From
Timothy Chow@21:1/5 to
All on Fri Dec 29 08:52:05 2023
XGID=-a--BbDBB---bE---c-dc-----:0:0:1:00:0:0:0:0:10
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O |
| X O | | O O |
| X O | | O O |
| X | | O |
| X | | |
| |BAR| |
| | | |
| | | X |
| | | X |
| O X X | | X O X |
| O X X | | X O X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 127 O: 153 X-O: 0-0
Cube: 1
X on roll, cube action
I judged this position to be a pass, and was pretty confused that XG
thought it was an easy take. A "normal" 5pt holding game in which X
has filled in his bar point (in addition to the 8pt), and in which X
has this much of a lead in a pip count, is generally a pass. So is
the difference that O has an extra checker back? That does usually
increase O's winning chances, but at the cost of more gammon losses,
so I didn't think that was the main explanation.
Finally the penny dropped: I realized that I was overlooking that
X still has five checkers on his midpoint. That makes it harder for
X to clear his midpoint safely (e.g., big doublets don't clear it
immediately), and gives O enough vig for an easy take.
Analyzed in Rollout
No double
Player Winning Chances: 72.93% (G:9.83% B:0.30%)
Opponent Winning Chances: 27.07% (G:4.15% B:0.10%)
Double/Take
Player Winning Chances: 72.94% (G:9.76% B:0.30%)
Opponent Winning Chances: 27.06% (G:4.16% B:0.10%)
Cubeful Equities:
No double: +0.868
Double/Take: +0.861 (-0.007)
Double/Pass: +1.000 (+0.132)
Best Cube action: No double / Take
Percentage of wrong pass needed to make the double decision right: 4.9%
Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.011 (+0.856..+0.879)
Confidence Double: ± 0.013 (+0.848..+0.874)
eXtreme Gammon Version: 2.19.211.pre-release
---------
Variant 1
---------
XGID=-a--BbDBC---bD---c-dc-----:0:0:1:00:0:0:0:0:10
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O |
| X O | | O O |
| X O | | O O |
| X | | O |
| | | |
| |BAR| |
| | | |
| | | X |
| X | | X |
| O X X | | X O X |
| O X X | | X O X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 122 O: 153 X-O: 0-0
Cube: 1
X on roll, cube action
Analyzed in Rollout
No double
Player Winning Chances: 76.17% (G:10.50% B:0.20%)
Opponent Winning Chances: 23.83% (G:2.96% B:0.07%)
Double/Take
Player Winning Chances: 76.48% (G:10.69% B:0.23%)
Opponent Winning Chances: 23.52% (G:3.14% B:0.08%)
Cubeful Equities:
No double: +0.986 (-0.014)
Double/Take: +1.066 (+0.066)
Double/Pass: +1.000
Best Cube action: Double / Pass
Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.008 (+0.978..+0.995)
Confidence Double: ± 0.013 (+1.053..+1.079)
eXtreme Gammon Version: 2.19.211.pre-release
---------
Variant 2
---------
XGID=-a--BbDBC---bD---c-cb-b---:0:0:1:00:0:0:0:0:10
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O O |
| X O | | O O O |
| X O | | O |
| X | | |
| | | |
| |BAR| |
| | | |
| | | X |
| X | | X |
| O X X | | X O X |
| O X X | | X O X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 122 O: 148 X-O: 0-0
Cube: 1
X on roll, cube action
Analyzed in Rollout
No double
Player Winning Chances: 75.58% (G:8.87% B:0.14%)
Opponent Winning Chances: 24.42% (G:3.01% B:0.06%)
Double/Take
Player Winning Chances: 75.75% (G:8.95% B:0.14%)
Opponent Winning Chances: 24.25% (G:3.21% B:0.06%)
Cubeful Equities:
No double: +0.961 (-0.039)
Double/Take: +1.007 (+0.007)
Double/Pass: +1.000
Best Cube action: Double / Pass
Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.009 (+0.952..+0.970)
Confidence Double: ± 0.013 (+0.994..+1.020)
eXtreme Gammon Version: 2.19.211.pre-release
---
Tim Chow
--- SoupGate-Win32 v1.05
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