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Rollout: Double hit?

Posted By: Timothy Chow
Date: Monday, 12 September 2011, at 11:17 p.m.

In Response To: Double hit? (Timothy Chow)

XG 3-ply runs here, and a full rollout confirms that the double hit is a big mistake.

		White is Player 1 score: 0 pip: 103 Money session Jacoby Beaver pip: 136 score: 0 Blue is Player 2
XGID=-BaB-CBaB-------Ab-dbbBabA:2:1:1:62:0:0:3:0:10
Blue to play 62

1.	Rollout1	Bar/23* 22/16	eq: +0.523
	Player: Opponent: 57.36% (G:27.22% B:1.56%) 42.64% (G:19.97% B:0.77%) Conf: ± 0.011 (+0.512...+0.534) Duration: 3 hours 25 minutes
2.	Rollout1	Bar/23* 8/2*	eq: +0.472 (-0.051)
	Player: Opponent: 57.94% (G:29.68% B:1.57%) 42.06% (G:19.82% B:1.32%) Conf: ± 0.006 (+0.466...+0.478) Duration: 1 hour 52 minutes
3.	XG Roller+	Bar/23* 16/10	eq: +0.396 (-0.127)
	Player: Opponent: 53.27% (G:23.85% B:1.25%) 46.73% (G:16.57% B:0.86%)
1 5184 Games rolled with Variance Reduction. Dice Seed: 2 Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21

Had you going there, didn't I? I wasn't sure I believed this result, so I looked a bit closer. First I checked with GNU 2-ply, which double hits. Then I asked, what happens after double hit, dance? XG 3-ply cashes but XG 4-ply says it's too good. Let's see what happens if I change the rollout settings.

		White is Player 1 score: 0 pip: 103 Money session Jacoby Beaver pip: 136 score: 0 Blue is Player 2
XGID=-BaB-CBaB-------Ab-dbbBabA:2:1:1:62:0:0:3:0:10
Blue to play 62

1.	Rollout1	Bar/23* 8/2*	eq: +0.541
	Player: Opponent: 60.61% (G:34.90% B:1.81%) 39.39% (G:19.00% B:1.19%) Conf: ± 0.014 (+0.527...+0.555) Duration: 1 hour 07 minutes
2.	Rollout1	Bar/23* 22/16	eq: +0.478 (-0.062)
	Player: Opponent: 57.02% (G:26.49% B:1.56%) 42.98% (G:19.21% B:0.74%) Conf: ± 0.010 (+0.468...+0.488) Duration: 1 hour 31 minutes
3.	XG Roller+	Bar/23* 16/10	eq: +0.396 (-0.145)
	Player: Opponent: 53.27% (G:23.85% B:1.25%) 46.73% (G:16.57% B:0.86%)
1 1296 Games rolled with Variance Reduction. Dice Seed: 2 First 4 moves and cube decisions: 4 ply Remaining moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21

This fits my preconceived notions much better, so obviously I choose to believe the second rollout. That's how science works, right?

Messages In This Thread

• Double hit?
  Timothy Chow -- Sunday, 11 September 2011, at 10:09 p.m.
  • Double hit?
    Chris Yep -- Monday, 12 September 2011, at 10:12 a.m.
    • Double hit?
      Stick -- Monday, 12 September 2011, at 10:42 a.m.
      • Double hit?
        Casper van der Tak -- Monday, 12 September 2011, at 1:30 p.m.
  • Rollout: Double hit?
    Timothy Chow -- Monday, 12 September 2011, at 11:17 p.m.
    • XG2
      Michael Nielsen -- Tuesday, 13 September 2011, at 9:09 a.m.
    • Rollout: Double hit?
      neilkaz -- Tuesday, 13 September 2011, at 4:37 p.m.