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Rollout

Posted By: Timothy Chow
Date: Thursday, 24 December 2009, at 3:39 p.m.

In Response To: Money game: Blue to play 62 (Timothy Chow)

OTB, I ran with 24/16. Like Neil, I didn't really think there was any plausible alternative except 13/5, which I didn't like. So I was surprised that GNU 4-ply thought my play was a 0.046 error, with 13/11 13/7 coming out on top. I know that having a stronger board allows one to play boldly, but this play didn't even cross my radar screen. Nack once again demonstrates his mastery of the openings by selecting 13/11 13/7. I still don't fully understand his explanation; perhaps one problem is that I don't have a good enough feeling for cube efficiency.

The equity difference between 13/11 13/7 and 24/16 in the rollout is less than GNU 4-ply's prediction, but 13/11 13/7 still comes out on top. After reading Nack's reply, I rolled out the position with White owning the cube (see below). As Nack suspected, the equity difference between the top two plays seems to shrink still further, though the rollouts are too short to say for sure.

gnubg	142
tchow	142
Position ID: 4PMxAyBsTvADIA Match ID: cAkLANAAGAAA

#		Ply	Move	Equity
•	1	R	13/11 13/7	+0.208
			0.537 0.185 0.006 - 0.463 0.106 0.005 +0.155 +0.208 0.001 0.001 0.000 - 0.001 0.001 0.000 0.003 0.007
			Full cubeful rollout with var.redn.
			2592 games, Mersenne Twister dice gen. with seed 840833160 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]
	2	R	24/16	+0.183 ( -0.024)
			0.546 0.118 0.004 - 0.454 0.091 0.003 +0.120 +0.183 0.001 0.001 0.000 - 0.001 0.001 0.000 0.002 0.006
			Full cubeful rollout with var.redn.
			2592 games, Mersenne Twister dice gen. with seed 840833160 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]
	3	R	24/18 13/11	+0.175 ( -0.033)
			0.545 0.125 0.005 - 0.455 0.098 0.003 +0.118 +0.175 0.001 0.001 0.000 - 0.001 0.001 0.000 0.002 0.006
			Full cubeful rollout with var.redn.
			2592 games, Mersenne Twister dice gen. with seed 840833160 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]

gnubg	142
tchow	142
Position ID: 4PMxAyBsTvADIA Match ID: QQkLAAAAAAAA

#		Ply	Move	Equity
•	1	R	13/11 13/7	-0.021
			0.543 0.191 0.006 - 0.457 0.107 0.005 +0.171 -0.021 0.002 0.002 0.001 - 0.002 0.001 0.000 0.004 0.007
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 839828076 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]
	2	R	24/16	-0.034 ( -0.013)
			0.553 0.117 0.004 - 0.447 0.089 0.003 +0.135 -0.034 0.001 0.002 0.000 - 0.001 0.002 0.001 0.004 0.006
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 839828076 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]
	3	R	24/18 13/11	-0.050 ( -0.029)
			0.551 0.127 0.005 - 0.449 0.101 0.004 +0.128 -0.050 0.002 0.002 0.000 - 0.002 0.001 0.000 0.004 0.006
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 839828076 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]
	4	R	13/5	-0.098 ( -0.077)
			0.523 0.169 0.004 - 0.477 0.104 0.005 +0.111 -0.098 0.002 0.002 0.001 - 0.002 0.002 0.001 0.004 0.007
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 839828076 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]

Messages In This Thread

• Money game: Blue to play 62
  Timothy Chow -- Friday, 18 December 2009, at 12:54 a.m.
  • Money game: Blue to play 62
    neilkaz -- Friday, 18 December 2009, at 3:11 a.m.
  • Money game: Blue to play 62
    David -- Friday, 18 December 2009, at 3:34 a.m.
  • Money game: Blue to play 62
    Seth -- Friday, 18 December 2009, at 3:56 a.m.
  • Money game: Blue to play 62
    Joe Russell -- Friday, 18 December 2009, at 4:27 a.m.
  • Money game: Blue to play 62
    lenny -- Friday, 18 December 2009, at 7:45 a.m.
  • 53P-52D-65R-65R-42P-52D-62
    Nack Ballard -- Friday, 18 December 2009, at 7:45 p.m.
    • 53P-52D-65R-65R-42P-52D-62
      John O'Hagan -- Friday, 18 December 2009, at 11:31 p.m.
      • 53P-52D-65R-65R-42P-52D-62
        Nack Ballard -- Saturday, 19 December 2009, at 4:09 a.m.
  • Money game: Blue to play 62
    Matt Cohn-Geier -- Friday, 18 December 2009, at 11:39 p.m.
  • Rollout
    Timothy Chow -- Thursday, 24 December 2009, at 3:39 p.m.
    • Rollout
      Rich Munitz -- Thursday, 24 December 2009, at 4:07 p.m.