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Rollout and Comments

Posted By: Bob Koca
Date: Tuesday, 28 April 2026, at 6:22 p.m.

In Response To: Severe crunch possibility but opponent has 4 on bar (Bob Koca)

Rollout suggests it is a blunder to not double and super easy take.

		White is Player 2 score: 2 pip: 182 7 point match pip: 70 score: 1 Blue is Player 1
XGID=dDCaBCB----------bbbbb---A:0:0:1:00:1:2:0:7:10
Blue on roll, cube action?

Analyzed in Rollout	No double	Double/Take
Player Winning Chances:	50.59% (G:43.77% B:4.04%)	50.22% (G:43.49% B:4.67%)
Opponent Winning Chances:	49.41% (G:10.90% B:0.42%)	49.78% (G:10.33% B:0.51%)
Cubeless Equities	+0.416	+0.989
Cubeful Equities
No double:	+0.388 (-0.129)	±0.019 (+0.369..+0.407)
Double/Take:	+0.517	±0.025 (+0.492..+0.542)
Double/Pass:	+1.000 (+0.483)
Best Cube action: Double / Take
Rollout details
1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller
Double Decision confidence:		100.0%
Take Decision confidence:		100.0%
Duration: 3 minutes 16 seconds

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

The score is important. If changed to 5a 5a instead it is not a double but is close. If changed to Jacobyless money game it is a borderline decision.

		White is Player 2 score: 2 pip: 182 7 point match pip: 70 score: 2 Blue is Player 1
XGID=dDCaBCB----------bbbbb---A:0:0:1:00:2:2:0:7:10
Blue on roll, cube action?

Analyzed in Rollout	No double	Double/Take
Player Winning Chances:	50.68% (G:43.89% B:4.31%)	49.98% (G:43.70% B:5.88%)
Opponent Winning Chances:	49.32% (G:11.02% B:0.40%)	50.02% (G:10.51% B:0.61%)
Cubeless Equities	+0.362	+0.939
Cubeful Equities
No double:	+0.307	±0.021 (+0.286..+0.327)
Double/Take:	+0.276 (-0.031)	±0.028 (+0.247..+0.304)
Double/Pass:	+1.000 (+0.693)
Best Cube action: No double / Take
Percentage of wrong pass needed to make the double decision right: 4.1%
Rollout details
1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller
Double Decision confidence:		96.0%
Take Decision confidence:		100.0%
Duration: 3 minutes 01 second

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

		White is Player 2 score: 0 pip: 182 Unlimited Game pip: 70 score: 0 Blue is Player 1
XGID=dDCaBCB----------bbbbb---A:0:0:1:00:0:0:0:0:10
Blue on roll, cube action?

Analyzed in Rollout	No double	Double/Take
Player Winning Chances:	50.75% (G:43.85% B:3.57%)	50.70% (G:43.68% B:3.42%)
Opponent Winning Chances:	49.25% (G:11.13% B:0.40%)	49.30% (G:11.19% B:0.41%)
Cubeless Equities	+0.374	+0.738
Cubeful Equities
No double:	+0.302 (-0.008)	±0.020 (+0.282..+0.322)
Double/Take:	+0.310	±0.025 (+0.285..+0.335)
Double/Pass:	+1.000 (+0.690)
Best Cube action: Double / Take
Rollout details
1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller
Double Decision confidence:		68.4%
Take Decision confidence:		100.0%
Duration: 3 minutes 12 seconds

eXtreme Gammon Version: 2.10

From the original position and score market losers include 36 as an extremely Huge market loser.

Huge market losers are 21, or any 3 which does not result in getting hit back or opponent rolling 33 to get checkers off the bar. Some of these will have become too good to double.

		White is Player 2 score: 2 pip: 182 7 point match pip: 67 score: 1 Blue is Player 1
XGID=dDCaBCB----------bbbbbA---:0:0:1:00:1:2:0:7:10
Blue on roll, cube action?

Analyzed in Rollout	No double	Double/Take
Player Winning Chances:	66.44% (G:60.70% B:6.72%)	65.79% (G:60.09% B:7.44%)
Opponent Winning Chances:	33.56% (G:5.33% B:0.19%)	34.21% (G:5.42% B:0.20%)
Cubeless Equities	+0.999	+2.230
Cubeful Equities
No double:	+1.052	±0.012 (+1.040..+1.064)
Double/Take:	+1.901 (+0.849)	±0.022 (+1.880..+1.923)
Double/Pass:	+1.000 (-0.052)
Best Cube action: Too good to double / Pass
Percentage of wrong take needed to make the double decision right: 5.8%
Rollout details
1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller
Double Decision confidence:		100.0%
Take Decision confidence:		100.0%
Duration: 2 minutes 20 seconds

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

Messages In This Thread

• Severe crunch possibility but opponent has 4 on bar
  Bob Koca -- Sunday, 26 April 2026, at 3:45 p.m.
  • Severe crunch possibility but opponent has 4 on bar
    Francesco -- Sunday, 26 April 2026, at 5:58 p.m.
  • Severe crunch possibility but opponent has 4 on bar
    John O'Hagan -- Sunday, 26 April 2026, at 6:10 p.m.
  • Severe crunch possibility but opponent has 4 on bar
    Frank Berger -- Sunday, 26 April 2026, at 10:26 p.m.
  • Severe crunch possibility but opponent has 4 on bar
    Stick -- Monday, 27 April 2026, at 12:07 a.m.
    • Severe crunch possibility but opponent has 4 on bar
      ah_clem -- Monday, 27 April 2026, at 12:34 p.m.
    • Severe crunch possibility but opponent has 4 on bar
      John O'Hagan -- Monday, 27 April 2026, at 1:58 p.m.
  • Severe crunch possibility but opponent has 4 on bar
    ah_clem -- Monday, 27 April 2026, at 12:25 p.m.
  • Rollout and Comments
    Bob Koca -- Tuesday, 28 April 2026, at 6:22 p.m.