BGonline.org Forums

Variants (cusp-flanking)

Posted By: Nack Ballard
Date: Sunday, 25 October 2015, at 1:57 a.m.

In Response To: PrimeVsPrime non commitment (svilo)

 White is Player 2 score: 1 pip: 131 7 point match pip: 154 score: 0 Blue is Player 1
XGID=-aaB-BCBB--------bdebB-A-A:0:0:1:31:0:1:0:7:10
Blue to play 31

1.XG Roller++Bar/22 23/22eq: +0.385
 Player:Opponent: 59.04% (G:16.55% B:0.64%)40.96% (G:11.69% B:0.42%)
2.XG Roller++Bar/21eq: +0.293 (-0.092)
 Player:Opponent: 57.00% (G:14.98% B:0.61%)43.00% (G:12.60% B:0.43%)

Above is the XGR++ evaluation of Svilo's position.

The only way I found to make the choice close (without being more radical) is to extend White's prime.

In Variant 1 below, a spare from each of White's points is moved back to make her 9pt. That's still not quite enough to overturn the robust @ (anchor, bar/22 23/22).

Variant 2 is the same as Variant 1, except for a minor spare adjustment. That's enough to (barely) reverse the order of the best and second best play.

Nack

 White is Player 2 score: 1 pip: 136 7 point match pip: 154 score: 0 Blue is Player 1
XGID=-aaB-BCBB-------bbcdbB-A-A:0:0:1:31:0:1:0:7:10

Variant 1

1.Rollout1Bar/22 23/22eq: -0.326
 Player:Opponent: 41.83% (G:11.89% B:0.65%)58.17% (G:17.39% B:0.69%) Conf.: กำ 0.006 (-0.332...-0.320) - [100.0%]Duration: 5 hours 03 minutes
2.Rollout1Bar/21eq: -0.340 (-0.014)
 Player:Opponent: 41.54% (G:11.01% B:0.52%)58.46% (G:16.64% B:0.62%) Conf.: กำ 0.005 (-0.345...-0.334) - [0.0%]Duration: 5 hours 17 minutes

1 10368 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller

 White is Player 2 score: 1 pip: 138 7 point match pip: 154 score: 0 Blue is Player 1
XGID=-aaB-BCBB-------bcccbB-A-A:0:0:1:31:0:1:0:7:10

Variant 2

1.Rollout1Bar/21eq: -0.398
 Player:Opponent: 40.03% (G:10.58% B:0.52%)59.97% (G:16.58% B:0.61%) Conf.: กำ 0.005 (-0.403...-0.393) - [95.8%]Duration: 5 hours 14 minutes
2.Rollout1Bar/22 23/22eq: -0.405 (-0.007)
 Player:Opponent: 39.73% (G:11.23% B:0.58%)60.27% (G:17.67% B:0.64%) Conf.: กำ 0.006 (-0.411...-0.399) - [4.2%]Duration: 4 hours 53 minutes

1 10368 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller

Post Response

Subject:
Message: