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  • Tim's turn to make a liar out of me

    From [email protected]@21:1/5 to All on Wed Aug 18 03:27:10 2021
    Based on past history, I do think that Tim is (perhaps only slightly) more likely than not to get this problem wrong. However, if the result is ultra-marginal, there's full credit for saying so, and no need to guess
    which side of the border the rollout fell. In other words, I don't care
    about the difference between (for example) 0.997 and 1.003 and
    there is absolutely full credit for saying "ultra-marginal" take/pass
    in this situation.

    Paul

    XGID=baBBBBBB----A----bbdbbA-A-:1:1:1:00:0:0:3:0:10
    X:Daniel O:eXtremeGammon

    Score is X:0 O:0. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O O X X |
    | O O | | O O O |
    | | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | | | +---+
    | X | | X X X X X | | 2 |
    | X X | | X X X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 112 O: 146 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    --- SoupGate-Win32 v1.05
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  • From Timothy Chow@21:1/5 to [email protected] on Wed Aug 18 08:34:50 2021
    On 8/18/2021 6:27 AM, [email protected] wrote:
    XGID=baBBBBBB----A----bbdbbA-A-:1:1:1:00:0:0:3:0:10
    X:Daniel O:eXtremeGammon

    Score is X:0 O:0. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O O X X |
    | O O | | O O O |
    | | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | | | +---+
    | X | | X X X X X | | 2 |
    | X X | | X X X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 112 O: 146 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    These positions tend to be sensitive to how many spare pips X
    has to play. X would like to roll a 2 and two 6's in order to
    escape his back checkers and cruise home to a gammon. If he
    does escape one checker then he gains some more time to escape
    the other. The other thing is that if O enters then X's task
    should become easier because O may have to crunch her board.
    I'm going to go with RD/T, but I expect that one can change
    XG's verdict dramatically by moving X's outfield blot around.

    ---
    Tim Chow

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  • From [email protected]@21:1/5 to Tim Chow on Wed Aug 18 07:37:49 2021
    On Wednesday, August 18, 2021 at 1:34:52 PM UTC+1, Tim Chow wrote:
    On 8/18/2021 6:27 AM, [email protected] wrote:
    XGID=baBBBBBB----A----bbdbbA-A-:1:1:1:00:0:0:3:0:10
    X:Daniel O:eXtremeGammon

    Score is X:0 O:0. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O O X X |
    | O O | | O O O |
    | | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | | | +---+
    | X | | X X X X X | | 2 |
    | X X | | X X X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 112 O: 146 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action
    These positions tend to be sensitive to how many spare pips X
    has to play. X would like to roll a 2 and two 6's in order to
    escape his back checkers and cruise home to a gammon. If he
    does escape one checker then he gains some more time to escape
    the other. The other thing is that if O enters then X's task
    should become easier because O may have to crunch her board.
    I'm going to go with RD/T, but I expect that one can change
    XG's verdict dramatically by moving X's outfield blot around.

    That's correct but XG itself didn't solve this, and wrongly passed my cube. Analyzed in Rollout
    No redouble
    Player Winning Chances: 63.87% (G:39.25% B:2.15%)
    Opponent Winning Chances: 36.13% (G:6.62% B:0.25%)
    Redouble/Take
    Player Winning Chances: 63.73% (G:39.41% B:2.14%)
    Opponent Winning Chances: 36.27% (G:6.67% B:0.26%)

    Cubeless Equities: No Double=+0.623, Double=+1.242

    Cubeful Equities:
    No redouble: +0.815 (-0.114)
    Redouble/Take: +0.929
    Redouble/Pass: +1.000 (+0.071)

    Best Cube action: Redouble / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.012 (+0.803..+0.827)
    Confidence Double: ± 0.019 (+0.910..+0.948)

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

    Duration: 23 minutes 41 seconds

    eXtreme Gammon Version: 2.10

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