I agree, this is a position where 2ply is expected to do much better, even cubeless, since it understands the variation tree much better.
It sounds like a good idea though, to make a collection of moves/evals/cubes where 0ply is way of compared to 2ply or rollouts. Christian. On Wed, Jun 25, 2008 at 12:00 AM, Robert-Jan Veldhuizen <[EMAIL PROTECTED]> wrote: > > > On Tue, Jun 24, 2008 at 11:32 AM, Achim Mueller <[EMAIL PROTECTED]> wrote: > >> The point is not a technical bug but the fact that gnubg totally >> misevaluates a position at 0ply that actually should be handled easily. >> I put some more positions at http://www.acepoint.de/index.php?id=37. This >> section will be extended from time to time. >> Another idea is to open a section at www.gnubg.org that can be filled by >> readers and users also. >> > > Actually this one is not so easy I think. A quick 0/2-ply rollout suggests > that this is a heavily cube-influenced checker play: > > 1. Rollout 21/15 8/4 Eq.: +0,431 > 61,3% 7,5% 0,4% - 38,7% 3,4% 0,1% CL +0,283 CF +0,431 > [ 0,1% 0,1% 0,1% - 0,1% 0,1% 0,0% CL 0,003 CF 0,007] > Full cubeful rollout with var.redn. > 1296 games, Mersenne Twister dice gen. with seed 826408977 and > quasi-random dice > Play: 0-ply cubeful prune [expert] > Cube: 2-ply cubeful prune [world class] > 2. Rollout 21/11 Eq.: +0,393 ( -0,037) > 60,6% 5,7% 0,4% - 39,4% 4,8% 0,1% CL +0,230 CF +0,393 > [ 0,1% 0,1% 0,1% - 0,1% 0,1% 0,0% CL 0,003 CF 0,008] > Full cubeful rollout with var.redn. > 1296 games, Mersenne Twister dice gen. with seed 826408977 and > quasi-random dice > Play: 0-ply cubeful prune [expert] > Cube: 2-ply cubeful prune [world class] > 3. Rollout 21/17*/11 Eq.: +0,365 ( -0,066) > 64,1% 11,7% 0,4% - 35,9% 12,2% 0,2% CL +0,293 CF +0,365 > [ 0,1% 0,1% 0,0% - 0,1% 0,1% 0,0% CL 0,003 CF 0,007] > Full cubeful rollout with var.redn. > 1296 games, Mersenne Twister dice gen. with seed 826408977 and > quasi-random dice > Play: 0-ply cubeful prune [expert] > Cube: 2-ply cubeful prune [world class] > > As you can see, the #3 play, gnubg 0-ply's favourite, still has the highest > cubeless equity. It's not surprising that without a lookahead, gnubg fails > to see the future cube implications here. > > I guess what's going on, is that a hit leads to overkill after a dance and > subsequent cube. So, cubeful, you don't reap full benefits of this play when > it works. The alternative play 21/15 8/4 is less volatile and supposedly > leads to more efficient cube usage (after a miss). > > Greetings, > -- > Robert-Jan Veldhuizen _______________________________________________ Bug-gnubg mailing list [email protected] http://lists.gnu.org/mailman/listinfo/bug-gnubg
