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Backgame play decision

Posted By: Ian Dunstan
Date: Monday, 6 July 2009, at 11:07 a.m.

The score (after 0 games) is: White 0, Blue 0 (match to 3 points)

Move number 20: Blue to play 31

White	118
Blue	217
Position ID: 2LYjBwDQGhzANg Match ID: cIllAAAAAAAA

• Blue moves 23/22 8/5

Cube decision
2-ply cubeless equity		-0.9804	(Money: -0.7156)
	34.45 1.94 0.02 - 65.55 36.73 5.68
Cubeful equities:
1.	No double	-1.0097
2.	Double, pass	+1.0000	+2.0097
3.	Double, take	-1.7967	-0.7871
Proper cube action:		No double, take (28.1%)

My play was 17th on Gnubg's 2-ply list and rated a whopper with extras, but I really doubt it is so. Gnubg's top 2-ply choice was the reasonable 8/4. I also included 13/10 8/7, since I remember looking at this play briefly during the actual match. Note that there is nothing remotely close to stat. sig. in my rollout so far.

What is your pick?

Maybe someone can spin a few CPU cycles with XG and see what it comes up with. I will run my rollout through to 1296.

#		Ply	Move	Equity
•	1	R	23/22 8/5	-0.5597
			44.16 3.85 0.38 - 55.84 34.84 12.75 -0.5938 -0.5597 0.86 0.34 0.19 - 0.86 0.91 1.22 0.0319 0.0699
			Full cubeful rollout with var.redn.
			360 games, Mersenne Twister dice gen. with seed 863863827 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	13/10 8/7	-0.5835 ( -0.0238)
			42.91 3.48 0.49 - 57.09 35.76 10.94 -0.5765 -0.5835 0.62 0.38 0.77 - 0.62 0.72 1.11 0.0262 0.0504
			Full cubeful rollout with var.redn.
			360 games, Mersenne Twister dice gen. with seed 863863827 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	8/4	-0.6337 ( -0.0740)
			42.65 4.47 0.46 - 57.35 36.62 12.11 -0.6399 -0.6337 0.82 0.40 0.34 - 0.82 0.93 1.29 0.0380 0.0661
			Full cubeful rollout with var.redn.
			360 games, Mersenne Twister dice gen. with seed 863863827 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]
	4	2	7/4 6/5	-0.5427 ( +0.0170)
			45.51 2.35 0.02 - 54.49 31.31 7.18
	5	2	13/9	-0.5501 ( +0.0096)
			45.44 2.10 0.01 - 54.56 31.45 7.19
	6	2	13/10 6/5	-0.5512 ( +0.0085)
			45.34 2.20 0.02 - 54.66 31.42 7.18

Messages In This Thread

• Backgame play decision
  Ian Dunstan -- Monday, 6 July 2009, at 11:07 a.m.
  • Backgame play decision
    Stick -- Monday, 6 July 2009, at 11:37 a.m.
    • Backgame play decision
      Chuck Bower -- Monday, 6 July 2009, at 9:44 p.m.
      • Backgame play decision
        Matt Cohn-Geier -- Monday, 6 July 2009, at 10:06 p.m.
        • Backgame play decision
          Chuck Bower -- Tuesday, 7 July 2009, at 1:17 p.m.
    • Backgame play decision
      Ian Dunstan -- Tuesday, 7 July 2009, at 6:46 a.m.
      • Backgame play decision
        Petter Bengtsson -- Tuesday, 7 July 2009, at 12:38 p.m.
  • Backgame play decision
    Stein Kulseth -- Monday, 6 July 2009, at 1:41 p.m.
  • Backgame play decision
    Rich Munitz -- Monday, 6 July 2009, at 2:54 p.m.
  • Backgame play decision
    neilkaz -- Tuesday, 7 July 2009, at 12:24 a.m.
  • Backgame play decision
    Christian Munk-Christensen -- Wednesday, 8 July 2009, at 7:55 p.m.