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Hit, Cover or Point? — 3-ply XG2 Rollout

Posted By: Taper_Mike
Date: Sunday, 9 September 2012, at 12:30 p.m.

In Response To: Hit, Cover or Point? (Taper_Mike)

–

		White is Player 2 score: 0 pip: 145 Unlimited Game Jacoby Beaver pip: 147 score: 0 Blue is Player 1
XGID=--aB-aDAC---dB----bdCc----:0:0:1:42:0:0:3:0:10
Blue to play 42

1.	Rollout1	7/5* 6/2*	eq: +0.1901
	Player: Opponent: 53.23% (G:18.69% B:0.52%) 46.77% (G:11.69% B:0.42%) Conf.: ±0.0076 (+0.1825...+0.1976) - [100.0%] Duration: 1 hour 10 minutes
2.	Rollout1	8/4 6/4	eq: +0.1517 (-0.0383)
	Player: Opponent: 52.42% (G:16.06% B:0.49%) 47.58% (G:9.50% B:0.34%) Conf.: ±0.0085 (+0.1432...+0.1603) - [0.0%] Duration: 1 hour 08 minutes
3.	Rollout1	20/16 7/5*	eq: +0.1365 (-0.0535)
	Player: Opponent: 52.52% (G:14.89% B:0.50%) 47.48% (G:11.08% B:0.40%) Conf.: ±0.0072 (+0.1294...+0.1437) - [0.0%] Duration: 1 hour 19 minutes
4.	Rollout1	7/5* 5/1	eq: +0.1148 (-0.0753)
	Player: Opponent: 51.66% (G:14.85% B:0.35%) 48.34% (G:9.93% B:0.36%) Conf.: ±0.0068 (+0.1080...+0.1216) - [0.0%] Duration: 1 hour 18 minutes
5.	Rollout1	13/7	eq: +0.0400 (-0.1500)
	Player: Opponent: 50.51% (G:11.65% B:0.36%) 49.49% (G:8.34% B:0.27%) Conf.: ±0.0061 (+0.0339...+0.0462) - [0.0%] Duration: 1 hour 15 minutes
1 5184 Games rolled with Variance Reduction. Dice Seed: 8016842 Moves: 3-ply, cube decisions: XG Roller

Rollout by Taper_Mike 2012-Sep-08 eXtreme Gammon Version: 2.03 21S-53P-41P-32U-32P-52@-31B-65D-42C-65X-42U-42 -tm .xgp [a A38 E54 A75 D150] "<=5

eXtreme Gammon Version: 2.03

21S-53P-41P-32U-32P-52@-31B-65D-42C-65X-42U-42
Unlimited Games

Bot	Seed	Equity	Nacbracs	Rollout by
XG 2.03 3-ply, Cubes: XGR	8016842	+190.1	[a A38 E54 A75 D150] "<=5	Taper_Mike

Hitting loose twice in the inner board in not exactly rare, but it is not common either. Usually, when there is a good alternative, such as A = Attack (8/4 6/4) presents here, there is no need for extreme measures. That’s why it is so interesting that this is clear-cut. Daniel gives a good explantion: “I think the double hit should be better than making the 4 point. 5's and 2's hit back either way, and those probably favor pointing for having made a permanent improvement. But the other 3's (3-6 3-4 3-3 3-1) should favor the double hit in a big way, and the 1-4-6 combinations also, but not as big.” Mike Nactation Note In the nacbracs given here, the best backgammon play, a = attack (7/5* 6/2*), is ranked 2nd in its Nactation family. The top-ranked play in the Attack family, A = Attack (8/4 6/4), makes a new point in the inner board. Under the Hit Convention, it gets top billing, because making a new point in the home board outranks any hit, anywhere on the board. As a contrast with the lower case a that is already part of the nacbracs, I felt that upper case A was a better choice to describe making the 4pt than upper case P (Point). Lower down in the rollout is the play that ranks 3rd in the Attack family, A = Attack (7/5*/1). Its presence reinforces my decision. There are two plays in the P (Point) family. P makes the 4pt, adding a new point, while p covers the bar point by breaking the midpoint. The More Points Convention trumps the 6pt Convention, so making the 4pt gets the capital, even though it is not as close to the 6pt as the bar point is.

Messages In This Thread

• Hit, Cover or Point?
  Taper_Mike -- Saturday, 8 September 2012, at 12:22 p.m.
  • Hit, Cover or Point?
    Casper van der Tak -- Saturday, 8 September 2012, at 1:00 p.m.
    • Hit, Cover or Point?
      Daniel Murphy -- Saturday, 8 September 2012, at 5:31 p.m.
  • Hit, Cover or Point?
    Seth -- Saturday, 8 September 2012, at 2:11 p.m.
  • Hit, Cover or Point? — 3-ply XG2 Rollout
    Taper_Mike -- Sunday, 9 September 2012, at 12:30 p.m.