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the big thread about cube decisions
04-10-2015
, 04:03 AM
04-10-2015
, 06:05 PM
Position 1 is a huge pass on the race (29 pips). White does considerably better here than in a straight race, but not by enough. So I think this is a solid pass.
Position 2 is a big take on the race (13 pips), though it would still be a double based on the race. But again I think White does better than in a straight race, so I think it's OK for Black to hold off for a little stronger position. Doubling isn't bad though, I'd probably double from the outside in my chouette because it means I get to consult
.
Position 2 is a big take on the race (13 pips), though it would still be a double based on the race. But again I think White does better than in a straight race, so I think it's OK for Black to hold off for a little stronger position. Doubling isn't bad though, I'd probably double from the outside in my chouette because it means I get to consult
.
04-11-2015
, 04:15 PM
White - Pips 131
Black - Pips 144
Position 14c. White on roll. Cube action?
Unlimited game, no Jacoby, no beavers
XGID=---B-BB-BAA-eC---cbcbB----:0:0:-1:00:0:0:3:0:10
This is a variation of your second position. I have added 7 pips to both players. The difference is still 13 pips.
What is the cube action now?
Mike
Black - Pips 144
Position 14c. White on roll. Cube action?
Unlimited game, no Jacoby, no beavers
XGID=---B-BB-BAA-eC---cbcbB----:0:0:-1:00:0:0:3:0:10
This is a variation of your second position. I have added 7 pips to both players. The difference is still 13 pips.
What is the cube action now?
Mike
04-13-2015
, 01:11 AM
White - Pips 131
Black - Pips 144
Position 14c. White on roll. Cube action?
Unlimited game, no Jacoby, no beavers
XGID=---B-BB-BAA-eC---cbcbB----:0:0:-1:00:0:0:3:0:10
In a high-anchor holding game, so long as the race deficit is not too big, you can usually take.
Important factors include:
Owning the 7pt can make a big difference. Clearing both the midpoint and the 8pt is much easier when there is no gap on the 7pt. The taker’s shot equity goes down when the gap has been filled, so he needs more race equity if he is going to take.
Even when you have a sufficient racing advantage, it is often incorrect to cube until you get down to 4 or fewer checkers on the midpoint. That's because the opponent will still be taking (in most cases) even after you get down to 4. You have few or no market losers when you still have 5 or more checkers on the midpoint. When you get down to 4, however, rolling a doublet that clears the midpoint is usually a market loser. You must cube before that happens. Note that this Rule of 4 applies almost universally when there is a gap on the 7pt, and less so once that gap has been filled.
By this last rule, Position 14c is not a double. Due to the fact of the made 7pt, the decision is close, but my 5k rollout confirms the choice. Remember, from the original Position 14b, we already know that the opponent is still taking after you get down to 4 on the midpoint.
Mike
5k XG2 Rollout – Unlimited game, no Jacoby, no beavers
Black - Pips 144
Position 14c. White on roll. Cube action?
Unlimited game, no Jacoby, no beavers
XGID=---B-BB-BAA-eC---cbcbB----:0:0:-1:00:0:0:3:0:10
In a high-anchor holding game, so long as the race deficit is not too big, you can usually take.
Important factors include:
- Just how big the deficit is.
- Whether the player offering the cube owns any points besides his 8pt in the outer board.
- How many checkers remain on the midpoint.
Owning the 7pt can make a big difference. Clearing both the midpoint and the 8pt is much easier when there is no gap on the 7pt. The taker’s shot equity goes down when the gap has been filled, so he needs more race equity if he is going to take.
Even when you have a sufficient racing advantage, it is often incorrect to cube until you get down to 4 or fewer checkers on the midpoint. That's because the opponent will still be taking (in most cases) even after you get down to 4. You have few or no market losers when you still have 5 or more checkers on the midpoint. When you get down to 4, however, rolling a doublet that clears the midpoint is usually a market loser. You must cube before that happens. Note that this Rule of 4 applies almost universally when there is a gap on the 7pt, and less so once that gap has been filled.
By this last rule, Position 14c is not a double. Due to the fact of the made 7pt, the decision is close, but my 5k rollout confirms the choice. Remember, from the original Position 14b, we already know that the opponent is still taking after you get down to 4 on the midpoint.
Mike
5k XG2 Rollout – Unlimited game, no Jacoby, no beavers
Code:
XGID=---B-BB-BAA-eC---cbcbB----:0:0:-1:00:0:0:3:0:10
X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game, Jacoby Beaver
Pip count X: 144 O: 131 X-O: 0-0
Cube: 1
O on roll, cube action
Analyzed in Rollout
No double
Player Winning Chances: 72.86% (G:1.96% B:0.05%)
Opponent Winning Chances: 27.14% (G:0.88% B:0.02%)
Double/Take
Player Winning Chances: 73.01% (G:1.90% B:0.06%)
Opponent Winning Chances: 26.99% (G:0.87% B:0.02%)
Cubeless Equities: No Double=+0.4684, Double=+0.9418
Cubeful Equities:
No double: +0.7834
Double/Take: +0.7702 (-0.0132)
Double/Pass: +1.0000 (+0.2166)
Best Cube action: No double / Take
Percentage of wrong pass needed to make the double decision right: 5.4%
Rollout:
5184 Games rolled with Variance Reduction.
Dice Seed: 33602149
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ±0.0046 (+0.7789..+0.7880)
Confidence Double: ±0.0052 (+0.7650..+0.7754)
Double Decision confidence: 100.0%
Take Decision confidence: 100.0%
eXtreme Gammon Version: 2.10
04-15-2015
, 02:37 AM
Position ID: ZrYNADhsG1DgDA Match ID: UqkAAAAAAAAE
04-15-2015
, 04:57 AM
04-15-2015
, 05:00 AM
04-15-2015
, 02:06 PM
04-16-2015
, 01:14 PM
Code:
Cube analysis Rollout cubeless equity +0,705 Cubeful equities: 1. Double, pass +1,000 2. Double, take +1,238 ( +0,238) 3. No double +0,935 ( -0,065) Proper cube action: Redouble, pass
And by giving white some flexibility to maintain his 4-prime it gets a very convincing take:
Code:
Cube analysis Rollout cubeless equity +0,502 Cubeful equities: 1. Double, take +0,767 2. Double, pass +1,000 ( +0,233) 3. No double +0,766 ( -0,001) Proper cube action: Redouble, take
This flexibility can also be realized sufficiently by moving 1w to 2:
Code:
Cube analysis Rollout cubeless equity +0,455 Cubeful equities: 1. No double +0,727 2. Double, pass +1,000 ( +0,273) 3. Double, take +0,677 ( -0,050) Proper cube action: No redouble, take (15,6%)
04-19-2015
, 05:14 AM
Position ID: G1tzAAi4vSMABg Match ID: cAkAAAAAAAAE