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Correction (power rating)

Posted By: Nack Ballard
Date: Tuesday, 4 July 2017, at 2:53 a.m.

In Response To: Four Score position with 64 (Nack Ballard)

When calculating a power rating, any play that is not best at any of the four main scores should be bypassed/ignored. In the case of this R4, 10/6 7/1* is such a play (never best). Therefore, for gammon save (see rollout copied below), the .018 margin of best to third-best is used (rather than the best to second-best margin of .010.)

Thus, the correct power rating for this R4 is [sqrt 21 + sqrt 13*20/9 + sqrt 18*10/7 + sqrt 72*10/7] = 25.17.

Nack

		White is Player 2 score: 0 pip: 128 2 point match Crawford pip: 108 score: 1 Blue is Player 1
XGID=-aBBB-DA-AA--bbb--bbBb-b--:0:0:1:64:1:0:1:2:10
Gammon Save

1.	Rollout1	10/4 7/3	eq: -0.144
	Player: Opponent: 50.28% (G:13.49% B:0.33%) 49.72% (G:7.47% B:0.44%) Conf.: ± 0.001 (-0.145...-0.143) - [100.0%] Duration: 1 hour 28 minutes
2.	Rollout1	10/6 7/1*	eq: -0.154 (-0.010)
	Player: Opponent: 50.13% (G:16.23% B:0.32%) 49.87% (G:7.81% B:0.49%) Conf.: ± 0.001 (-0.155...-0.152) - [0.0%] Duration: 1 hour 44 minutes
3.	Rollout2	7/1* 6/2	eq: -0.162 (-0.018)
	Player: Opponent: 50.87% (G:18.09% B:0.32%) 49.13% (G:8.97% B:0.57%) Conf.: ± 0.003 (-0.165...-0.159) - [0.0%] Duration: 12 minutes 35 seconds
4.	Rollout2	9/3 7/3	eq: -0.169 (-0.025)
	Player: Opponent: 49.45% (G:13.65% B:0.48%) 50.55% (G:7.91% B:0.49%) Conf.: ± 0.003 (-0.172...-0.166) - [0.0%] Duration: 10 minutes 27 seconds
5.	Rollout2	10/4 9/5	eq: -0.172 (-0.028)
	Player: Opponent: 48.54% (G:15.45% B:0.29%) 51.46% (G:7.12% B:0.37%) Conf.: ± 0.003 (-0.174...-0.169) - [0.0%] Duration: 12 minutes 30 seconds
6.	Rollout2	9/5 7/1*	eq: -0.177 (-0.033)
	Player: Opponent: 50.63% (G:20.66% B:0.49%) 49.37% (G:9.48% B:0.67%) Conf.: ± 0.003 (-0.180...-0.174) - [0.0%] Duration: 12 minutes 43 seconds
1 41472 Games rolled with Variance Reduction. Dice Seed: 85506921 Moves: 3-ply, cube decisions: XG Roller 2 5184 Games rolled with Variance Reduction. Dice Seed: 85506921 Moves: 3-ply, cube decisions: XG Roller

Messages In This Thread

• Four Score position with 64
  Nack Ballard -- Tuesday, 4 July 2017, at 2:15 a.m.
  • Correction (power rating)
    Nack Ballard -- Tuesday, 4 July 2017, at 2:53 a.m.
  • Four Score position with 64
    Paul Weaver -- Tuesday, 4 July 2017, at 12:42 p.m.
    • Cube location
      Nack Ballard -- Tuesday, 4 July 2017, at 9:29 p.m.