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Blue to play 54 -- ROLLOUT and Variants

Posted By: Nack Ballard
Date: Thursday, 25 January 2018, at 12:45 a.m.

In Response To: Blue to play 54 (Nack Ballard)

		White is Player 2 score: 0 pip: 77 Unlimited Game Jacoby Beaver pip: 95 score: 0 Blue is Player 1
XGID=-BBBBBB------A-Aabacacbb-A:1:-1:1:54:0:0:3:0:10
Blue to play 54

1.	Rollout1	Bar/20* 15/11	eq: +1.566
	Player: Opponent: 96.26% (G:63.57% B:2.15%) 3.74% (G:0.01% B:0.00%) Conf.: ± 0.002 (+1.564...+1.567) - [100.0%] Duration: 37.1 seconds
2.	Rollout1	Bar/20* 13/9	eq: +1.561 (-0.005)
	Player: Opponent: 96.37% (G:62.84% B:2.12%) 3.63% (G:0.01% B:0.00%) Conf.: ± 0.002 (+1.559...+1.562) - [0.0%] Duration: 33.4 seconds
3.	Rollout1	Bar/20* 20/16*	eq: +1.558 (-0.008)
	Player: Opponent: 96.55% (G:63.14% B:1.13%) 3.45% (G:0.00% B:0.00%) Conf.: ± 0.002 (+1.557...+1.560) - [0.0%] Duration: 27.9 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 44579808 Moves: 3-ply, cube decisions: XG Roller

According to the rollout above, hitting twice is a hair worse (by. 008) than hitting once. Hitting twice loses 0.29% more games (more likely to get hit bearing off) but wins 0.43% extra gammons and 1.02% extra backgammons (by virtue of hitting the third checker more often than failing to hit a second checker).

If one of the floating checkers is nudged forward a pip, hitting twice wins the rollout by .002 (cusp). If the leading back checker is also back on the 15pt, hitting twice loses the rollout by .019. (Rollouts not shown.)

Below is a variant -- same concept -- that illustrates the danger of playing on autopilot. Hitting twice is a whopper with cheese, blowing 14% extra gammons and 2.3% extra backgammons.

Nack

		White is Player 2 score: 0 pip: 65 Unlimited Game Jacoby Beaver pip: 101 score: 0 Blue is Player 1
XGID=-BBBBBB----------Baead-caA:1:-1:1:61:0:0:3:0:10
Blue to play 61

1.	Rollout1	Bar/24* 17/11	eq: +1.588
	Player: Opponent: 97.12% (G:61.91% B:3.72%) 2.88% (G:0.04% B:0.00%) Conf.: ± 0.002 (+1.585...+1.590) - [100.0%] Duration: 3.0 seconds
2.	Rollout1	Bar/24* 24/18*	eq: +1.435 (-0.153)
	Player: Opponent: 97.59% (G:47.86% B:1.43%) 2.41% (G:0.00% B:0.00%) Conf.: ± 0.002 (+1.433...+1.437) - [0.0%] Duration: 2.4 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 32868897 Moves and cube decisions: 1-ply

Messages In This Thread

• Would you could you in a car?
  Stick -- Monday, 22 January 2018, at 3:02 p.m.
  • Would you could you in a car?
    neilkaz -- Monday, 22 January 2018, at 4:51 p.m.
  • Would you could you in a car?
    Michael -- Monday, 22 January 2018, at 5:22 p.m.
    • Would you could you in a car?
      Michael -- Monday, 22 January 2018, at 5:25 p.m.
      • Would you could you in a car?
        Michael -- Monday, 22 January 2018, at 6:15 p.m.
  • Would you could you in a car?
    Karol Szczerek -- Monday, 22 January 2018, at 6:14 p.m.
  • Would you could you in a car?
    Bob Koca -- Monday, 22 January 2018, at 7:59 p.m.
    • Would you could you in a car?
      Stick -- Tuesday, 23 January 2018, at 12:39 p.m.
  • Would you could you in a car? - Rollout
    Stick -- Tuesday, 23 January 2018, at 12:43 p.m.
    • Would you could you in a car? - Rollout
      hominid -- Tuesday, 23 January 2018, at 2:43 p.m.
      • Would you could you in a car? - Rollout
        Stick -- Tuesday, 23 January 2018, at 8:48 p.m.
    • Blue to play 54
      Nack Ballard -- Wednesday, 24 January 2018, at 7:37 p.m.
      • Blue to play 54
        Stick -- Wednesday, 24 January 2018, at 8:20 p.m.
      • Blue to play 54
        christian munk-christensen -- Wednesday, 24 January 2018, at 10:44 p.m.
        • Blue to play 54
          Stick -- Wednesday, 24 January 2018, at 10:56 p.m.
      • Blue to play 54 -- ROLLOUT and Variants
        Nack Ballard -- Thursday, 25 January 2018, at 12:45 a.m.
        • Blue to play 54 -- ROLLOUT and Variants
          Casper Van der Tak -- Thursday, 25 January 2018, at 8:39 a.m.
  • Would you could you in a car?
    ah_clem -- Wednesday, 24 January 2018, at 9:08 p.m.
  • Rollout w/o Jacoby
    ah_clem -- Wednesday, 24 January 2018, at 9:19 p.m.