[jkkramer]

I would call its style unorthodox rather than nonhuman. It still plays common josekis (standard opening sequences) but often chooses uncommon variations. Its mid game is full of startling moves backed by VERY good reading. There's definitely still discernible strategy that us mortals can learn from.

If I recall correctly, the version that beat Lee Sedol was trained on amateur games plus self-play. My guess would be that this new version relies more heavily on pro games.

[drcode]

> My guess would be that this new version relies more heavily on pro games.

Unlikely, since AlphaGo can now generate large numbers of "pro quality" games from scratch. I think it's far more likely it is an autodidact at this point.

[EGreg]

They solved heads up poker in this manner recently. They claim that the chances anyone can beat this computer in the long run are now infinitesimal.

http://poker.srv.ualberta.ca/about

[rictic]

The version that beat Lee Sedol was trained on pro games.

[dfan]

Their Nature paper says "We trained the policy network p_sigma to classify positions according to expert moves played in the KGS data set. This data set contains 29.4 million positions from 160,000 games played by KGS 6 to 9 dan human players; 35.4% of the games are handicap games."

It is possible that they fed it some pro games after the Fan Hui games but before the Lee Sedol games, but that would be weird; at that point it was already learning from self-play rather than trying to match human moves.

That said, I don't think that Master's better performance comes from being trained on pro games. The AlphaGo version that played Lee Sedol played much more like a human pro than Master does.

[jkkramer]

Got a source? I can only find references to training on amateur games (e.g. https://en.wikipedia.org/wiki/AlphaGo_versus_Lee_Sedol#Alpha...)

[conistonwater]

> Its mid game is full of startling moves backed by VERY good reading.

This is pretty similar to what chess engines do.

[Retric]

Perfect play is likely inhumanly aggressive on blacks part part and white making zero moves. Compared to that this is very human style of gameplay simply based on a different strategy culture as it where.

[tasuki]

I don't see why perfect black play should be any more aggressive than perfect white play. Care to elaborate?