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  • 4-away/6-away cube action

    From Timothy Chow@21:1/5 to All on Mon Sep 26 08:29:13 2022
    XGID=----BaD-CBA-dB-a-d-c--A-b-:0:0:1:00:3:1:0:7:10

    Score is X:3 O:1 7 pt.(s) match.
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | X O | | O O |
    | O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | O | | X |
    | O X | | X |
    | O X X | | X X |
    | O X X X | | X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 132 O: 134 X-O: 3-1/7
    Cube: 1
    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 Mon Sep 26 12:33:34 2022
    On 9/26/2022 8:29 AM, Timothy Chow wrote:
    XGID=----BaD-CBA-dB-a-d-c--A-b-:0:0:1:00:3:1:0:7:10

    Score is X:3 O:1 7 pt.(s) match.  +13-14-15-16-17-18------19-20-21-22-23-24-+
     | X     O     O    |   | O        X     O |
     | X           O    |   | O              O |  |             O    |   | O                |  |             O    |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     | O                |   | X                |  | O           X    |   | X                |  | O        X  X    |   | X     X          |
     | O     X  X  X    |   | X  O  X          |  +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 132  O: 134 X-O: 3-1/7
    Cube: 1
    X on roll, cube action

    At 4a, a doubled gammon is quite valuable since it wins the match outright.

    Other than that, the gammonless takepoint for 4a 6a is a fairly normal
    21-22% for both players. Are there enough gammons here to tip it one
    way or the other? Well, 12 in the zone against a single checker can
    make for a successful blitz. I count 16 POH rolls, plus X will probably
    want to hit loose, and I think that only leaves 66 to not hit. Would be
    a shame if X rolled that instead of hitting. (c:


    Is this TG? Maybe, but I see a fair number of sequences where O turns
    it around, so I'll ship it. Race is even and that's usually enough to
    take, but the gammons give me pause, so I'll say pass. And since I'm not
    sure about the take, it must be a cube.

    D/P.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Tue Sep 27 23:34:19 2022
    XGID=----BaD-CBA-dB-a-d-c--A-b-:0:0:1:00:3:1:0:7:10

    Score is X:3 O:1 7 pt.(s) match.
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | X O | | O O |
    | O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | O | | X |
    | O X | | X |
    | O X X | | X X |
    | O X X X | | X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 132 O: 134 X-O: 3-1/7
    Cube: 1
    X on roll, cube action

    I thought this was an easy take for money, and I inferred that it
    would be a take ATS. However, I underestimated X's gammon wins.
    XG says it's a take for money, but much closer than I expected,
    and a big pass ATS. It may be a tempting rule of thumb that when
    you're trailing in the match score, you have more leeway for taking.
    But this rule of thumb has many exceptions, and when the leader
    is 4-away, the trailer has to be cautious about taking gammonish
    cubes. Just because O has only one checker back and X has only a
    two-point board doesn't mean that O is safe from gammons. X has
    12 checkers in the zone, and O has another blot waiting to be
    picked up. O's board is weak and she has a lot of checkers to
    bring home yet.

    Analyzed in Rollout
    No double
    Player Winning Chances: 69.12% (G:26.99% B:0.79%)
    Opponent Winning Chances: 30.88% (G:7.44% B:0.28%)
    Double/Take
    Player Winning Chances: 69.51% (G:27.31% B:1.45%)
    Opponent Winning Chances: 30.49% (G:7.83% B:0.66%)

    Cubeful Equities:
    No double: +0.808 (-0.192)
    Double/Take: +1.147 (+0.147)
    Double/Pass: +1.000

    Best Cube action: Double / Pass

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.010 (+0.797..+0.818)
    Confidence Double: ± 0.017 (+1.130..+1.165)

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

    -----
    Money
    -----

    XGID=----BaD-CBA-dB-a-d-c--A-b-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | X O | | O O |
    | O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | O | | X |
    | O X | | X |
    | O X X | | X X |
    | O X X X | | X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 132 O: 134 X-O: 0-0
    Cube: 1
    X on roll, cube action

    Analyzed in Rollout
    No double
    Player Winning Chances: 69.16% (G:26.89% B:0.63%)
    Opponent Winning Chances: 30.84% (G:7.25% B:0.25%)
    Double/Take
    Player Winning Chances: 69.44% (G:27.20% B:0.73%)
    Opponent Winning Chances: 30.56% (G:7.58% B:0.27%)

    Cubeful Equities:
    No double: +0.772 (-0.171)
    Double/Take: +0.942
    Double/Pass: +1.000 (+0.058)

    Best Cube action: Double / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.010 (+0.761..+0.782)
    Confidence Double: ± 0.016 (+0.926..+0.959)

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

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