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Fairly ordinary early 41 @ 5a5a -- ROLLOUTS of Variant and Original

Posted By: Nack Ballard
Date: Saturday, 8 July 2017, at 3:59 a.m.

In Response To: Fairly ordinary early 41 @ 5a5a -- VARIANT (Nack Ballard)

		White is Player 2 score: 0 pip: 144 5 point match pip: 147 score: 0 Blue is Player 1
XGID=-a---BE-C-A-dBa-ab-d-b-AA-:0:0:1:41:0:0:0:5:10
Variant position (Blue's blot is on 10pt)

1.	Rollout1	6/1*	eq: -0.204
	Player: Opponent: 44.33% (G:16.56% B:0.86%) 55.67% (G:17.23% B:1.32%) Conf.: ± 0.008 (-0.212...-0.197) - [100.0%] Duration: 31 minutes 31 seconds
2.	Rollout1	10/5	eq: -0.235 (-0.030)
	Player: Opponent: 43.78% (G:14.49% B:0.52%) 56.22% (G:16.18% B:0.78%) Conf.: ± 0.006 (-0.241...-0.228) - [0.0%] Duration: 26 minutes 26 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 51521755 Moves: 3-ply, cube decisions: XG Roller

In my variant position above, Blue's near-side blot is on the 10pt. According to the 5k rollout, hitting is better than playing a checker to the 5pt (10/5) by .030.

In (my 5k rollout of) ah_clem's original position below, Blue's near-side blot is on the 9pt. Playing two checkers to the 5pt is better than hitting by .051.

By simple addition, the swing in play margin between these two positions is .030 + .051 = .081.

It is instructive to cross-compare same-type plays:

The superior play of the above variant position (equity = –.0204) is better than the inferior play of the original position (equity = –.234), even though both hit on the 1pt. The former play ends up with a 10pt blot (which is hit only with 64 and has a double shot against 63 54), whereas the latter ends up with a more vulnerable 9pt blot (which is hit with 63 54 and has only a single shot against 64). The value of this difference is .030.

The superior play of the original position below (equity = .184), by virtue of the better 5pt/6pt builder distribution (four checkers on each point), beats the inferior play of the variant position above (equity = –.0235) that ends up with three checkers on the 5pt and five on the 6pt. The value of this difference (difference in equities) is .051.

In short: (a) If Blue hits on the 1pt, having a 10pt blot beats having a 9pt blot by .030.
............. (b) If Blue plays in, the four-four 5pt/6pt distribution beats three-five by .051.

[As a double check, if you add the .030 to the .051, you get .081, which is the same as the margin swing between plays (cited in the third paragraph). It is coincidence that the .030 and .051 components of the .081 are the same for both reconciliations.]

Nack

		White is Player 2 score: 0 pip: 144 5 point match pip: 146 score: 0 Blue is Player 1
XGID=-a---BE-CA--dBa-ab-d-b-AA-:0:0:1:41:0:0:0:5:10
Original position (Blue's blot is on 9pt)

1.	Rollout1	9/5 6/5	eq: -0.184
	Player: Opponent: 44.63% (G:15.51% B:0.66%) 55.37% (G:15.86% B:0.83%) Conf.: ± 0.007 (-0.190...-0.177) - [100.0%] Duration: 29 minutes 59 seconds
2.	Rollout1	6/1*	eq: -0.234 (-0.051)
	Player: Opponent: 43.46% (G:16.38% B:0.81%) 56.54% (G:17.21% B:1.27%) Conf.: ± 0.007 (-0.241...-0.227) - [0.0%] Duration: 34 minutes 44 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 51521755 Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

Messages In This Thread

• Fairly ordinary early 41 @ 5a5a
  ah_clem -- Thursday, 6 July 2017, at 6:49 p.m.
  • Fairly ordinary early 41 @ 5a5a
    Karol Szczerek -- Thursday, 6 July 2017, at 7:25 p.m.
    • Fairly ordinary early 41 @ 5a5a
      neilkaz -- Friday, 7 July 2017, at 1:23 a.m.
  • Fairly ordinary early 41 @ 5a5a -- VARIANT
    Nack Ballard -- Thursday, 6 July 2017, at 11:05 p.m.
    • Fairly ordinary early 41 @ 5a5a -- VARIANT
      ah_clem -- Saturday, 8 July 2017, at 12:31 a.m.
    • Fairly ordinary early 41 @ 5a5a -- ROLLOUTS of Variant and Original
      Nack Ballard -- Saturday, 8 July 2017, at 3:59 a.m.
  • Fairly ordinary early 41 @ 5a5a Rollout
    ah_clem -- Saturday, 8 July 2017, at 12:34 a.m.