Thursday, January 28, 2016

More Computer Go

One reason the triumph of AlphaGo over its human opponent made such big shock waves is that defeating a professional is a big jump over the best previous computer results. Long after computers had beaten the best humans, strong teenage amateurs could still beat computers while giving them long odds. Fan Hui, the European champion, is a 2 dan professional, much stronger than those amateurs, but still far below Lee Sedol, the strongest human Go player. Lee Sedol is a 9 dan professional.

There is no neat equivalence between go strength levels and chess levels, but roughly speaking a 2-dan professional is something like an International Master in Chess. 9-dans are like the so-called super-Grandmasters, whereas Lee Sedol is the Magnus Carlson of go. There is a pretty big gap between a 2-dan pro and a 9-dan, and a significant gap between a "generic" 9-dan and Lee Sedol. Consequently we can't assume that Lee Sedol is going go down just because Fan Hui did.

Sedol also has at least 5 of AlphaGo's games to study (maybe more) but you may be sure that AlphaGo has assiduously studied every one of Lee Sedol's hundreds or thousands of games. Alex Tabarrok has a short note on the computer victory here. Nature collects reactions of the go community here.


Win or lose, I will bet that Lee Sedol is the last human champion the world will ever know. - See more at:

We will still have human champions of course (we still have human chess champions), it's just unlikely that they will be able to beat the strongest computers.

It took a couple of decades for technology to put the computing power to beat a chess grandmaster on your laptop. I'm going to guess that the it won't take that long to put that go champ on a laptop - the voice and face recognition software looks a lot like the kind of computer that beat Fan Hui.