[computer-go] The dominance of search (Suzie v. GnuGo)

[Chris Fant]

> The results are that in order to keep the same winning rate, you have to
> increase the number of simulations by something a little larger than linear
> in the board area. From 9x9 to 13x13, you need something like 3 times more
> simulations for the same winning rate. Same thing from 13x13 to 19x19. As
> the time of one simulation is linear in the board area, to keep the same
> level you have to give a time which increases as power ~2.5 of the board
> area. So between 9x9 and 19x19, you have to give 32x more time per move for
> the "same play level" (always defined as winning rate against gnugo).
> This is far from being exponential. (maybe if it was exponential, there
> would be little interest to work on 9x9 go).

Here's another way to test this sort of thing that is completely
intrinsic to the engine (doesn't require gnugo):

Start with and empty board and zero komi.  Analyze using UCT until the
winning percentage at the root reaches X.  Note the number of
simulations required (or the amount of time).  Repeat for a larger
board size.  One should probably average N trials at each board size
for more reliable numbers.