Another early blitz cube

[Timothy Chow]

XGID=aCaBB-B-----dD-a-c-e----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 X |
| X O | | O X |
| X O | | O |
| X | | O |
| | | O |
| |BAR| |
| | O | |
| O | | |
| O | | X |
| O | | X X X X |
| O | | X X X O X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 129 O: 164 X-O: 0-0
Cube: 1
X on roll, cube action

---
Tim Chow

[peps...@gmail.com]

I would hold this one because I don't think our threats are so overwhelming.
Some sequences do lose market, but the market loss is unlikely to be large.
Also, our wasted acepoint checker is a huge liability.
I wonder whether Tim is going to unsurprise us by variantizing the wasted acepoint checker
to a useful slot and proclaiming a D/P.
A great sequence would be 43, dance but this is either still a take or a very close pass.
So don't double now.
ND/T.

Paul

[Stick Rice]

Move the checker from the ace point to the midpoint and it's a known position that certain people have memorized. The question then simply becomes is it better for that checker to be on the ace point (12 pips better in the race, whoopie!) or back on the midpoint. Clearly it's better on the midpoint. The question then, how much better? The answer...a freaking ton. So the position goes from a pass to a take. The double is still trivial as all fanning sequences by the opponent are massive regardless of what we roll.

Stick

[ah....Clem]

Position, race, threats. That usually implies D/P, but X is still on O's
ace point and has three checkers on his own ace point. That seems like
enough to push it to D/T.

--
Ah....Clem
The future is fun, the future is fair.

[peps...@gmail.com]

Good and correct analysis. The opponent's dances are dire/great [depending on which side]
and I should have taken more account of this.

Paul

[Timothy Chow]

As Paul and Stick mentioned, one of the main questions here is, just
how bad is the checker on the ace point? There are many variants one
could consider; I'm posting just one that I found interesting.

Analyzed in Rollout
No double
Player Winning Chances: 64.16% (G:36.40% B:0.91%)
Opponent Winning Chances: 35.84% (G:7.88% B:0.34%)
Double/Take
Player Winning Chances: 64.42% (G:36.92% B:0.82%)
Opponent Winning Chances: 35.58% (G:8.00% B:0.34%)

Cubeful Equities:
No double: +0.731 (-0.139)
Double/Take: +0.870
Double/Pass: +1.000 (+0.130)

Best Cube action: Double / Take

Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.014 (+0.717..+0.745)
Confidence Double: ± 0.023 (+0.847..+0.893)

eXtreme Gammon Version: 2.19.211.pre-release

-------
Variant
-------

XGID=aBaBB-B-----dD-a-c-e--A-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 X X |
| X O | | O X |
| X O | | O |
| X | | O |
| | | O |
| |BAR| |
| | O | |
| O | | |
| O | | |

| O | | X X X X |
| O | | X X X O X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+

Pip count X: 150 O: 164 X-O: 0-0

Cube: 1
X on roll, cube action

Analyzed in Rollout
No double
Player Winning Chances: 66.05% (G:35.91% B:1.31%)
Opponent Winning Chances: 33.95% (G:7.36% B:0.34%)
Double/Take
Player Winning Chances: 66.28% (G:36.77% B:1.32%)
Opponent Winning Chances: 33.72% (G:7.58% B:0.35%)

Cubeful Equities:
No double: +0.802 (-0.179)
Double/Take: +0.982
Double/Pass: +1.000 (+0.018)

Best Cube action: Double / Take

Rollout:
2592 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.009 (+0.793..+0.812)
Confidence Double: ± 0.014 (+0.968..+0.996)

eXtreme Gammon Version: 2.19.211.pre-release

---
Tim Chow