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  • Your opponent rolled an anti-joker. Now what?

    From Timothy Chow@21:1/5 to All on Sat Oct 28 09:11:34 2023
    XGID=--CBBBC---------aa--bcCec-:1:1:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O X O O |
    | | | O O X O O |
    | | | O X O O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X X | +---+
    | | | X X X X X | | 2 |
    | | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 52 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to Timothy Chow on Sun Oct 29 12:30:51 2023
    On Saturday, October 28, 2023 at 9:12:27 AM UTC-4, Timothy Chow wrote:
    XGID=--CBBBC---------aa--bcCec-:1:1:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O X O O |
    | | | O O X O O |
    | | | O X O O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X X | +---+
    | | | X X X X X | | 2 |
    | | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 52 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    ---
    Tim Chow

    3/4ths of the numbers hit and to simplify we're going to call all of those hits wins. That means the net gammon difference only needs to be around 6% to make this a pass. Seems like a clear pass then.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Mon Oct 30 09:24:12 2023
    XGID=--CBBBC---------aa--bcCec-:1:1:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O X O O |
    | | | O O X O O |
    | | | O X O O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X X | +---+
    | | | X X X X X | | 2 |
    | | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 52 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    It may not even be clear at first that this is a double since the
    cube will be coming right back after X's 9 misses, and X will have
    at best a bare take depending on what he rolls. However, since the
    27 hits are so devastating, X must double now. I thought that this
    should still be a clear take, again because O pretty much always
    wins after a miss, but XG says that the risk of getting gammoned
    is too high. See the two variants for comparison.

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 73.48% (G:22.78% B:0.70%)
    Opponent Winning Chances: 26.52% (G:3.99% B:0.02%)
    Redouble/Take
    Player Winning Chances: 74.05% (G:22.56% B:0.68%)
    Opponent Winning Chances: 25.95% (G:4.09% B:0.02%)

    Cubeful Equities:
    No redouble: +0.787 (-0.213)
    Redouble/Take: +1.111 (+0.111)
    Redouble/Pass: +1.000

    Best Cube action: Redouble / Pass

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.005 (+0.783..+0.792)
    Confidence Double: ± 0.008 (+1.103..+1.119)

    eXtreme Gammon Version: 2.19.211.pre-release

    ---------
    Variant 1
    ---------

    XGID=-ABBBBC---------aa--bcCec-:1:1:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O X O O |
    | | | O O X O O |
    | | | O X O O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | | | X X X X X | | 2 |
    | | | X X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 113 O: 52 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 71.37% (G:24.50% B:0.77%)
    Opponent Winning Chances: 28.63% (G:6.09% B:0.04%)
    Redouble/Take
    Player Winning Chances: 71.77% (G:24.48% B:0.74%)
    Opponent Winning Chances: 28.23% (G:6.37% B:0.05%)

    Cubeful Equities:
    No redouble: +0.730 (-0.270)
    Redouble/Take: +1.015 (+0.015)
    Redouble/Pass: +1.000

    Best Cube action: Redouble / Pass

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.005 (+0.725..+0.735)
    Confidence Double: ± 0.011 (+1.004..+1.025)

    eXtreme Gammon Version: 2.19.211.pre-release

    ---------
    Variant 2
    ---------

    XGID=--CBBBC---------a-a-bcCec-:1:1:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O X O O |
    | | | O O X O O |
    | | | O X O O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X X | +---+
    | | | X X X X X | | 2 |
    | | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 51 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 68.39% (G:20.73% B:0.69%)
    Opponent Winning Chances: 31.61% (G:4.51% B:0.02%)
    Redouble/Take
    Player Winning Chances: 68.98% (G:20.52% B:0.65%)
    Opponent Winning Chances: 31.02% (G:4.69% B:0.03%)

    Cubeful Equities:
    No redouble: +0.665 (-0.198)
    Redouble/Take: +0.864
    Redouble/Pass: +1.000 (+0.136)

    Best Cube action: Redouble / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.005 (+0.661..+0.670)
    Confidence Double: ± 0.008 (+0.855..+0.872)

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)