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  • Something has to give

    From Timothy Chow@21:1/5 to All on Thu Jun 1 07:48:52 2023
    XGID=-Bb-DBB-B---b-----BbbbcbA-:1:1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O O O X |
    | X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X | +---+
    | O X | | X X X O X | | 2 |
    | O X | | X X X O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 116 O: 115 X-O: 0-0
    Cube: 2, X own cube
    X to play 41

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sat Jun 3 07:58:13 2023
    XGID=-Bb-DBB-B---b-----BbbbcbA-:1:1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O O O X |
    | X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X | +---+
    | O X | | X X X O X | | 2 |
    | O X | | X X X O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 116 O: 115 X-O: 0-0
    Cube: 2, X own cube
    X to play 41

    I made the play that I thought would minimize shots: 8/7 8/4. But
    O will hit on her ace point with a 2, so 18/17 18/14 duplicates 2's,
    as well as O's 5's to escape her back checkers. It still looks
    dangerous to expose two new blots rather than one, but at least
    X keeps his 8pt asset, and creates some root numbers. After 18/17
    18/14, consider what happens if O rolls 64 63 43 31, or even 61.
    After 8/7 8/4, the only roll for O that I would consider to be an
    anti-joker is 31.

    It would be a different story if O's spare on her 3pt were on her
    midpoint instead. See the variant below.

    1. Rollout¹ 18/17 18/14 eq:-0.532
    Player: 31.93% (G:10.00% B:0.54%)
    Opponent: 68.07% (G:37.11% B:2.18%)
    Confidence: ±0.008 (-0.541..-0.524) - [100.0%]

    2. Rollout¹ 8/7 8/4 eq:-0.705 (-0.173)
    Player: 26.82% (G:8.36% B:0.40%)
    Opponent: 73.18% (G:41.40% B:1.49%)
    Confidence: ±0.008 (-0.713..-0.697) - [0.0%]

    3. Rollout¹ 18/13 eq:-0.745 (-0.212)
    Player: 26.73% (G:8.23% B:0.38%)
    Opponent: 73.27% (G:43.62% B:2.66%)
    Confidence: ±0.008 (-0.753..-0.737) - [0.0%]

    4. Rollout¹ 5/4 5/1 eq:-0.756 (-0.223)
    Player: 23.88% (G:4.81% B:0.10%)
    Opponent: 76.12% (G:35.88% B:1.19%)
    Confidence: ±0.008 (-0.763..-0.748) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

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

    XGID=-Bb-DBB-B---c-----BbbbbbA-:1:1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O O O X |
    | X | | O O O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | O | | X | +---+
    | O X | | X X X O X | | 2 |
    | O X | | X X X O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 116 O: 125 X-O: 0-0
    Cube: 2, X own cube
    X to play 41

    1. Rollout¹ 8/7 8/4 eq:-0.690
    Player: 26.18% (G:7.58% B:0.31%)
    Opponent: 73.82% (G:37.18% B:1.47%)
    Confidence: ±0.008 (-0.698..-0.682) - [100.0%]

    2. Rollout¹ 5/4 5/1 eq:-0.728 (-0.037)
    Player: 24.85% (G:5.11% B:0.11%)
    Opponent: 75.15% (G:35.76% B:1.43%)
    Confidence: ±0.008 (-0.736..-0.720) - [0.0%]

    3. Rollout¹ 18/17 18/14 eq:-0.785 (-0.095)
    Player: 24.06% (G:6.23% B:0.29%)
    Opponent: 75.94% (G:39.92% B:2.41%)
    Confidence: ±0.008 (-0.793..-0.777) - [0.0%]

    4. Rollout¹ 18/13 eq:-0.792 (-0.102)
    Player: 24.00% (G:6.17% B:0.29%)
    Opponent: 76.00% (G:40.16% B:2.47%)
    Confidence: ±0.007 (-0.800..-0.785) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sat Jun 3 14:16:32 2023
    On 6/1/2023 7:48 AM, Timothy Chow wrote:
    XGID=-Bb-DBB-B---b-----BbbbcbA-:1:1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     |                X |   | O  O  O  O  O  X |
     |                X |   | O  O  O  O  O    |
     |                  |   |          O       |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |       X          |
     |                  |   |       X          | +---+
     | O           X    |   | X  X  X     O  X | | 2 |
     | O           X    |   | X  X  X     O  X | +---+
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 116  O: 115 X-O: 0-0
    Cube: 2, X own cube
    X to play 41


    I second checker back leads to a lot of gammon losses, so bold play is
    not indicated. O has a lot of awkward rolls too, so I'll just minimize
    shots by clearing the five point.

    Yeah it's the chicken play. Bwok Bwok.

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

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