Yes, I agree with the point you are making. Random play is a relatively good evaluator, but it is not a great evaluator. And it's very weak at tactics. Letting it do a lot of simulations does not cause it converge to the correct value.
But the current breed of MC computer players do not have a fixed tree - they continuously expand the tree in best first manner. Perhaps we use the wrong terminology when we call these MC players because they are hybrids. But I think that's understand now when we say "Monte Carlo player." - Don On Sat, 2006-11-25 at 10:05 +0000, Jacques Basaldúa wrote: > Maybe I did no explain my point well enough. > > The problem with infinite is that we get a better approximation to a > wrong value. > > With few simulations we get that value with, say 1/10 error. With an > astronomical amount > of simulations we get the same value with an error of 1e-200, but it's > still wrong!. It is > proved that simulating a go position converges, but it does not converge > to the same > value as if the position was played by perfect players, it only > converges to the asymptotic > limit of random play. > > I am not an MC developer, but as far as I know, UCT keeps a limited > (i.e. n-ply) tree > in memory and intentionally unbiasses the nodes to make the convergence > faster, that > does not change anything, assuming constant tree size. > > A simple test : > 1: after 100 simulations, choose the highest number in (0.96, 2.1, 3.18) > 2: after 1e9 simulations, choose it in (0.9999999, 2.0000001, 3.000001) > You chose the same value (= same move). > > That's why, I insist, if you don't increase the size of the tree and > only get a better > approximation to a wishful but frequently misconceived value (the limit > of random > play) witch is *not* a good evaluation of the game, you don't > significantly improve > your play. Of course, if you increase the tree, you reach perfect play, > that's not > the point. > > Jacques. > _______________________________________________ > computer-go mailing list > [email protected] > http://www.computer-go.org/mailman/listinfo/computer-go/ _______________________________________________ computer-go mailing list [email protected] http://www.computer-go.org/mailman/listinfo/computer-go/
