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Cyprus: Grand Final, containment game

Posted By: Daniel Murphy
Date: Tuesday, 6 December 2011, at 8:21 p.m.

In Response To: Cyprus: Grand Final, containment game (Martin Sterel)

Martin's question is: Why does XG Roller++ prefer bar/15 over bar/19 11/7 in a money game with a centered cube?

For the life of me I have no idea. Note that the XG Roller++ displays shows "cubeless" game breakdowns but only cubeful equities. It would be useful to also see the "cubeless" equities, but I assume that the differences between "cubeless" and cubeful equities in the XG Roller++ result are similar to those in the two Gnubg rollouts below (which unlike XG Roller++ have bar/19 11/7 ahead but the two plays are very close).

(1) In all three rollouts, bar/19 11/7 wins more "cubeless" games, wins more "cubeless" gammons, and loses fewer "cubeless" gammons.

(2) With or without Jacoby, these rollouts agree that bar/19 11/7 is much the better play "cubeless" but about even with bar/15 cubeful.

(3) I've found no White response to Blue's play that makes any difference in Blue's cube action next turn.

(4) Checking with the Gnubg Temperature Map, the only White responses for which bar/15 is better are 5-3 and 5-1. Blue is obviously not a favorite after 5-3, and after bar/19 ... 51 21/16 Gnubg does not double even though it has a triple shot. For White's other 32/36 rolls, bar/19 11/7 is better, according to the 2-ply Temperature Map.

---

Without the Jacoby Rule:

The score (after 0 games) is: White 0, MG 0

Move number 3: MG to play 46

White	53
MG	118
Position ID: 79sBAATGbrMAQA Match ID: cAkaAAAAAAAA

Cube decision
2-ply cubeless equity		-0.0149
	0.5395 0.0362 0.0000 - 0.4605 0.1298 0.0003
Cubeful equities:
1.	No double	+0.1159
2.	Double, pass	+1.0000	+0.8841
3.	Double, take	-0.2741	-0.3900
Proper cube action:		No double, beaver (30.6%)

#		Ply	Move	Equity
•	1	R	bar/19 11/7	+0.3920
			0.5956 0.0371 0.0005 - 0.4044 0.0508 0.0001 +0.1778 +0.3920 0.0005 0.0005 0.0001 - 0.0005 0.0007 0.0000 0.0014 0.0030
			Full cubeful rollout with var.redn.
			2592 games, Mersenne Twister dice gen. with seed 939511699 and quasi-random dice
			Play: world class 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 8 more moves within equity 0.16
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	bar/15	+0.3845 ( -0.0076)
			0.5738 0.0349 0.0005 - 0.4262 0.0694 0.0003 +0.1132 +0.3845 0.0005 0.0005 0.0001 - 0.0005 0.0010 0.0000 0.0015 0.0034
			Full cubeful rollout with var.redn.
			2592 games, Mersenne Twister dice gen. with seed 939511699 and quasi-random dice
			Play: world class 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 8 more moves within equity 0.16
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	3	R	bar/19 8/4*	+0.3482 ( -0.0438)
			0.6056 0.0362 0.0008 - 0.3944 0.1686 0.0009 +0.0788 +0.3482 0.0016 0.0010 0.0002 - 0.0016 0.0020 0.0002 0.0039 0.0096
			Full cubeful rollout with var.redn.
			324 games, Mersenne Twister dice gen. with seed 939511699 and quasi-random dice
			Play: world class 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 8 more moves within equity 0.16
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

With the Jacoby Rule:

The score (after 0 games) is: White 0, MG 0

Move number 3: MG to play 46

White	53
MG	118
Position ID: 79sBAATGbrMAQA Match ID: cAkaAAAAAAAA

• MG moves bar/19 11/7

#		Ply	Move	Equity
•	1	R	bar/19 11/7	+0.3909
			0.5953 0.0359 0.0006 - 0.4047 0.0511 0.0001 +0.1759 +0.3909 0.0005 0.0005 0.0001 - 0.0005 0.0007 0.0000 0.0014 0.0030
			Full cubeful rollout with var.redn.
			2593 games, Mersenne Twister dice gen. with seed 939139224 and quasi-random dice
			Play: world class 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 8 more moves within equity 0.16
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	bar/15	+0.3904 ( -0.0005)
			0.5752 0.0359 0.0004 - 0.4248 0.0702 0.0003 +0.1161 +0.3904 0.0005 0.0005 0.0001 - 0.0005 0.0010 0.0000 0.0015 0.0034
			Full cubeful rollout with var.redn.
			2592 games, Mersenne Twister dice gen. with seed 939139224 and quasi-random dice
			Play: world class 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 8 more moves within equity 0.16
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	3	2	bar/19 8/4*	+0.2894 ( -0.1015)
			0.6095 0.0476 0.0002 - 0.3905 0.1752 0.0018

Messages In This Thread

• Cyprus: Grand Final, containment game
  Klaus Evers -- Monday, 5 December 2011, at 7:57 p.m.
  • Cyprus: Grand Final, containment game
    Daniel Murphy -- Tuesday, 6 December 2011, at 1:48 a.m.
    • Cyprus: Grand Final, containment game
      Casper van der Tak -- Tuesday, 6 December 2011, at 6:57 a.m.
    • Cyprus: Grand Final, containment game
      Martin Sterel -- Tuesday, 6 December 2011, at 8:06 a.m.
    • Cyprus: Grand Final, containment game
      Martin Sterel -- Tuesday, 6 December 2011, at 8:12 a.m.
      • Cyprus: Grand Final, containment game
        Daniel Murphy -- Tuesday, 6 December 2011, at 8:21 p.m.
        • Cyprus: Grand Final, containment game
          Martin Sterel -- Wednesday, 7 December 2011, at 4:34 a.m.
  • Cyprus: Grand Final, containment game
    Timothy Chow -- Tuesday, 6 December 2011, at 5:06 p.m.
  • Cyprus: Grand Final, ** Rollout **
    Klaus Evers -- Sunday, 11 December 2011, at 10:10 p.m.