[cobaltblue]

This is not quite correct either. 1p is of course generally much stronger than an arbitrary amateur dan (even some (many? most?) 9d amateurs) and you can advance up the pro ranks quickly by winning certain games, but you can see the histograms yourself that while there's a clump of 9ps everywhere but China there's still a distribution. http://senseis.xmp.net/?ProfessionalRankHistograms Another problem is you don't lose your 9p rank once you earn it. It would be nice if there was an international Elo system tracking all the 9ps of various countries to rank them properly... Maybe someone's tried to calculate rankings independently? Still, I think it's pretty uncontroversial that someone who's been a lower-rank pro for longer than a few years is going to be significantly weaker than their higher-rank peers.

[hyperpape]

There are two major attempts at international ratings today. Dr. Bae Taeil does ratings for Korea, and Remi Coulom produces ratings independently, based on the database at go4go.net (http://goratings.org is the site).

Taeil's method seems unusual, though it may well be justified . I think he's using a relatively complete database of games, but I don't know for sure. Coulom has a very well regarded mathematical model, but we know that there are some gaps in the database, which a) may skew international comparisons, and b) may result in inaccurate ratings for players with few games in the database (but those players are usually not top players in the world).

See my comment below: there are very few 1p players near the top, unsurprisingly.