Re: computer-go: minimax and go

[Dave Dyer <ddyer@xxxxxxxxxxx>]

The basic arithmetic is this:  

To do a 10 ply brute force search in Chess might in principle have to examine 
25^10 ~= 9.5e13 nodes

To do a 10 ply brute force search in Go might in principle have to examine
200^10 ~= 1.024e23 nodes

that's a billion times harder.


Now factor in that chess programs get very good reductions in the
raw numbers because very strong, fast, simple evaluators prune out
most of the really bad nodes without having to evaluate them.

Now factor in that in go, even very simple, local problems require reading
15 - 20 ply, and there are usually many such "simple" problems on the
board at once, so reading the full outcome of a midgame position 
could easily require 100 ply.

Now factor in that in go, there are no "strong, simple, fast" evaluators.