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Miran's backgame position, take 2

Posted By: Timothy Chow
Date: Saturday, 16 June 2012, at 4:37 p.m.

I spent some time trying to analyze Miran's backgame position. This wasn't easy because XG version 1.21 doesn't understand the position very well (XGR+ and 4-ply dissented quite a bit as I varied the position). However, the two variants below seem interesting. I don't trust the XG1 truncated rollouts here, but if Miran (or someone else) rolls them out with stronger settings and more candidate plays, then we'll at least have some more relevant data to chew on.

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		White is Player 2 score: 0 pip: 187 Money session Jacoby Beaver pip: 142 score: 0 Blue is Player 1
XGID=-aaaBbCBCB--bA--ba-c-bA--A:0:0:1:23:0:0:3:0:10
Blue to play 23

1.	Rollout1	Bar/23 6/3*	eq: +0.431
	Player: Opponent: 57.67% (G:23.65% B:1.81%) 42.33% (G:10.39% B:0.58%) Conf: ± 0.013 (+0.418...+0.444) Duration: 7 minutes 25 seconds
2.	Rollout1	Bar/22 8/6	eq: +0.381 (-0.050)
	Player: Opponent: 56.53% (G:24.17% B:1.75%) 43.47% (G:10.13% B:0.44%) Conf: ± 0.013 (+0.368...+0.394) Duration: 6 minutes 46 seconds
3.	Rollout1	Bar/20	eq: +0.351 (-0.080)
	Player: Opponent: 56.17% (G:22.67% B:1.88%) 43.83% (G:10.61% B:0.50%) Conf: ± 0.013 (+0.338...+0.364) Duration: 6 minutes 40 seconds
1 Truncated at 7 moves using 3 ply. 648 Games rolled with Variance Reduction. Dice Seed: 2 First 2 moves and cube decisions: 3 ply Remaining moves: 2 ply, cube decisions: 3 ply

eXtreme Gammon Version: 1.21

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		White is Player 2 score: 0 pip: 187 Money session Jacoby Beaver pip: 142 score: 0 Blue is Player 1
XGID=-aaaBbCBCB--bA-a-b-c-bA--A:0:0:1:23:0:0:3:0:10
Blue to play 23

1.	Rollout1	Bar/20	eq: +0.434
	Player: Opponent: 57.65% (G:23.21% B:1.71%) 42.35% (G:9.24% B:0.40%) Conf: ± 0.012 (+0.422...+0.446) Duration: 7 minutes 14 seconds
2.	Rollout1	Bar/22 8/6	eq: +0.423 (-0.012)
	Player: Opponent: 57.63% (G:23.84% B:1.70%) 42.37% (G:9.49% B:0.41%) Conf: ± 0.011 (+0.412...+0.434) Duration: 6 minutes 52 seconds
3.	Rollout1	Bar/23 6/3*	eq: +0.374 (-0.060)
	Player: Opponent: 57.00% (G:22.37% B:1.64%) 43.00% (G:10.55% B:0.54%) Conf: ± 0.012 (+0.362...+0.386) Duration: 8 minutes 20 seconds
1 Truncated at 7 moves using 3 ply. 648 Games rolled with Variance Reduction. Dice Seed: 2 First 2 moves and cube decisions: 3 ply Remaining moves: 2 ply, cube decisions: 3 ply

eXtreme Gammon Version: 1.21

Messages In This Thread

• Miran's backgame position, take 2
  Timothy Chow -- Saturday, 16 June 2012, at 4:37 p.m.
  • Miran's backgame position, take 2
    Daniel Murphy -- Saturday, 16 June 2012, at 6:28 p.m.
  • I'll do the rollouts *NM*
    mtuhtan -- Sunday, 17 June 2012, at 7:05 a.m.
  • Rollouts
    mtuhtan -- Tuesday, 19 June 2012, at 7:09 p.m.
    • Rollouts
      Timothy Chow -- Wednesday, 20 June 2012, at 3:45 p.m.