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Advanced Backgammon part 22C

Posted By: Matt Cohn-Geier
Date: Wednesday, 25 March 2009, at 10:49 p.m.

In Response To: Advanced Backgammon part 22C (Matt Cohn-Geier)

Position 217:

Splitting off the anchor is very very wrong, and probably wrong even at DMP. It is slightly better to slot the bar and try to make a full prime, paying off to the potential shot/hit/16 rehit joker sequence.

Move number 5: Blue to play 12

White	64
Blue	123
Position ID: dzNnAAC2bRgABw Match ID: UYkIAAAAAAAA

• Blue moves 10/7

#		Ply	Move	Equity
•	1	R	10/7	-0.2832
			0.3317 0.0397 0.0010 - 0.6683 0.0521 0.0001 -0.3480 -0.2832 0.0003 0.0003 0.0000 - 0.0003 0.0002 0.0000 0.0007 0.0008
			Full cubeful rollout with var.redn.
			18597 games, Mersenne Twister dice gen. with seed 812421792 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	10/9 10/8	-0.2861 ( -0.0029)
			0.3252 0.0358 0.0009 - 0.6748 0.0525 0.0001 -0.3655 -0.2861 0.0003 0.0002 0.0000 - 0.0003 0.0002 0.0000 0.0006 0.0008
			Full cubeful rollout with var.redn.
			18597 games, Mersenne Twister dice gen. with seed 812421792 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Position 218:

As is often the case in mutual holding games, Blue is running out of time, but running off the anchor is very wrong.

Move number 5: Blue to play 35

White	101
Blue	107
Position ID: bW4HAAbb3IABBg Match ID: UYkVAAAAAAAA

• Blue moves 13/5

#		Ply	Move	Equity
•	1	R	13/5	+0.0823
			0.4589 0.0695 0.0023 - 0.5411 0.0735 0.0020 -0.0860 +0.0823 0.0023 0.0035 0.0006 - 0.0023 0.0034 0.0004 0.0055 0.0084
			Full cubeful rollout with var.redn.
			273 games, Mersenne Twister dice gen. with seed 811694589 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	21/13	-0.0517 ( -0.1340)
			0.4210 0.0801 0.0036 - 0.5790 0.1314 0.0005 -0.2063 -0.0517 0.0027 0.0042 0.0006 - 0.0027 0.0037 0.0004 0.0066 0.0095
			Full cubeful rollout with var.redn.
			273 games, Mersenne Twister dice gen. with seed 811694589 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Position 219:

Ripping is clear here and probably slightly better at DMP. Blue is probably a bigger favorite to get hit later on but by the time he gets hit he will likely have several checkers off. And, of course, Gs pay double.

Move number 5: Blue to play 23

White	112
Blue	48
Position ID: ZvcBBAPrzQMAAA Match ID: QQkNAAAAAAAA

• Blue moves 3/off 2/off

#		Ply	Move	Equity
•	1	R	3/off 2/off	+1.1011
			0.9823 0.1443 0.0008 - 0.0177 0.0000 0.0000 +1.1098 +1.1011 0.0017 0.0038 0.0005 - 0.0017 0.0000 0.0000 0.0039 0.0047
			Full cubeful rollout with var.redn.
			143 games, Mersenne Twister dice gen. with seed 811694589 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	4/2 3/off	+1.0704 ( -0.0307)
			0.9806 0.1206 0.0007 - 0.0194 0.0000 0.0000 +1.0825 +1.0704 0.0015 0.0033 0.0005 - 0.0015 0.0000 0.0000 0.0042 0.0057
			Full cubeful rollout with var.redn.
			143 games, Mersenne Twister dice gen. with seed 811694589 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Position 220:

Making the ace point is best here. Blue's game plan isn't to prime White's back checkers, it's just to keep him on the bar until Blue is bearing off.

Move number 6: Blue to play 46

White	157
Blue	131
Position ID: yHPGARjZtsABSA Match ID: QQkaAAAAAAAA

• Blue moves bar/21* 7/1

#		Ply	Move	Equity
•	1	R	bar/21* 7/1	+0.5590
			0.6887 0.3578 0.0164 - 0.3113 0.0450 0.0016 +0.7049 +0.5590 0.0014 0.0015 0.0006 - 0.0014 0.0008 0.0001 0.0034 0.0050
			Full cubeful rollout with var.redn.
			2953 games, Mersenne Twister dice gen. with seed 812286745 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	bar/21* 13/7	+0.5202 ( -0.0387)
			0.6834 0.3302 0.0200 - 0.3166 0.0565 0.0022 +0.6582 +0.5202 0.0023 0.0028 0.0022 - 0.0023 0.0011 0.0003 0.0074 0.0089
			Full cubeful rollout with var.redn.
			1581 games, Mersenne Twister dice gen. with seed 812286745 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Messages In This Thread

• Advanced Backgammon part 22C
  Matt Cohn-Geier -- Thursday, 19 March 2009, at 4:12 a.m.
  • Advanced Backgammon part 22C
    Christian Munk-Christensen -- Thursday, 19 March 2009, at 12:47 p.m.
  • Advanced Backgammon part 22C
    Chuck Bower -- Thursday, 19 March 2009, at 7:05 p.m.
  • Robertie's picks
    Matt Cohn-Geier -- Friday, 20 March 2009, at 2:41 a.m.
  • Advanced Backgammon part 22C
    neilkaz -- Friday, 20 March 2009, at 2:52 p.m.
  • Advanced Backgammon part 22C
    Keene -- Friday, 20 March 2009, at 6:52 p.m.
  • Advanced Backgammon part 22C
    Matt Cohn-Geier -- Wednesday, 25 March 2009, at 10:49 p.m.
    • Advanced Backgammon part 22C
      Chuck Bower -- Thursday, 26 March 2009, at 1:59 p.m.
      • Advanced Backgammon part 22C
        Matt Cohn-Geier -- Thursday, 26 March 2009, at 4:40 p.m.
      • Advanced Backgammon part 22C
        Matt Cohn-Geier -- Thursday, 26 March 2009, at 4:41 p.m.