[mjn]

That does seem to be the case. I'd be interested in some kind of median-citedness measure as well, to distinguish a venue that publishes 100 high-impact articles a year, from a venue that publishes 10,000 articles a year, of which 100 are high-impact.

In particular, it's not robust to one factor often mentioned in the bibliometrics literature, trivial changes in agglomeration size. Say a set of 200 articles are published by either: 1) a single journal; or 2) two journals, which publish 100 of them each. In each of the hypotheticals, individual articles have the same citation counts. Under this metric, #1 gets a higher ranking, meaning that you can raise rankings without increasing paper quality by just agglomerating journals. (You can even run the two former journals separately inside the new journal if you want, with a two-track review structure, as long as there's only one title on the front page.)