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What's a fish do here? ***ROLLOUT the barrel***

Posted By: Daniel Murphy
Date: Monday, 6 February 2012, at 7:17 p.m.

In Response To: What's a fish do here? (Daniel Murphy)

Money game. Blue on roll.

White	63
Blue	85
Position ID: 720GAECbtwOgAA Match ID: UQkAAAAAAAAE

Cube decision
Rollout cubeless equity		+0.6157
Cubeful equities:
1.	Double, pass	+1.0000
2.	Double, take	+1.1508	+0.1508
3.	No double	+0.8757	-0.1243
Proper cube action:		Redouble, pass
Rollout details
Win W g W bg Lose L g L bg Cubeless Cubeful Player Blue owns 2-cube 0.7997 0.0214 0.0004 - 0.2003 0.0054 0.0000 +0.6157 +0.8757 Standard error 0.0004 0.0004 0.0000 - 0.0004 0.0002 0.0001 0.0010 0.0018 Player White owns 4-cube 0.8123 0.0189 0.0004 - 0.1877 0.0045 0.0000 +1.2787 +1.1508 Standard error 0.0007 0.0006 0.0000 - 0.0007 0.0003 0.0001 0.0030 0.0040
Full cubeful rollout with var.redn.
1296 games, Mersenne Twister dice gen. with seed 906073840 and quasi-random dice
Play: supremo 2-ply cubeful prune [world class]
keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
Skip pruning for 1-ply moves.
Cube: 2-ply cubeful prune [world class]

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This is a pretty big pass. Whether it's helpful or not I don't know, but since this is a money game rollout, from the cubeful equity we can calculate a cubeless, gammon-adjusted win percentage:

CF 1.1508 / 2 = 0.5754. 0.5754 / 2 = 0.2877. 0.2877 + .5000 = 0.7877 = 78.77% (that is, 3.77% more than the 75% take/pass point in a cubeless, gammonless game).

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Using Gnubg's "Statistics" feature, after double/take:

(1) Blue actually won 78.32% of all games (not the "cubeless" 81.23%), including 1.62% gammons (21 gammons in 1296 trials).

(2) White actually won 21.68% of all games (not the "cubeless" 18.77%), of which 14.58% were 4-cube wins (14.35% single, 0.15% gammons, 0.07% backgammons) and 7.1% on a higher level (almost all on the 8-cube level).

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Annotation

2-ply cubeless equity +0.5706
0.7761 0.0234 0.0004 - 0.2239 0.0055 0.0000
Cubeful equities:
1. Double, take +0.9890
2. Double, pass +1.0000 ( +0.0110)
3. No double +0.8385 ( -0.1505)
Proper cube action: Redouble, take

3-ply cubeless equity +0.5910
0.7855 0.0277 0.0000 - 0.2145 0.0078 0.0000
Cubeful equities:
1. Double, pass +1.0000
2. Double, take +1.0341 ( +0.0341)
3. No double +0.8556 ( -0.1444)
Proper cube action: Redouble, pass

4-ply cubeless equity +0.5984
0.7913 0.0203 0.0004 - 0.2087 0.0048 0.0000
Cubeful equities:
1. Double, pass +1.0000
2. Double, take +1.0566 ( +0.0566)
3. No double +0.8528 ( -0.1472)
Proper cube action: Redouble, pass

Messages In This Thread

• What's a fish do here?
  Daniel Murphy -- Sunday, 5 February 2012, at 11:26 p.m.
  • What's a fish do here?
    Stick -- Sunday, 5 February 2012, at 11:42 p.m.
    • What's a fish do here?
      Daniel Murphy -- Monday, 6 February 2012, at 12:12 a.m.
  • What's a fish do here?
    Sebastiaan Kuijs -- Monday, 6 February 2012, at 1:35 a.m.
  • What's a fish do here?
    David Rockwell -- Monday, 6 February 2012, at 5:55 a.m.
  • What's a fish do here?
    higonefive -- Monday, 6 February 2012, at 8:41 a.m.
  • What's a fish do here?
    neilkaz -- Monday, 6 February 2012, at 4:39 p.m.
  • What's a fish do here? ***ROLLOUT the barrel***
    Daniel Murphy -- Monday, 6 February 2012, at 7:17 p.m.
    • Rollouts of variants
      Daniel Murphy -- Wednesday, 8 February 2012, at 11:59 p.m.
  • What's a fish do here?
    ah_clem -- Monday, 6 February 2012, at 9:21 p.m.