3 ms·
Right idea, wrong execution. If 64^N = 361^M then N log 64 = M log 361, so M = (log 64 / log 361) N ~= 0.71N. So if you could look 12 moves ahead in chess, this
by gjm11 17y ago
Right idea, wrong execution. If 64^N = 361^M then N log 64 = M log 361, so M = (log 64 / log 361) N ~= 0.71N. So if you could look 12 moves ahead in chess, this estimate would say you could manage 8 or 9 moves in go.
Unfortunately, it's worse than this. In practice, the effective branching factor in a chess tree-search is more like 3 than 64, roughly because lots of moves can quickly be found to be bad. I would be very surprised if the corresponding figure for go were less than, say, 30. So now your factor is log 3 / log 30, or more like 1/3.
On top of that, go games are much longer than chess games, so your search depth in go is a much smaller fraction of the whole game, so the search is a worse proxy for the final result. Slightly related to that: there's no nice simple measurement of how well you're doing that's comparable to measuring material in chess. (Your ultimate goal is to build territory, but it takes quite a while before any sort of quantitative estimate of how much territory each player has is feasible, especially if you want it to be anywhere near as cheap as a material count in chess.)