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  • 5a 5a 3-4 backgame cube action

    From ah....Clem@21:1/5 to All on Tue Jul 11 15:35:43 2023
    XGID=---BBCC-A---------fedBB---:0:0:-1:00:0:0:0:5:10

    X:X O:O
    Score is X:0 O:0 5 pt.(s) match.
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O |
    | | | O O O O |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | 6 | | X |
    | X | | X X |
    | X | | X X |
    | X | | X X O O |
    | X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 92 O: 141 X-O: 0-0/5
    Cube: 1
    X on roll, cube action




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

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to ah....Clem on Tue Jul 11 20:35:21 2023
    On 7/11/2023 3:35 PM, ah....Clem wrote:
    XGID=---BBCC-A---------fedBB---:0:0:-1:00:0:0:0:5:10

    X:X   O:O
    Score is X:0 O:0 5 pt.(s) match.
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     |             O    |   | O  O  O  O       |
     |                  |   | O  O  O  O       |
     |                  |   | O  O             |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                6 |   | X                |
     |                X |   | X  X             |
     |                X |   | X  X             |
     |                X |   | X  X  O  O       |
     |                X |   | X  X  O  O       |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 92  O: 141 X-O: 0-0/5
    Cube: 1
    X on roll, cube action

    I'd pass this one. O's timing is poor, and her 3-5 backgame is not
    going to generate shots any time soon. Only 3's are awkward for X,
    and I don't think that's enough for a take.

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to All on Thu Jul 13 10:33:19 2023
    The usual advice is to cube a backgame when you have three points to
    clear in front of it. Sometimes it's a take, sometimes a pass, but the standard dictum says ship it, which X did OTB and XG says is correct.

    What about the take? Not enough timing to hold the anchor without the
    board crunching and as Tim observes no immediate blotting rolls. Seemed
    like a pass to me (which is what I did Otb), but XG begs to differ.

    Why might that be?

    Well, I see O being forced off one of the anchors fairly soon, leaving a
    nasty gap while her board stays strong. And due to the advanced nature
    of a 4-3 backgame there aren't that many gammons. That's the best I've got.

    Rollout says it's a very small .019 error to pass, while XGR++ says
    passing is a medium sized .059 error. I'm not including a variant since
    given how small the take is, seems like just about any improvement for X
    would be a pass.

    XGID=---BBCC-A---------fedBB---:0:0:-1:00:0:0:0:5:10

    X:Player 2 O:Player 1
    Score is X:0 O:0 5 pt.(s) match.
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O |
    | | | O O O O |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | 6 | | X |
    | X | | X X |
    | X | | X X |
    | X | | X X O O |
    | X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 92 O: 141 X-O: 0-0/5
    Cube: 1
    X on roll, cube action

    Analyzed in Rollout
    No double
    Player Winning Chances: 73.29% (G:13.05% B:0.20%)
    Opponent Winning Chances: 26.71% (G:2.19% B:0.07%)
    Double/Take
    Player Winning Chances: 73.61% (G:12.53% B:0.19%)
    Opponent Winning Chances: 26.39% (G:2.16% B:0.08%)

    Cubeless Equities: No Double=+0.567, Double=+1.166

    Cubeful Equities:
    No double: +0.928 (-0.053)
    Double/Take: +0.981
    Double/Pass: +1.000 (+0.019)

    Best Cube action: Double / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.009 (+0.919..+0.938)
    Confidence Double: ± 0.013 (+0.968..+0.994)

    Double Decision confidence: 100.0%
    Take Decision confidence: 99.8%

    Duration: 3 minutes 54 seconds

    eXtreme Gammon Version: 2.10, MET: Kazaross XG2



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

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