: 
"First, the number of yearly submissions nearly doubled from 1990 to 2012..."

Source: Card, DellaVigna (2013) "Nine facts about top journals in economics"
 NBER Working Paper 18665
"Second, the total number of articles published in the top journals declined from about 400 per year in the late 1970s to around 300 per year in 2010‐12. The combination of rising submissions and falling publications led to a sharp fall in the aggregate acceptance rate, from around 15% in 1980 to 6% today. The increasing difficulty in publishing in the top‐5 journals may have important implications for the setting of hiring and promotion benchmarks in the field." 
The quantity has increased so it's only natural to focus on keeping quality of the papers received on the same level as before. The upsurge of higher education has opened the scientific fields to a variety of new potential entrants. Stiffer competition in the field can only bring about more quality of the published material.

Source: Card, DellaVigna (2013) "Nine facts about top journals in economics"
 NBER Working Paper 18665
"Third, the American Economic Review is the only top‐5 journal that has substantially increased the number of articles it publishes per year, and as a result now accounts for 40% of top journal publications in the field, up from 25% in 1970. Assuming that promotion, hiring, and pay decisions continue to value the top‐5 journals more or less equally, the AER now exerts a substantially larger influence over the field than it used to."
This "monopoly" of the AER isn't good news for the filed. It will be a problem if the AER becomes more focused on quantity rather than quality of its papers. I doubt it however, since the papers published there are still state of the art work.
"Fourth, published papers in the top‐5 journals are nearly 3 times longer today than they were in the 1970s. Though the journals as a group have increased their total pages, they have not fully adjusted, leading to the decline in the number of published papers. "
"Fifth, the number of authors per paper has increased monotonically from 1.3 in 1970 to 2.3 in 2012, partly offsetting the decrease in the number of articles published per year. Indeed, weighting each paper by the number of co‐authors, the number of authors with a top‐5 journal article in a given year is somewhat higher today than in the 1970s or 1980s." 
"Sixth, papers published in the top‐5 economics journals are highly cited: among those published in the late 1990s, for example, the median article has about 200 Google Scholar citations. Citations for more recently published articles are lower, reflecting the fact that it takes time to accumulate citations. Interestingly, papers published in the 1970s and 1980s also have total citation counts below those of papers published in the 1990s, reflecting the nature of the sources used by Google Scholar, citation practices of current authors, and other potential factors."
Source: Card, DellaVigna (2013) "Nine facts about top journals in economics"
 NBER Working Paper 18665
This is a very interesting finding. If I understood it correctly, the 1990s presented the biggest boom in the development of economic sciences. Perhaps this can be related to technological improvements in writing software and/or improvements in generating and measuring data.
"Seventh, citation‐based rankings of the top‐5 journals are fairly stable over time, with the notable exception of the Quarterly Journal of Economics which climbed from second‐to‐last to first place among the top‐5." 
"Eighth, citations are strongly increasing in both the length of a paper and the number of coauthors, suggesting that trends in both dimensions may be driven in part by quality competition. The effects hold both when predicting the number of citations (in logs) and when predicting the probability of an article in the top 5% of citations in a given year." 
"Ninth, despite the relative stability of the distribution of published articles across fields, there are interesting differences in the relative citation rates of newer and older papers in different fields. In particular, papers in Development and International Economics published since 1990 are more highly cited than older (pre‐1990) papers in these fields, whereas recent papers in Econometrics and Theory are less cited than older papers in these fields." 
I account this to the newer and more precise findings in these two fields. 

Since we're on the topic of academic journal articles, some readers might find this paper particularly interesting:
"The Nonsense Math Effect"

"Mathematics is a fundamental tool of research. Although potentially applicable in every discipline, the amount of training in mathematics that students typically receive varies greatly between different disciplines. In those disciplines where most researchers do not master mathematics, the use of mathematics may be held in too much awe. To demonstrate this I conducted an online experiment with 200 participants, all of which had experience of reading research reports and a postgraduate degree (in any subject). Participants were presented with the abstracts from two published papers (one in evolutionary anthropology and one in sociology). Based on these abstracts, participants were asked to judge the quality of the research. Either one or the other of the two abstracts was manipulated through the inclusion of an extra sentence taken from a completely unrelated paper and presenting an equation that made no sense in the context. The abstract that included the meaningless mathematics tended to be judged of higher quality. However, this “nonsense math effect” was not found among participants with degrees in mathematics, science, technology or medicine."

1 comment:

  1. So, the size of academic papers has increased along with monetary inflation? An odd correlation.