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prime vs prime 31 - ROLLOUT & more VARIANTS

Posted By: Nack Ballard
Date: Monday, 4 December 2017, at 9:10 p.m.

In Response To: prime vs prime 31 - ROLLOUT & more (Karol Szczerek)

		White is Player 2 score: 0 pip: 135 Unlimited Game pip: 143 score: 0 Blue is Player 1
XGID=--bBBBB-A----D-a-ccdb--AA-:0:0:1:31:0:0:0:0:10
Original position

1.	Rollout1	24/21 13/12	eq: -0,162
	Player: Opponent: 48,06% (G:15,57% B:1,01%) 51,94% (G:24,33% B:2,26%) Conf.: ± 0,007 (-0,169...-0,155) - [69,4%] Duration: 36 minutes 38 seconds
2.	Rollout1	24/23 13/10	eq: -0,165 (-0,003)
	Player: Opponent: 45,69% (G:13,36% B:0,61%) 54,31% (G:15,75% B:0,88%) Conf.: ± 0,008 (-0,173...-0,157) - [30,6%] Duration: 31 minutes 38 seconds
3.	Rollout2	23/22 13/10	eq: -0,222 (-0,060)
	Player: Opponent: 45,95% (G:13,84% B:0,78%) 54,05% (G:23,17% B:1,92%) Conf.: ± 0,014 (-0,236...-0,208) - [0,0%] Duration: 8 minutes 22 seconds
4.	Rollout2	23/22 8/5	eq: -0,238 (-0,076)
	Player: Opponent: 44,91% (G:13,03% B:0,57%) 55,09% (G:20,28% B:0,71%) Conf.: ± 0,014 (-0,252...-0,224) - [0,0%] Duration: 7 minutes 55 seconds
5.	Rollout2	24/21 23/22	eq: -0,253 (-0,091)
	Player: Opponent: 45,09% (G:13,39% B:0,74%) 54,91% (G:25,49% B:1,17%) Conf.: ± 0,017 (-0,270...-0,236) - [0,0%] Duration: 7 minutes 35 seconds
6.	Rollout2	13/12 13/10	eq: -0,275 (-0,113)
	Player: Opponent: 45,40% (G:14,11% B:0,76%) 54,60% (G:25,32% B:3,02%) Conf.: ± 0,015 (-0,289...-0,260) - [0,0%] Duration: 8 minutes 17 seconds
1 5184 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller 2 1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller

Karol's rollout of his original position is copied above. S (Split, 24/21 13/12) is tied with z (reverse split, 24/23 13/10).

In addition to Karol's insightful notes, I'll add that if Blue plays S and White points on her 4pt, Blue's 4s and 5s (fanning) are diversified with his offensive covers (13/8 and 12/8).

I have a minor nitpick: If Blue instead blunders with the worse-than-it-may-look Z (reverse split, 23/22 13/10), it seems to me that none of White's 5s play weakly. Looked at more positively, I concur with and enhance Karol's main point that stepping up to the 21pt rather than the 22pt gives White a garbage pile of poor 5s she wouldn't otherwise have [by duplicating 6s instead]. Even in the case that she rolls 51 (hitting 23/17*), Blue's 4s, 5s and 6s hit back.

Through his variants, Karol demonstrated how sensitive White's builder position is, by altering her offense (a) 8/5 or (b) 10/9, which led to "z" (24/23 13/10) being easily best. I'm going to try moving her position the other way, backwards:

Let's nudge a White 6pt checker back to her 7pt (so that there are four on her 7pt and three on her 6pt instead of the inverse). How big a difference can that really make to Blue's 31 play? Check out Variant 1:

		White is Player 2 score: 0 pip: 136 Unlimited Game Jacoby Beaver pip: 143 score: 0 Blue is Player 1
XGID=--bBBBB-A----D-a-cdcb--AA-:0:0:1:31:0:0:3:0:10
Variant 1 (One of White's 6pt spares is back on her 7pt)

1.	Rollout1	24/21 13/12	eq: -0.134
	Player: Opponent: 48.39% (G:15.65% B:0.95%) 51.61% (G:21.85% B:1.65%) Conf.: ± 0.006 (-0.141...-0.128) - [100.0%] Duration: 8 minutes 09 seconds
2.	Rollout1	24/23 13/10	eq: -0.180 (-0.046)
	Player: Opponent: 45.28% (G:12.93% B:0.59%) 54.72% (G:15.63% B:0.83%) Conf.: ± 0.008 (-0.188...-0.173) - [0.0%] Duration: 9 minutes 43 seconds
3.	Rollout1	23/22 13/10	eq: -0.187 (-0.053)
	Player: Opponent: 46.56% (G:14.24% B:0.84%) 53.44% (G:20.62% B:1.60%) Conf.: ± 0.008 (-0.195...-0.180) - [0.0%] Duration: 9 minutes 23 seconds
4.	Rollout1	23/22 8/5	eq: -0.205 (-0.070)
	Player: Opponent: 44.97% (G:12.65% B:0.59%) 55.03% (G:17.58% B:0.72%) Conf.: ± 0.007 (-0.212...-0.197) - [0.0%] Duration: 9 minutes 41 seconds
5.	Rollout1	24/21 23/22	eq: -0.206 (-0.072)
	Player: Opponent: 46.01% (G:13.46% B:0.72%) 53.99% (G:22.48% B:1.10%) Conf.: ± 0.007 (-0.213...-0.199) - [0.0%] Duration: 8 minutes 33 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 86174152 Moves: 3-ply, cube decisions: XG Roller

Blue was emboldened by the weakening of White's 11, 33 and some sequences.

Another issue is timing. Say Blue makes a deep anchor and subsequently covers his 8pt. Which side will crack first? Let's move Blue's 13pt stack back to his 14pt to see if that makes a difference. In the original position, "S" and "z" are tied. How about with the change of 13/14(4) shown in Variant 2 below?

		White is Player 2 score: 0 pip: 135 Unlimited Game Jacoby Beaver pip: 147 score: 0 Blue is Player 1
XGID=--bBBBB-A-----Da-ccdb--AA-:0:0:1:31:0:0:3:0:10
Variant 2 (Compared to original, Blue owns his 14pt instead of 13pt)

1.	Rollout1	24/23 14/11	eq: -0.120
	Player: Opponent: 46.83% (G:13.46% B:0.60%) 53.17% (G:15.62% B:0.85%) Conf.: ± 0.009 (-0.129...-0.111) - [100.0%] Duration: 11 minutes 11 seconds
2.	Rollout1	24/21 14/13	eq: -0.171 (-0.051)
	Player: Opponent: 47.27% (G:13.90% B:0.78%) 52.73% (G:24.12% B:1.71%) Conf.: ± 0.007 (-0.179...-0.164) - [0.0%] Duration: 9 minutes 23 seconds
3.	Rollout1	14/13 14/11	eq: -0.190 (-0.070)
	Player: Opponent: 46.66% (G:14.26% B:0.77%) 53.34% (G:23.82% B:2.47%) Conf.: ± 0.008 (-0.199...-0.182) - [0.0%] Duration: 9 minutes 37 seconds
4.	Rollout1	23/22 14/11	eq: -0.205 (-0.085)
	Player: Opponent: 46.24% (G:13.90% B:0.76%) 53.76% (G:24.14% B:1.79%) Conf.: ± 0.008 (-0.213...-0.197) - [0.0%] Duration: 9 minutes 58 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 34514706 Moves: 3-ply, cube decisions: XG Roller

Finally, you'll find a bonus variant below, where a new play tops the rollout.

Nack

		White is Player 2 score: 0 pip: 135 Unlimited Game Jacoby Beaver pip: 139 score: 0 Blue is Player 1
XGID=-Bb-BBB-A----D-a-ccdb--AA-:0:0:1:31:0:0:3:0:10
Variant 3 (Compared to original, Blue owns his 1pt instead of his 3pt)

1.	Rollout1	23/22 8/5	eq: -0.554
	Player: Opponent: 36.48% (G:10.57% B:0.36%) 63.52% (G:22.63% B:0.94%) Conf.: ± 0.006 (-0.560...-0.548) - [82.5%] Duration: 7 minutes 08 seconds
2.	Rollout1	24/23 13/10	eq: -0.558 (-0.004)
	Player: Opponent: 34.82% (G:10.18% B:0.29%) 65.18% (G:18.16% B:0.94%) Conf.: ± 0.007 (-0.565...-0.552) - [17.5%] Duration: 8 minutes 00 second
3.	Rollout1	24/21 13/12	eq: -0.576 (-0.022)
	Player: Opponent: 37.16% (G:11.87% B:0.45%) 62.84% (G:27.86% B:2.57%) Conf.: ± 0.010 (-0.586...-0.566) - [0.0%] Duration: 9 minutes 31 seconds
4.	Rollout1	23/22 13/10	eq: -0.642 (-0.088)
	Player: Opponent: 36.03% (G:11.39% B:0.49%) 63.97% (G:27.57% B:2.31%) Conf.: ± 0.010 (-0.652...-0.632) - [0.0%] Duration: 9 minutes 01 second
1 5184 Games rolled with Variance Reduction. Dice Seed: 34514706 Moves: 3-ply, cube decisions: XG Roller

Messages In This Thread

• prime vs prime 31
  Karol Szczerek -- Friday, 1 December 2017, at 7:55 p.m.
  • prime vs prime 31
    ah_clem -- Friday, 1 December 2017, at 8:55 p.m.
    • prime vs prime 31
      ah_clem -- Friday, 1 December 2017, at 8:58 p.m.
  • prime vs prime 31
    Neil Robins -- Friday, 1 December 2017, at 9:59 p.m.
    • prime vs prime 31
      John O'Hagan -- Saturday, 2 December 2017, at 5:15 a.m.
  • prime vs prime 31 - ROLLOUT & more
    Karol Szczerek -- Monday, 4 December 2017, at 7:16 p.m.
    • prime vs prime 31 - ROLLOUT & more VARIANTS
      Nack Ballard -- Monday, 4 December 2017, at 9:10 p.m.