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birol's "simple" position revisited

Posted By: Stick
Date: Monday, 6 September 2010, at 9:11 p.m.

In Response To: birol's "simple" position revisited (Timothy Chow)

Recently birol posted a "simple" problem. Here are some rollouts that demonstrate the sensitivity of the checker play to the score. In particular, I'm surprised at the difference between money and 7a7a. Does XG confirm these results?

First off, I think it's a sham to roll this out for money or -7 -7 with the cube centered. It skews the results and everyone down to Chuck Bower knows it's a double. What you will have to do to figure out if it's a bot problem or is look at all the plays/sequences and see if either bot thinks it's TG after double + fan (they don't) and then move on to see how each bot handles the entering numbers that fail to hit and see if the bot is correctly taking or passing. The game would have to be played out if I was playing because the cube would be on my opponent's side so I think we should put it there to begin with.

I've included both money rollouts below, both with the cube centered and turned as it should be. Same for -7 -7.

	is Player 2 score: 0 pip: 79 Money session pip: 75 score: 0 is Player 1
XGID=-CB-aDC---C-------bbbd-bb-:0:0:1:64:0:0:0:0:10
to play 64

1.	Rollout1	10/4* 5/1	eq: +0.316
	Player: Opponent: 60.35% (G:0.76% B:0.01%) 39.65% (G:2.59% B:0.02%) Conf: ± 0.003 (+0.313...+0.319) Duration: 54.9 seconds
2.	Rollout1	10/4* 6/2	eq: +0.299 (-0.017)
	Player: Opponent: 59.75% (G:0.76% B:0.01%) 40.25% (G:2.60% B:0.02%) Conf: ± 0.003 (+0.296...+0.302) Duration: 55.2 seconds
3.	Rollout1	10/6 10/4*	eq: +0.278 (-0.038)
	Player: Opponent: 62.43% (G:0.91% B:0.01%) 37.57% (G:7.14% B:0.17%) Conf: ± 0.002 (+0.276...+0.280) Duration: 41.7 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 79870500 Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21

---

	is Player 2 score: 0 pip: 79 Money session pip: 75 score: 0 is Player 1
XGID=-CB-aDC---C-------bbbd-bb-:1:-1:1:64:0:0:0:0:10
to play 64

1.	Rollout1	10/6 10/4*	eq: +0.122
	Player: Opponent: 62.18% (G:1.54% B:0.01%) 37.82% (G:7.18% B:0.17%) Conf: ± 0.003 (+0.119...+0.125) Duration: 2 minutes 54 seconds
2.	Rollout1	10/4* 5/1	eq: +0.096 (-0.026)
	Player: Opponent: 60.06% (G:1.20% B:0.01%) 39.94% (G:2.51% B:0.02%) Conf: ± 0.002 (+0.094...+0.098) Duration: 2 minutes 33 seconds
3.	Rollout1	10/4* 6/2	eq: +0.083 (-0.039)
	Player: Opponent: 59.43% (G:1.16% B:0.01%) 40.57% (G:2.55% B:0.02%) Conf: ± 0.002 (+0.081...+0.085) Duration: 2 minutes 15 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 79870500 Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21

---

	is Player 2 score: 0 pip: 79 7 point match pip: 75 score: 0 is Player 1
XGID=-CB-aDC---C-------bbbd-bb-:0:0:1:64:0:0:0:7:10
to play 64

1.	Rollout1	10/4* 5/1	eq: +0.316
	Player: Opponent: 60.35% (G:0.75% B:0.01%) 39.65% (G:2.59% B:0.03%) Conf: ± 0.003 (+0.313...+0.319) Duration: 58.8 seconds
2.	Rollout1	10/4* 6/2	eq: +0.300 (-0.016)
	Player: Opponent: 59.76% (G:0.77% B:0.01%) 40.24% (G:2.61% B:0.02%) Conf: ± 0.003 (+0.297...+0.303) Duration: 57.4 seconds
3.	Rollout1	10/6 10/4*	eq: +0.275 (-0.041)
	Player: Opponent: 62.45% (G:0.90% B:0.01%) 37.55% (G:7.17% B:0.17%) Conf: ± 0.002 (+0.273...+0.277) Duration: 47.4 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 79870500 Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

---

	is Player 2 score: 0 pip: 79 7 point match pip: 75 score: 0 is Player 1
XGID=-CB-aDC---C-------bbbd-bb-:1:-1:1:64:0:0:0:7:10
to play 64

1.	Rollout1	10/6 10/4*	eq: +0.118
	Player: Opponent: 62.21% (G:1.56% B:0.01%) 37.79% (G:7.23% B:0.19%) Conf: ± 0.002 (+0.116...+0.120) Duration: 2 minutes 58 seconds
2.	Rollout1	10/4* 5/1	eq: +0.095 (-0.022)
	Player: Opponent: 60.07% (G:1.20% B:0.01%) 39.93% (G:2.52% B:0.03%) Conf: ± 0.002 (+0.093...+0.097) Duration: 2 minutes 38 seconds
3.	Rollout1	10/4* 6/2	eq: +0.082 (-0.036)
	Player: Opponent: 59.43% (G:1.15% B:0.01%) 40.57% (G:2.55% B:0.03%) Conf: ± 0.002 (+0.080...+0.084) Duration: 2 minutes 20 seconds
1 5184 Games rolled with Variance Reduction. Dice Seed: 79870500 Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

Messages In This Thread

• birol's "simple" position revisited
  Timothy Chow -- Monday, 6 September 2010, at 8:21 p.m.
  • birol's "simple" position revisited
    Bob Koca -- Monday, 6 September 2010, at 9:00 p.m.
  • birol's "simple" position revisited
    Stick -- Monday, 6 September 2010, at 9:11 p.m.