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32S-64H-41$-62 *** Rollouts by XG and GnuBg ***

Posted By: Taper_Mike
Date: Saturday, 24 March 2012, at 3:44 a.m.

In Response To: Conflicting Evals of 32S-64H-41$-62 (Taper_Mike)

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All notions of “nexting” this position need to be set aside. As the rollouts below demonstrate, this one is TCTC, albeit after only 10k. The bots did a cute reversal, so that XG is the one that now favors moving up, but at least XG and GnuBg seem to be converging on a similar result. Instinctually, I have a strong preference for slotting the 11pt. The opponent is favored to make his 5pt, and when he does, he cannot simultaneously hit outside. This seems like a fine opportunity to unstack the midpoint, and create some point making numbers of my own. In case my opponent decides to hit my blot on the 11pt, he cannot cover his own blot on his 5pt at the same time. So, what is wrong with my instincts? Over the board, and divorced in time from these rollouts, I am sure my analysis would be the same. This, when my instincts should tell me the two moves are close. To the extent that the cubeless numbers mean anything, the biggest difference between the two plays is the number of gammons lost. D (Down) loses more than 1% fewer cubeless gammons than Z (Reverse split). Rollouts from both XG and GnuBg follow. Mike

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eXtreme Gammon – 32S-64H-41$-62 – [Z D0.8] – "<=10

White is Player 2 score: 0 pip: 171 Unlimited Game Jacoby Beaver pip: 157 score: 0 Blue is Player 1 XGID=-a--b-E-C---dEA--c-da---A-:0:0:1:62:0:0:3:0:10 Blue to play 62

1. Rollout1 24/22 14/8 eq: -0.0040 Player: Opponent: 50.52% (G:12.06% B:0.52%) 49.48% (G:15.09% B:0.47%) Conf.: ±0.0056 (-0.0095...+0.0016) - [58.3%] Duration: 5 hours 30 minutes 2. Rollout1 14/8 13/11 eq: -0.0048 (-0.0008) Player: Opponent: 50.47% (G:11.99% B:0.51%) 49.53% (G:14.00% B:0.47%) Conf.: ±0.0056 (-0.0104...+0.0008) - [41.7%] Duration: 5 hours 15 minutes 1 10368 Games rolled with Variance Reduction. Dice Seed: 30829797 Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.03

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GNU Backgammon – 32S-64H-41$-62 – [D Z2.8] – /10

#		Ply	Move	Equity
•	1	R	14/8 13/11	-0.0048
			0.5052 0.1195 0.0050 - 0.4948 0.1389 0.0047 -0.0087 -0.0048 0.0006 0.0006 0.0002 - 0.0006 0.0007 0.0002 0.0016 0.0043
			Full cubeful rollout with var.redn.
			10368 games, Mersenne Twister dice gen. with seed 910288762 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	24/22 14/8	-0.0076 ( -0.0028)
			0.5052 0.1183 0.0055 - 0.4948 0.1467 0.0048 -0.0173 -0.0076 0.0006 0.0006 0.0002 - 0.0006 0.0007 0.0002 0.0018 0.0043
			Full cubeful rollout with var.redn.
			10369 games, Mersenne Twister dice gen. with seed 910288762 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

GNU Backgammon 0.90-mingw 20111003 (HTML Export version 1.226)

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Explanation of nacbracs

Messages In This Thread

• Conflicting Evals of 32S-64H-41$-62
  Taper_Mike -- Friday, 23 March 2012, at 12:08 a.m.
  • Conflicting Evals of 32S-64H-41$-62
    Stick -- Friday, 23 March 2012, at 7:58 a.m.
    • Conflicting Evals of 32S-64H-41$-62
      Taper_Mike -- Friday, 23 March 2012, at 8:27 a.m.
      • Conflicting Evals of 32S-64H-41$-62
        Stick -- Friday, 23 March 2012, at 8:47 a.m.
        • Conflicting Evals of 32S-64H-41$-62
          Casper van der Tak -- Friday, 23 March 2012, at 9:07 a.m.
  • 32S-64H-41$-62 *** Rollouts by XG and GnuBg ***
    Taper_Mike -- Saturday, 24 March 2012, at 3:44 a.m.
    • 32S-64H-41$-62 — Unlimited Games — XG2 3-ply Rollout
      Taper_Mike -- Thursday, 3 May 2012, at 10:13 p.m.
  • Conflicting Evals of 32S-64H-41$-62
    Timothy Chow -- Saturday, 31 March 2012, at 12:56 a.m.