Right on time for conference season (e.g., CAES in Winnipeg next week, AAEA in New Orleans at the end of the month, and ICAE in Delhi in early August), here are the newly released Journal Citations Report, here is the new top 5 of journals in the “agricultural economics and policy” category:
- Food Policy 6.8
- Agricultural Economics 4.5
- China Agricultural Economic Review 4.4
- Annual Review of Resource Economics 4.2
- American Journal of Agricultural Economics 4.2
The number to the right of each journal name is the journal’s impact factor, which is obtained by dividing the number of citations to a journal’s articles in year t by the sum of the total number of articles published by that journal in years t-1 and t-2.
There certainly are some surprises in this ranking. First, the Canadian Journal of Agricultural Economics, which had an astronomically high impact factors that placed it in the top five these past few years, is now ranked 13th. That’s because the COVID special issue of that journal, which had attracted a lot of citations, is no longer counter in that journal’s impact factor. Like a colleague wrote me in an email: “CJAE … had its moment in the sun…”
Second, I am a bit surprised to find Agricultural Economics and the China Agricultural Economic Review in the top five, not because they are not good journals, but because a lot of the manuscripts we rejected at both of the journals I have edited (i.e., Food Policy and the American Journal of Agricultural Economics) ended up in those journals. Then again, it is useful to remember that impact factors measure how often the articles in a journal get cited, which is at best only correlated (and maybe even only weakly correlated) with the quality of scholarship in that journal. For instance, looking at the RePEc simple impact factor1 ranking (which is closer to how a journal is perceived in the economics profession than simple impact factors) for the five journals above, we have the following rank ordering:
- American Journal of Agricultural Economics 822
- Annual Review of Resource Economics 104
- Agricultural Economics 147
- Food Policy 233
- China Agricultural Economic Review 605
No such measure of “impact” is perfect, and I suspect that if we were to have accurate preference-based measures (i.e., looking at where people would ideally want their work to be published), we would have a very different ranking. The AJAE, for instance, is widely seen as the numéraire in agricultural economics departments (i.e., it is the journal the lens of which tenure and promotion dossiers are seen through), and I suspect most scholars based in places where deans don’t simply add up the number of publications times each publication’s impact factor would rather publish in the AJAE than in, say, some of the other journals in that list. Similarly, in places where policy impact matters,3 Food Policy is seen as the best outlet for one’s work
More broadly, simple impact factors are subject to gaming. At the extensive margin, if citations are the name of the game, then it might be tempting to publish stuff that is obviously going to be controversial, since impact factors cannot differentiate between “good” (i.e., complimentary) and “bad” (i.e., critical) citations. Or it might be tempting to publish literature reviews, which are usually broadly cited. (This is why the ARRE, which only publishes review articles, is cited so well.) At the intensive margin, it might also be tempting to coerce the authors of articles published in a given journal to cite more of the articles in that journal.
All of this means that impact factors are not a very good measure of anything except how often a journal’s articles get cited. When I edited the AJAE, I took seriously the idea that AJAE publications are used as a means of credentialing scholars in our field, and so I opposed the idea of doing special issues or publishing review articles which, while they would have helped with our impact factor, would have diluted the perceived quality of the scholarship published in the journal. (Much like I suspect the editors of the American Economic Review, the Journal of Political Economy, and the Review of Economic Studies are also not losing sleep about not being in the top five journals of RePEc’s simple impact factor ranking…)
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1. From RePEc: “This list provides a simple impact factor, computing a ratio of the number of citations by the number of items in the series. Citation counts are adjusted to exclude citations from the same series. These computations are experimental and based on the citation analysis provided by the CitEc project, which uses data from items listed in RePEc. Only series or journals with 50 or more items are ranked.”
2. The AJAE shows up twice in the RePEc ranking: Once for the journal itself, and once for the appendices to the journal’s articles. I used the highest of those two measures as being representative of the journal’s performance.
3. I am not sure this means policy schools, because who knows what those guys actually value.