Help with contact situations - Cross over with a 1?

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Help with contact situations - Cross over with a 1?

Posted By: Taper_Mike
Date: Tuesday, 26 July 2011, at 10:51 p.m.

In Response To: Help with contact situations - Cross over with a 1? (Daniel Murphy)

Your points are all valid, notwithstanding the very close rollout results.
I have learned from my experience working with one-sided bear-off programs is how inefficient it is to race with checkers on the bar point. Here's one of my "take aways:"
One interesting thing I noticed while preparing the spreadsheet [of ideal racing positions is] how undesirable it is to place any checkers on the bar point in a race. It came as a surprise to me that there is only one ideal position for 15 checkers that puts a checker there. It occurs at pip count 80, and even it has only a single checker on the bar point. For *any* other pip count, the ideal racing postion leaves the bar point bare. That's a bit of information that is easy to remember, and easy to apply over the board.
Source: http://www.bgonline.org/forums/webbbs_config.pl?noframes;read=99362
Mike

White is Player 2

score: 0
pip: 101

Unlimited Game
Jacoby

pip: 91
score: 0

Blue is Player 1

XGID=-AAABBDA--A-bB-ab--cbda---:1:-1:1:51:0:0:1:0:10
Blue to play 51

1. Rollout¹ 10/5 6/5 eq: +0.369
Player:
Opponent: 72.77% (G:0.18% B:0.00%)
27.23% (G:0.12% B:0.01%) Conf.: ą 0.002 (+0.367...+0.371) - [91.3%]
Duration: 11 minutes 44 seconds
2. Rollout¹ 10/4 eq: +0.367 (-0.002)
Player:
Opponent: 72.70% (G:0.13% B:0.00%)
27.30% (G:0.09% B:0.01%) Conf.: ą 0.002 (+0.365...+0.369) - [8.7%]
Duration: 9 minutes 55 seconds

¹ 5184 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.00