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  • 6-away/3-away recube action

    From Timothy Chow@21:1/5 to All on Tue Sep 27 08:30:32 2022
    XGID=-BBBCBB--A---------dabdbbA:1:1:1:00:1:4:0:7:10

    Score is X:1 O:4 7 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 |
    | | | O O |
    | | | O O |
    | | X | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | | | X X X X X X | | 2 |
    | X | | X X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 80 O: 55 X-O: 1-4/7
    Cube: 2, X own cube
    X on roll, cube action

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah...Clem@21:1/5 to Timothy Chow on Tue Sep 27 11:48:23 2022
    On 9/27/2022 8:30 AM, Timothy Chow wrote:
    XGID=-BBBCBB--A---------dabdbbA:1:1:1:00:1:4:0:7:10

    Score is X:1 O:4 7 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 |  |                  |   | O        O       |  |                  |   | O        O       |  |                  | X |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |   |       X          | +---+
     |                  |   | X  X  X  X  X  X | | 2 |  |          X       |   | X  X  X  X  X  X | +---+  +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 80  O: 55 X-O: 1-4/7
    Cube: 2, X own cube
    X on roll, cube action


    I'm not seeing many gammon losses for O, so her recube takepoint is
    about 29%. Clearly she has that.

    X wins outright if he hits, which is about 30%. So there's some logic
    in cubing now due to the 11 market losers. The doubling window opens at
    about 28%, so X is within the doubling window, in theory at least - just
    being in the window doesn't mean the cube is correct.

    I'll ship it here, and of course O should take this. The difference
    between 6aC and already lost is mainly the time spent playing it out,
    not the result.

    RD/T

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Thu Sep 29 08:17:12 2022
    XGID=-BBBCBB--A---------dabdbbA:1:1:1:00:1:4:0:7:10

    Score is X:1 O:4 7 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 |
    | | | O O |
    | | | O O |
    | | X | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | | | X X X X X X | | 2 |
    | X | | X X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 80 O: 55 X-O: 1-4/7
    Cube: 2, X own cube
    X on roll, cube action

    Generally speaking, when you're trailing in the match score and
    are holding a 2-cube, you should be looking to re-whip it to 4
    at the slightest provocation. There are limits to this principle,
    though. I redoubled to 4 here, but XG says that's a blunder. The
    trouble is that X wins essentially zero gammons. The possibility
    of winning the entire match this game is one of the main drivers
    behind recubes ATS. In the variant below, X wins 6% or 7% gammons
    according to XG, and that is just barely enough to make XG recube.

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 34.68% (G:0.99% B:0.01%)
    Opponent Winning Chances: 65.32% (G:1.72% B:0.03%)
    Redouble/Take
    Player Winning Chances: 34.81% (G:0.88% B:0.01%)
    Opponent Winning Chances: 65.19% (G:1.32% B:0.01%)

    Cubeful Equities:
    No redouble: -0.281
    Redouble/Take: -0.370 (-0.089)
    Redouble/Pass: +1.000 (+1.281)

    Best Cube action: No redouble / Take
    Percentage of wrong pass needed to make the double decision right: 6.5%

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.002 (-0.283..-0.280)
    Confidence Double: ± 0.002 (-0.372..-0.368)

    eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

    -------
    Variant
    -------

    XGID=-BBBCBB--A--------acbadbbA:1:1:1:00:1:4:0:7:10

    Score is X:1 O:4 7 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 O |
    | | | O O |
    | | | O |
    | | X | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | | | X X X X X X | | 2 |
    | X | | X X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 80 O: 57 X-O: 1-4/7
    Cube: 2, X own cube
    X on roll, cube action

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 35.73% (G:6.70% B:0.20%)
    Opponent Winning Chances: 64.27% (G:1.74% B:0.01%)
    Redouble/Take
    Player Winning Chances: 35.89% (G:6.54% B:0.22%)
    Opponent Winning Chances: 64.11% (G:1.61% B:0.01%)

    Cubeful Equities:
    No redouble: -0.190 (-0.004)
    Redouble/Take: -0.185
    Redouble/Pass: +1.000 (+1.185)

    Best Cube action: Redouble / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 4-ply, cube decisions: XG Roller+
    Search interval: Large
    Confidence No Double: ± 0.002 (-0.191..-0.188)
    Confidence Double: ± 0.002 (-0.187..-0.184)

    eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

    ---
    Tim Chow

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    * Origin: fsxNet Usenet Gateway (21:1/5)