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Next to Nothing Play or is XG Rollout Right?

Posted By: Neil Robins
Date: Wednesday, 8 September 2010, at 9:04 p.m.

I'll just post the rollouts I have straight off on this because I doubt many people would feel strongly about the play choice.I probably wouldn't have looked at this if the XG analysis settings I was using hadn't sent it to a second pass rollout. The problem is I'm pretty unable to understand how XG is finding such a difference in equity here and how it comes up in a longish race with the candidate play winning the least often being clearly best whilst the one I played, which wins the most, is worst. The GNU rollout is much TCTC to call between any of the plays, as I would expect, and orders them the same way it orders winning chances. Next problem is that I'm wondering why XG and GNU come up with equity values in general that don't look remotely comparable when both rollouts are using the RK MET. I'd appreciate any thoughts on any of this.

		White is XG Roller score: 5 pip: 112 7 point match pip: 119 score: 3 Blue is Neil
XGID=---AABC-D---cD-aaaacbba---:0:0:1:32:3:5:0:7:10
Blue to play 32

1.	Rollout1	13/11 13/10	eq: -0.197
	Player: Opponent: 38.74% (G:0.01% B:0.00%) 61.26% (G:0.03% B:0.00%) Conf: ± 0.004 (-0.201...-0.193) Duration: 43 minutes 40 seconds
2.	Rollout1	13/10 8/6	eq: -0.207 (-0.010)
	Player: Opponent: 38.81% (G:0.01% B:0.00%) 61.19% (G:0.02% B:0.00%) Conf: ± 0.004 (-0.211...-0.203) Duration: 1 hour 02 minutes
3.	Rollout1	13/11 8/5	eq: -0.211 (-0.014)
	Player: Opponent: 38.81% (G:0.01% B:0.00%) 61.19% (G:0.04% B:0.00%) Conf: ± 0.004 (-0.215...-0.207) Duration: 1 hour 03 minutes
4.	Rollout1	8/6 8/5	eq: -0.212 (-0.014)
	Player: Opponent: 38.83% (G:0.01% B:0.00%) 61.17% (G:0.03% B:0.00%) Conf: ± 0.004 (-0.216...-0.208) Duration: 50 minutes 08 seconds
1 15552 Games rolled with Variance Reduction. Dice Seed: 31247 First 2 moves and cube decisions: 4 ply Remaining moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

The score (after 5 games) is: XG_Roller 5, Neil 3 (match to 7 points)

Move number 12: Neil to play 32

#		Ply	Move	Equity
•	1	R	8/6 8/5	-0.2741
			0.3905 0.0002 0.0000 - 0.6095 0.0003 0.0000 -0.2193 -0.2741 0.0004 0.0001 0.0000 - 0.0004 0.0001 0.0000 0.0009 0.0029
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 894974196 and quasi-random dice
			Stop when best play is enough JSDs ahead: limit 3.1 (min. 1296 games)
			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	13/11 13/10	-0.2751 ( -0.0010)
			0.3899 0.0001 0.0000 - 0.6101 0.0003 0.0000 -0.2205 -0.2751 0.0004 0.0000 0.0000 - 0.0004 0.0003 0.0002 0.0009 0.0029
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 894974196 and quasi-random dice
			Stop when best play is enough JSDs ahead: limit 3.1 (min. 1296 games)
			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	13/11 8/5	-0.2757 ( -0.0016)
			0.3899 0.0002 0.0000 - 0.6101 0.0004 0.0000 -0.2208 -0.2757 0.0005 0.0000 0.0000 - 0.0005 0.0001 0.0001 0.0009 0.0030
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 894974196 and quasi-random dice
			Stop when best play is enough JSDs ahead: limit 3.1 (min. 1296 games)
			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	13/10 8/6	-0.2766 ( -0.0026)
			0.3891 0.0001 0.0000 - 0.6109 0.0008 0.0000 -0.2223 -0.2766 0.0004 0.0000 0.0000 - 0.0004 0.0005 0.0001 0.0009 0.0029
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 894974196 and quasi-random dice
			Stop when best play is enough JSDs ahead: limit 3.1 (min. 1296 games)
			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]

Messages In This Thread

• Next to Nothing Play or is XG Rollout Right?
  Neil Robins -- Wednesday, 8 September 2010, at 9:04 p.m.
  • Next to Nothing Play or is XG Rollout Right?
    Stick -- Wednesday, 8 September 2010, at 9:29 p.m.
    • Next to Nothing Play or is XG Rollout Right?
      Timothy Chow -- Thursday, 9 September 2010, at 2:06 a.m.
      • Next to Nothing Play or is XG Rollout Right?
        Chuck Bower -- Saturday, 11 September 2010, at 3:22 p.m.