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Post a position, need a rollout?

Posted By: Timothy Chow
Date: Thursday, 11 April 2024, at 12:13 p.m.

In Response To: Post a position, need a rollout? (rambiz)

I think the only way to do this with XG is to do a separate rollout of every possible opening roll ATS, and average the results. That's a lot of work, but I'm sure Stick already has rollouts of all (or almost all? not sure if he has rollouts of "obvious" opening rolls such as 31) the gammon save/gammon go opening rolls in his files, so it would just be a matter of posting 15+15=30 rollout results. In fact, he used to have these rollouts posted on the BGO home page, but those rollouts are probably out of date anyway.

There's also the little matter of the distinction between pseudocubeless wins/gammons and actual wins/gammons, but these should be the same (or very close, at least) since the cube is dead.

Actually, you can save Stick some work by going through all 30 positions yourself and checking XG's opening book. For example, consider the opening roll of 64:

		White is Player 2 score: 1 pip: 167 2 point match Crawford pip: 167 score: 0 Blue is Player 1
XGID=-b----E-C---eE---c-e----B-:0:0:1:46:0:1:1:2:10
Blue to play 46

1.	Book1	8/2 6/2	eq: +0.306
	Player: Opponent: 50.46% (G:14.82% B:2.17%) 49.54% (G:15.37% B:1.96%) Conf.: ± 0.001 (+0.304...+0.307) - [100.0%]
2.	Book1	24/18 13/9	eq: +0.284 (-0.022)
	Player: Opponent: 51.26% (G:12.92% B:1.49%) 48.74% (G:15.53% B:1.76%) Conf.: ± 0.001 (+0.282...+0.285) - [0.0%]
3.	Book2	13/9 13/7	eq: +0.266 (-0.039)
	Player: Opponent: 48.76% (G:14.56% B:1.78%) 51.24% (G:18.35% B:3.29%) Conf.: ± 0.002 (+0.264...+0.268) - [0.0%]
4.	Book2	24/14	eq: +0.259 (-0.047)
	Player: Opponent: 50.82% (G:12.13% B:1.06%) 49.18% (G:14.95% B:1.62%) Conf.: ± 0.002 (+0.257...+0.261) - [0.0%]
5.	Book3	24/20 13/7	eq: +0.227 (-0.079)
	Player: Opponent: 48.57% (G:12.76% B:0.51%) 51.43% (G:13.32% B:0.61%)
6.	Book3	24/20 24/18	eq: +0.188 (-0.117)
	Player: Opponent: 48.81% (G:10.61% B:0.41%) 51.19% (G:13.42% B:0.51%)
1 Generated by Steven Carey on 7/31/2012 using eXtreme Gammon 2.10 23328 Games rolled with Variance Reduction. Dice Seed: 81668140 Moves and cube decisions: 4-ply 2 Generated by Steven Carey on 7/31/2012 using eXtreme Gammon 2.00 23328 Games rolled with Variance Reduction. Dice Seed: 92170022 Moves: 3-ply, cube decisions: XG Roller 3 Generated by GameSite 2000, Ltd on 5/21/2011 using eXtreme Gammon 2.00 Analyzed in XG Roller++

eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

You can see that the XG opening book already contains a 4-ply/4-ply rollout of 8/2 6/2, which is presumably good enough for your purposes. It's only if the rollout settings are too weak that you'd need to ask Stick for a rollout. For example, XG's opening book has only a 2-ply/3-ply red rollout of an opening 31, so you could ask Stick for a 4-ply/4-ply rollout.

		White is Player 2 score: 1 pip: 167 2 point match Crawford pip: 167 score: 0 Blue is Player 1
XGID=-b----E-C---eE---c-e----B-:0:0:1:31:0:1:1:2:10
Blue to play 31

1.	Book1	8/5 6/5	eq: +0.462
	Player: Opponent: 54.96% (G:18.13% B:1.89%) 45.04% (G:20.25% B:1.97%) Conf.: ± 0.004 (+0.458...+0.465) - [100.0%]
2.	Book1	13/10 6/5	eq: +0.290 (-0.172)
	Player: Opponent: 49.79% (G:14.72% B:1.48%) 50.21% (G:25.35% B:3.55%) Conf.: ± 0.004 (+0.286...+0.294) - [0.0%]
3.	Book1	24/23 13/10	eq: +0.280 (-0.181)
	Player: Opponent: 49.88% (G:14.13% B:1.25%) 50.12% (G:22.89% B:2.13%) Conf.: ± 0.003 (+0.277...+0.284) - [0.0%]
4.	Book2	13/9	eq: +0.254 (-0.208)
	Player: Opponent: 48.86% (G:13.84% B:0.55%) 51.14% (G:13.44% B:0.71%)
5.	Book2	24/20	eq: +0.224 (-0.238)
	Player: Opponent: 49.19% (G:12.01% B:0.42%) 50.81% (G:12.67% B:0.53%)
6.	Book2	24/23 24/21	eq: +0.217 (-0.245)
	Player: Opponent: 48.62% (G:12.20% B:0.43%) 51.38% (G:13.49% B:0.58%)
1 Generated by GameSite 2000, Ltd on 2/26/2011 using eXtreme Gammon 2.00 10368 Games rolled with Variance Reduction. Dice Seed: 38613390 Moves: 2-ply, cube decisions: 3-ply Red 2 Generated by GameSite 2000, Ltd on 5/21/2011 using eXtreme Gammon 2.00 Analyzed in XG Roller++

eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

Messages In This Thread

• Post a position, need a rollout?
  Stick -- Saturday, 16 March 2024, at 2:39 a.m.
  • Post a position, need a rollout?
    rambiz -- Wednesday, 10 April 2024, at 3:09 p.m.
    • Post a position, need a rollout?
      Timothy Chow -- Thursday, 11 April 2024, at 12:13 p.m.
      • Post a position, need a rollout?
        Stick -- Thursday, 11 April 2024, at 7:45 p.m.
        • Post a position, need a rollout?
          Timothy Chow -- Friday, 12 April 2024, at 12:48 a.m.
      • Post a position, need a rollout?
        rambiz -- Friday, 12 April 2024, at 1:08 p.m.
        • Post a position, need a rollout?
          Timothy Chow -- Friday, 12 April 2024, at 1:28 p.m.