BGonline.org Forums

501 Essential Backgammon Problems #45 -- Rollout + Variants

Posted By: Igor
Date: Thursday, 29 August 2013, at 6:44 p.m.

In Response To: 501 Essential Backgammon Problems #45 (Igor)

Robertie recommends 13/10 over 8/5 for all the obvious reasons; this is the play that I also would have chosen. But the rollout is in slight favor of 8/5.

 White is Player 2 score: 0 pip: 155 Unlimited GameJacoby pip: 156 score: 0 Blue is Player 1
XGID=-aa--BD-C---dD---c-d-bA-A-:0:0:1:32:0:0:1:0:10
Blue to play 32

1.Rollout124/22 8/5eq: +0.174
 Player:Opponent: 53.21% (G:16.57% B:0.50%)46.79% (G:10.26% B:0.41%) Conf.: ± 0.003 (+0.171...+0.178) - [100.0%]Duration: 1 hour 41 minutes
2.Rollout124/22 13/10eq: +0.161 (-0.014)
 Player:Opponent: 53.31% (G:15.69% B:0.51%)46.69% (G:10.73% B:0.44%) Conf.: ± 0.004 (+0.157...+0.164) - [0.0%]Duration: 1 hour 46 minutes
1 20736 Games rolled with Variance Reduction.
Dice Seed: 94782038
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10

Can we make 13/10 come out on top? Sure, how about an added incentive to unstack the midpoint? (At the same time it also reduces the number of attackers in the zone for blue.)

 White is Player 2 score: 0 pip: 155 Unlimited GameJacoby pip: 163 score: 0 Blue is Player 1
XGID=-aa--BC-C---dE---c-d-bA-A-:0:0:1:32:0:0:1:0:10
Blue to play 32

1.Rollout124/22 13/10eq: +0.133
 Player:Opponent: 52.99% (G:13.93% B:0.50%)47.01% (G:11.12% B:0.44%) Conf.: ± 0.011 (+0.122...+0.144) - [100.0%]Duration: 16 minutes 07 seconds
2.Rollout124/22 8/5eq: +0.086 (-0.047)
 Player:Opponent: 51.36% (G:14.24% B:0.49%)48.64% (G:10.91% B:0.45%) Conf.: ± 0.010 (+0.076...+0.096) - [0.0%]Duration: 15 minutes 18 seconds
1 2592 Games rolled with Variance Reduction.
Dice Seed: 42093345
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10

At DMP 13/10 is just a hair ahead.

 White is Player 2 score: 0 pip: 155 1 point match pip: 156 score: 0 Blue is Player 1
XGID=-aa--BD-C---dD---c-d-bA-A-:0:0:1:32:0:0:0:1:10
Blue to play 32

1.Rollout124/22 13/10eq: +0.067
 Player:Opponent: 53.37% (G:17.35% B:1.81%)46.63% (G:13.19% B:1.30%) Conf.: ± 0.002 (+0.066...+0.069) - [100.0%]Duration: 39 minutes 29 seconds
2.Rollout124/22 8/5eq: +0.063 (-0.004)
 Player:Opponent: 53.15% (G:17.89% B:1.57%)46.85% (G:12.04% B:1.15%) Conf.: ± 0.001 (+0.062...+0.064) - [0.0%]Duration: 36 minutes 09 seconds
1 15552 Games rolled with Variance Reduction.
Dice Seed: 94782038
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

Finally, GS and GG results:

 White is Player 2 score: 0 pip: 155 2 point match Crawford pip: 156 score: 1 Blue is Player 1
XGID=-aa--BD-C---dD---c-d-bA-A-:0:0:1:32:1:0:1:2:10
Blue to play 32

1.Rollout124/22 8/5eq: -0.143
 Player:Opponent: 52.71% (G:18.19% B:1.66%)47.29% (G:9.84% B:0.87%) Conf.: ± 0.002 (-0.144...-0.141) - [93.4%]Duration: 43 minutes 18 seconds
2.Rollout124/22 13/10eq: -0.144 (-0.002)
 Player:Opponent: 52.48% (G:17.13% B:1.79%)47.52% (G:9.69% B:0.88%) Conf.: ± 0.002 (-0.146...-0.143) - [6.6%]Duration: 45 minutes 01 second
1 20736 Games rolled with Variance Reduction.
Dice Seed: 94782038
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

 White is Player 2 score: 1 pip: 155 2 point match Crawford pip: 156 score: 0 Blue is Player 1
XGID=-aa--BD-C---dD---c-d-bA-A-:0:0:1:32:0:1:1:2:10
Blue to play 32

1.Rollout124/22 8/5eq: +0.408
 Player:Opponent: 53.57% (G:16.85% B:1.09%)46.43% (G:12.35% B:1.30%) Conf.: ± 0.003 (+0.406...+0.411) - [100.0%]Duration: 20 minutes 18 seconds
2.Rollout124/22 13/10eq: +0.402 (-0.007)
 Player:Opponent: 53.61% (G:16.47% B:1.14%)46.39% (G:13.76% B:1.43%) Conf.: ± 0.003 (+0.399...+0.404) - [0.0%]Duration: 21 minutes 25 seconds
1 10368 Games rolled with Variance Reduction.
Dice Seed: 94782038
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

Post Response

Subject:
Message: