The RePEC (Research Papers in Economics) rankings are probably the most widely respected ranking of academic economists worldwide. You can see the New Zealand ranking (based on the last ten years) here. The University of Waikato is well represented - as I am writing, we have three of the top ten, and six of the top twenty, economists in the country. You have a scroll a little way down to find me (at #38).
The ranking is based purely on research publications and their quantity and quality, but only considers publications in economics journals (which in part explains why I'm not ranked higher - so many of my publications are in public health and interdisciplinary journals). Anyway, I'm sure there are ways to game the rankings, if one digs into the algorithm. And given that most economists watch these rankings, there is no doubt benefits to gaming the system if you know how to do so.
According to this 2018 article published in the journal Applied Economics Letters (ungated earlier version here), by Justus Meyer and Klaus Wohlrabe (both University of Munich), it is possible to free ride to some extent in the RePEc rankings. As they explain:
The ongoing procedure of measuring an author’s overall ranking is to adjust backwards for the publishing journal’s quality. RePEc currently adjusts by weighing an author’s publication by the publishing journal’s current impact factor (IF). Impact factors, however, change over time... The reweighting of old articles by current impact factors raises the chance of involuntary free-riding. Authors benefit through previous publications in journals that climb the quality ladder over time.
Does the re-weighting of journal quality make much difference? It turns out that yes, it does. Meyer and Wohlrabe re-rank all 45,000 authors in RePEc, re-weighting the quality of their journal publications by the impact factor during the year in which the article was published. They find that:
...the average change for the top 100 is −12 places and for the top 1000 is −40 place. Among the top 1000 authors ordered by the initial RePEc ranking, the biggest gain is an improvement of 510 places while another author drops by 1600 places.
Drilling down to the top 20 economists (by the ranking at the time of this research), the big gainers are Robert Barro (up 9 places to 11th) and Timothy Besley (up 8 places to 9th), while the big losers are John Siegfried (down 23 places to 34th) and John List (down 17 places to 26th).
Have Meyer and Wohlrabe identified a real problem though? It seems unlikely. Notice that this 'free riding' that they document involves economists anticipating which top journals will rise in impact factor in the future, and publishing in those journals. It seems unlikely that anyone has the perfect foresight necessary to free ride purposefully. So, I wouldn't read too much into the changes as a result of their re-weighting. It's probably not accurate to label future Nobel Prize winner John List a free rider just yet.
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