cube decision

[stog]

roman hands our cube back..
do we want it though?
take or drop?

[ah_clem]

Our live takepoint is 16% AtS.  I'm certain we are more that 16% to win this one.

But Roman's gammon price is an elevated .75 and there are gammons afoot.  Is that enough to pass?  I say no, but I'm not sure. Losing a single game and getting to 5a3a is no big deal. Losing a gammon and the match is. Twelve in the zone, a man on the bar, and a blot to shoot at is daunting.  But we have a nice board, he has only three points in his homeboard giving us 75% to enter, and a win gets us to 7aC. I'll take this one.

[dahlin]

Spoiler

Im a wellknown chicken - I pass this one, faster than a blitzstorm - I see gammon everywhere in this position, and if I didnt know roman is usually spot on with his cubeactions, I would have thought it to be too good...

From a 'I have no bot' to a herd full of 'I do' - Ill risc any reputation I might have, and say this is a big big

Pass 

[close]

[diane]

Im a wellknown chicken

I shall try to remember that 

Now, I opened this page and it plonked me in Ah_Clems reply - all open to the world..so, I have tried not to let him influence me too much..

I have also tried to work wit the fact that the board image does not match the move posted, in that there is no cube offered, I assume that the rest of the position is correct?

Spoiler

If all that is right, and our board is just like that with a cube on the table, then I take. I'm not saying gammons are impossible, just unlikely. And I consider it more likely that we will come in and get a shot, with a lovely board down there...yup, gimme that!!

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[KDP]

Spoiler

i would let this one go and live to fight another day. a couple of things which lead me to pass are: 1. the race 2. getting a second checker on the bar or worse closed out.  i think his gammon chances are pretty decent and even though we have a strong board its not going to do us much good with 1 or 2 checkers on the bar.

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[dorbel]

Spoiler

An enormous pass. The point here is that roman's big race lead means that he doesn't have to blitz to win and in fact he won't be hitting loose. He can just play quietly and go for a plain win against a 20pt anchor if things go badly and a gammonish win by closeout if things go well, starting with one of the 10 numbers that make the 5pt on our head. Actually this might well be too good for this roll and a cube if we manage to anchor.

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[rif_raf]

black is a take while is a drop

[vegasvic]

Huge PASS only Cube Ho's and checker pushers would think of taking this . 

[dorbel]

On a point of interest, could Clem tell us what this means?

Our live takepoint is 16% AtS.  I'm certain we are more that 16% to win this one.

[ah_clem]

On a point of interest, could Clem tell us what this means?

It means I can't read a chart.  http://www.simborgbackgammonlessons.com/recube-take-points-chart

Our live takepoint is 24%, not 16%.  And with all those gammons the pass now seems clear.  Rollout in progress.

[ah_clem]

rollout

Spoiler

The first step in making a decision like this is evaluating the takepoint.  Somehow, I really screwed up and thought it was 16% when it's more like 24% ( that's non-gammon-adjusted takepoint BTW)  Add in the ~30% gammons and we'd need more like 37% to take and we are nowhere near that good.

As it is, the elevated gammon value for Roman with the cube at 2, and the depressed gammon value with the cube at 4 (8 points is 1 more than he needs so the gammon is worth less than normal) means that this one is too-good.  But perhaps it's a practical double since some donkeys will take this one.

Score matters a lot; reverse the scores and it's a plain vanilla R/T. (see variant)


XGID=---BBBB-B-a-bC---cbcAb--bA:1:-1:-1:00:2:0:0:7:10
X:Player 1   O:Player 2

Score is X:2 O:0 7 pt.(s) match.
+12-11-10--9--8--7-------6--5--4--3--2--1-+
| X           O  O |   | O  X  O        O | +---+
| X           O  O |   | O     O        O | | 2 |
| X           O    |   | O                | +---+
|                  |   |                  |
|                  | X |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   |                  |
|                  |   |                  |
| O           X    |   | X  X  X  X       |
| O     O     X    |   | X  X  X  X       |
+13-14-15-16-17-18------19-20-21-22-23-24-+
Pip count  X: 136  O: 107 X-O: 2-0/7
Cube: 2, O own cube
O on roll, cube action

Analyzed in Rollout
No redouble
  Player Winning Chances:   76.58% (G:29.31% B:0.25%)
  Opponent Winning Chances: 23.42% (G:3.12% B:0.15%)
Redouble/Take
  Player Winning Chances:   74.82% (G:34.24% B:0.94%)
  Opponent Winning Chances: 25.18% (G:4.48% B:0.49%)

Cubeless Equities: No Double=+0.831, Double=+1.951

Cubeful Equities:
       No redouble:     +1.108
       Redouble/Take:   +1.888 (+0.780)
       Redouble/Pass:   +1.000 (-0.108)

Best Cube action: Too good to redouble / Pass
Percentage of wrong take needed to make the double decision right: 12.2%

Rollout:
  1296 Games rolled with Variance Reduction.
  Moves: 3-ply, cube decisions: XG Roller
  Confidence No Double: ± 0.006 (+1.103..+1.114)
  Confidence Double:    ± 0.011 (+1.877..+1.899)

  Double Decision confidence: 100.0%
  Take Decision confidence: 100.0%

  Duration: 23 minutes 42 seconds

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

///////////////variant - scores reversed //////////////////////////

XGID=---BBBB-B-a-bC---cbcAb--bA:1:-1:-1:00:0:2:0:7:10
X:Player 1   O:Player 2

Score is X:0 O:2 7 pt.(s) match.
+12-11-10--9--8--7-------6--5--4--3--2--1-+
| X           O  O |   | O  X  O        O | +---+
| X           O  O |   | O     O        O | | 2 |
| X           O    |   | O                | +---+
|                  |   |                  |
|                  | X |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   |                  |
|                  |   |                  |
| O           X    |   | X  X  X  X       |
| O     O     X    |   | X  X  X  X       |
+13-14-15-16-17-18------19-20-21-22-23-24-+
Pip count  X: 136  O: 107 X-O: 0-2/7
Cube: 2, O own cube
O on roll, cube action

Analyzed in XG Roller++
Player Winning Chances:   77.24% (G:29.45% B:0.29%)
Opponent Winning Chances: 22.76% (G:2.86% B:0.09%)

Cubeless Equities: No Double=+0.839, Double=+1.307

Cubeful Equities:
       No redouble:     +0.950 (-0.033)
       Redouble/Take:   +0.983
       Redouble/Pass:   +1.000 (+0.017)

Best Cube action: Redouble / Take

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

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