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  • 7-away/6-away recube

    From Timothy Chow@21:1/5 to All on Thu Jun 22 08:17:47 2023
    Note that O has already borne off five checkers.

    XGID=a-CDCBB----------------de-:1:1:1:00:0:1:0:7:10

    Score is X:0 O:1 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
    | |BAR| |
    | | O | |
    | | | X |
    | | | X 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: 52 O: 38 X-O: 0-1/7
    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 Fri Jun 23 18:50:59 2023
    On 6/22/2023 8:17 AM, Timothy Chow wrote:
    Note that O has already borne off five checkers.

    XGID=a-CDCBB----------------de-:1:1:1:00:0:1:0:7:10

    Score is X:0 O:1 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
     |                  |BAR|                  |
     |                  | O |                  |
     |                  |   |          X       |
     |                  |   |       X  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: 52  O: 38 X-O: 0-1/7
    Cube: 2, X own cube
    X on roll, cube action



    If O was closed out she'd have about a 23% chance of winning. She has a
    bit more than that since an immediate 16 sends her on the way a few
    rolls earlier. The takepoint AtS is 22% (no gammons) so the take seems
    clear. I don't think it's enough to hold. Any double looks like a
    market loser, although 65 and 54 are bad rolls. Seems like R/T to me.

    --
    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 All on Sat Jun 24 08:13:17 2023
    XGID=a-CDCBB----------------de-:1:1:1:00:0:1:0:7:10

    Score is X:0 O:1 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
    | |BAR| |
    | | O | |
    | | | X |
    | | | X 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: 52 O: 38 X-O: 0-1/7
    Cube: 2, X own cube
    X on roll, cube action

    Holding a 2-cube while trailing usually means you should rewhip to 4
    very quickly when you smell market losers---at least if you have any
    gammon chances. Here, though, gammons are impossible. X should still
    redouble a little more aggressively than for money, but here he has an
    awkward gap on his 1pt and a front-loaded position. That means he
    risks exposing a blot and getting hit, not just on this turn but on
    subsequent turns, because it's not easy for him to eliminate that gap.
    XG says it's a blunder to redouble here. For comparison, see the
    variant below.

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 68.24% (G:0.00% B:0.00%)
    Opponent Winning Chances: 31.76% (G:0.00% B:0.00%)
    Redouble/Take
    Player Winning Chances: 68.29% (G:0.00% B:0.00%)
    Opponent Winning Chances: 31.71% (G:0.00% B:0.00%)

    Cubeful Equities:
    No redouble: +0.718
    Redouble/Take: +0.632 (-0.086)
    Redouble/Pass: +1.000 (+0.282)

    Best Cube action: No redouble / Take
    Percentage of wrong pass needed to make the double decision right: 23.4%

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.004 (+0.715..+0.722)
    Confidence Double: ± 0.005 (+0.627..+0.637)

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

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

    XGID=a-CCCCB----------------de-:1:1:1:00:0:1:0:7:10

    Score is X:0 O:1 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
    | |BAR| |
    | | O | |
    | | | |
    | | | X X 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: 54 O: 38 X-O: 0-1/7
    Cube: 2, X own cube
    X on roll, cube action

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 72.53% (G:0.00% B:0.00%)
    Opponent Winning Chances: 27.47% (G:0.00% B:0.00%)
    Redouble/Take
    Player Winning Chances: 72.59% (G:0.00% B:0.00%)
    Opponent Winning Chances: 27.41% (G:0.00% B:0.00%)

    Cubeful Equities:
    No redouble: +0.832 (-0.006)
    Redouble/Take: +0.838
    Redouble/Pass: +1.000 (+0.162)

    Best Cube action: Redouble / Take

    Rollout:
    5184 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 4-ply, cube decisions: XG Roller+
    Search interval: Large
    Confidence No Double: ± 0.001 (+0.831..+0.833)
    Confidence Double: ± 0.002 (+0.836..+0.840)

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

    ---
    Tim Chow

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