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52D-54D-21$-31 and variant

Posted By: Nack Ballard
Date: Friday, 4 November 2011, at 2:30 p.m.

In Response To: 52D-54D-21$-31 and variant (Casper van der Tak)

54D-21$-31

52D-54D-21$-31

The two key positions, which were diagrammed as the second pair at the bottom of this post, are shown above.

Left: . [H P18] ~5 (old Snowie rollout)
Right: [P H50] "<=5 (first XG rollout below)

In attempting to explain the difference of .068 between these P/H margins, I gave three reasons in my post (second set of bullets) and you gave two reasons in your post.

In order to try to roughly estimate the size of impact of your reasons, I rolled out a variant of the right-hand position in which one of White's two 11pt checkers is instead a fifth checker on her 8pt. The result is

[P H40] "<=5 (second XG rollout below)

On a quick and dirty analysis, your two reasons combined explain .010 of the .068 difference. There is variance in 5k rollouts, so it might be more or less (and the 3 pips affect chances in the priming battle), so take this recap for what it's worth. :)

Nack

		White is Player 2 score: 0 pip: 157 Unlimited Game Jacoby Beaver pip: 158 score: 0 Blue is Player 1
XGID=-b----E-DA--bCb--d-da---B-:0:0:1:31:0:0:3:0:10
52D-54D-21$-31

1.	Rollout1	8/5 6/5	eq: +0.128
	Player: Opponent: 52.72% (G:17.83% B:1.06%) 47.28% (G:14.15% B:0.82%) Conf.: ± 0.008 (+0.120...+0.137) - [100.0%] Duration: 5 hours 02 minutes
2.	Rollout1	24/20*	eq: +0.078 (-0.050)
	Player: Opponent: 51.05% (G:16.73% B:1.25%) 48.95% (G:13.05% B:0.68%) Conf.: ± 0.009 (+0.069...+0.087) - [0.0%] Duration: 6 hours 59 minutes
1 5184 Games rolled with Variance Reduction. Dice Seed: 724 Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.01

		White is Player 2 score: 0 pip: 154 Unlimited Game Jacoby Beaver pip: 158 score: 0 Blue is Player 1
XGID=-b----E-DA--bCa--e-da---B-:0:0:1:31:0:0:3:0:10
52D-54D-51$-31

1.	Rollout1	8/5 6/5	eq: +0.229
	Player: Opponent: 55.09% (G:18.73% B:1.19%) 44.91% (G:13.88% B:0.82%) Conf.: ± 0.008 (+0.220...+0.237) - [100.0%] Duration: 2 hours 01 minute
2.	Rollout1	24/20*	eq: +0.188 (-0.040)
	Player: Opponent: 53.49% (G:18.13% B:1.53%) 46.51% (G:12.66% B:0.63%) Conf.: ± 0.009 (+0.179...+0.197) - [0.0%] Duration: 2 hours 54 minutes
1 5184 Games rolled with Variance Reduction. Dice Seed: 724 Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.01

Messages In This Thread

• 31 to play
  rambiz -- Wednesday, 2 November 2011, at 7:10 p.m.
  • 31 to play
    christian munk-christensen -- Wednesday, 2 November 2011, at 7:43 p.m.
  • 52D-54D-21$-31
    Timothy Chow -- Wednesday, 2 November 2011, at 9:40 p.m.
    • 52D-54D-21$-31
      Nack Ballard -- Thursday, 3 November 2011, at 4:55 p.m.
      • 52D-54D-21$-31
        rambiz -- Thursday, 3 November 2011, at 9:00 p.m.
  • 31 to play
    Nack Ballard -- Thursday, 3 November 2011, at 4:35 p.m.
    • 31 to play
      Casper van der Tak -- Thursday, 3 November 2011, at 4:56 p.m.
      • 52D-54D-21$-31 and variant
        Nack Ballard -- Thursday, 3 November 2011, at 8:54 p.m.
        • 52D-54D-21$-31 and variant
          Casper van der Tak -- Thursday, 3 November 2011, at 9:14 p.m.
          • 52D-54D-21$-31 and variant
            Nack Ballard -- Friday, 4 November 2011, at 2:30 p.m.
            • 52D-54D-21$-31 and variant
              Casper van der Tak -- Friday, 4 November 2011, at 3:29 p.m.
    • 54D-21$-31 and 52D-54D-21$-31
      Nack Ballard -- Thursday, 3 November 2011, at 7:22 p.m.
    • 31 to play
      Timothy Chow -- Saturday, 5 November 2011, at 1:35 a.m.
      • 31 to play
        Nack Ballard -- Saturday, 5 November 2011, at 2:12 a.m.