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Payment due? -- Rollout

Posted By: Daniel Murphy
Date: Monday, 2 August 2010, at 9:25 p.m.

In Response To: Payment due? (Daniel Murphy)

Double Match Point. Blue to play 5-4

White	135
Blue	97
Position ID: ZOfBAwIz7g4GAA Match ID: cIkyAAAAAAAA

• Blue moves 13/9 13/8

I looked at my 38 pip lead, Opponent's soon to be covered homeboard blot, and the shortage of free checkers (five) after what I thought was the best "pay later" play -- the natural looking 8/4 7/2 -- and decided "pay now" might be slightly better.

13/9 13/8 is not the blunder the evaluation said it was, but it is (in this rollout) a 0.020 error. That may not seem like much, but in gammonless backgammon -0.020 means giving away 1% game winning chances.

I definitely underestimated Blue's chances in all variations -- If someone had told me that paying later wins nearly 79% of the time, I'd have definitely thought that paying now (and getting hit 30% of the time) couldn't be right.

Alert: doubtful move ( -0.020)

#		Ply	Move	Equity
	1	R	8/4 7/2	+0.5775
			0.7888 0.2850 0.0012 - 0.2112 0.0234 0.0007 +0.5775 +0.5775 0.0030 0.0184 0.0011 - 0.0030 0.0051 0.0009 0.0059 0.0059
			Full cubeful rollout with var.redn.
			364 games, Mersenne Twister dice gen. with seed 897034043 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	7/2 6/2	+0.5589 ( -0.0186)
			0.7795 0.3243 0.0027 - 0.2205 0.0185 0.0009 +0.5589 +0.5589 0.0028 0.0181 0.0022 - 0.0028 0.0067 0.0004 0.0056 0.0056
			Full cubeful rollout with var.redn.
			364 games, Mersenne Twister dice gen. with seed 897034043 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	13/9 13/8	+0.5574 ( -0.0201)
			0.7787 0.2365 0.0006 - 0.2213 0.0290 0.0017 +0.5574 +0.5574 0.0025 0.0169 0.0005 - 0.0025 0.0072 0.0010 0.0050 0.0050
			Full cubeful rollout with var.redn.
			363 games, Mersenne Twister dice gen. with seed 897034043 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	R	8/3 6/2	+0.5339 ( -0.0437)
			0.7669 0.2245 0.0003 - 0.2331 0.0241 0.0011 +0.5339 +0.5339 0.0029 0.0195 0.0003 - 0.0029 0.0079 0.0009 0.0057 0.0057
			Full cubeful rollout with var.redn.
			308 games, Mersenne Twister dice gen. with seed 897034043 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]

Annotation

1. Cubeful 2-ply 8/4 7/2 Eq.: +0.7194

0.8597 0.1476 0.0006 - 0.1403 0.0091 0.0000

2-ply cubeful prune [world class]

2. Cubeful 2-ply 7/2 6/2 Eq.: +0.6650 ( -0.0544)

0.8325 0.1789 0.0006 - 0.1675 0.0122 0.0000

2-ply cubeful prune [world class]

3. Cubeful 2-ply 8/3 6/2 Eq.: +0.6538 ( -0.0656)

0.8269 0.1061 0.0004 - 0.1731 0.0125 0.0000

2-ply cubeful prune [world class]

4. Cubeful 2-ply 8/3 7/3 Eq.: +0.6317 ( -0.0877)

0.8158 0.1002 0.0005 - 0.1842 0.0137 0.0000

2-ply cubeful prune [world class]

5. Cubeful 2-ply 8/4 6/1 Eq.: +0.6302 ( -0.0891)

0.8151 0.0959 0.0004 - 0.1849 0.0143 0.0000

2-ply cubeful prune [world class]

6. Cubeful 2-ply 13/9 13/8 Eq.: +0.5977 ( -0.1217)

0.7988 0.1144 0.0004 - 0.2012 0.0133 0.0001

2-ply cubeful prune [world class]

Messages In This Thread

• Payment due?
  Daniel Murphy -- Monday, 2 August 2010, at 2:23 a.m.
  • Payment due?
    Matt Cohn-Geier -- Monday, 2 August 2010, at 2:27 a.m.
  • Payment due?
    Timothy Chow -- Monday, 2 August 2010, at 2:55 a.m.
  • Payment due?
    Chuck Bower -- Monday, 2 August 2010, at 5:26 p.m.
  • Payment due? -- Rollout
    Daniel Murphy -- Monday, 2 August 2010, at 9:25 p.m.
    • Payment due? -- Rollout
      Paul Weaver -- Monday, 2 August 2010, at 9:57 p.m.
      • Rollout: 1ply/3ply, but good enough for me
        Klaus Evers -- Monday, 2 August 2010, at 10:20 p.m.
        • Rollout: 1ply/3ply, but good enough for me
          Timothy Chow -- Monday, 2 August 2010, at 11:12 p.m.
          • Fill in Board, then Pick and Pass
            Paul Weaver -- Tuesday, 3 August 2010, at 12:41 a.m.
            • We agree *NM*
              neilkaz -- Tuesday, 3 August 2010, at 12:43 a.m.
            • Fill in Board, then Pick and Pass
              Matt Cohn-Geier -- Tuesday, 3 August 2010, at 1:23 a.m.
    • Payment due? -- Rollout
      neilkaz -- Monday, 2 August 2010, at 11:26 p.m.
      • Payment due? -- Rollout #2
        Stick -- Tuesday, 3 August 2010, at 3:58 a.m.