Computer Go - Performance

Performance

Go has long been considered a difficult challenge in the field of AI and is considerably more difficult to solve than chess. Mathematician I. J. Good wrote in a 1965 New Scientist

"Go on a computer? – In order to programme a computer to play a reasonable game of Go, rather than merely a legal game – it is necessary to formalise the principles of good strategy, or to design a learning programme. The principles are more qualitative and mysterious than in chess, and depend more on judgment. So I think it will be even more difficult to programme a computer to play a reasonable game of Go than of chess."

The first Go program was written by Albert Zobrist in 1968 as part of his thesis on pattern recognition. It introduced an influence function to estimate territory and Zobrist hashing to detect ko.

Recent developments in Monte Carlo Tree Search and machine learning have brought the best programs to high dan level on the small 9x9 board. In 2009, the first such programs appeared which could reach and hold low dan-level ranks on the KGS Go Server also on the 19x19 board.

In 2012, the best Go program on KGS is ranked 6 dan. In 1998, very strong players were able to beat computer programs at handicaps of 25–30 stones, an enormous handicap that few human players would ever take. There was a case in the 1994 World Computer Go Championship where the winning program, Go Intellect, lost all 3 games against the youth players on a 15-stone handicap. In general, players who understood and exploited a program's weaknesses could win with much larger handicaps than typical players.