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  • 4pt or hit?

    From Timothy Chow@21:1/5 to All on Mon Oct 23 08:58:02 2023
    XGID=-aB--BCBA-A-b--C-babAbabb-:1:1:1:62:0:0:0:0:10

    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 O O O |
    | X O | | O O O O |
    | X | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O X | | X X X | | 2 |
    | O X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 129 O: 102 X-O: 0-0
    Cube: 2, X own cube
    X to play 62

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed Oct 25 22:39:05 2023
    XGID=-aB--BCBA-A-b--C-babAbabb-:1:1:1:62:0:0:0:0:10

    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 O O O |
    | X O | | O O O O |
    | X | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O X | | X X X | | 2 |
    | O X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 129 O: 102 X-O: 0-0
    Cube: 2, X own cube
    X to play 62

    The top three plays in the rollout below are closer in equity than in
    most of the problems I post here, but I didn't play any of them, opting
    instead for 20/18* 15/9. Evidently, that's too loose a play. Have a
    look at the variant for comparison.

    1. Rollout¹ 10/4 6/4 eq:+0.477
    Player: 61.25% (G:16.51% B:1.05%)
    Opponent: 38.75% (G:18.44% B:0.17%)
    Confidence: ±0.014 (+0.463..+0.491) - [100.0%]

    2. Rollout¹ 20/18* 8/2 eq:+0.444 (-0.032)
    Player: 58.08% (G:19.99% B:0.93%)
    Opponent: 41.92% (G:17.69% B:0.32%)
    Confidence: ±0.010 (+0.434..+0.454) - [0.0%]

    3. Rollout¹ 20/18* 7/1* eq:+0.439 (-0.037)
    Player: 58.36% (G:31.60% B:0.87%)
    Opponent: 41.64% (G:24.81% B:2.92%)
    Confidence: ±0.011 (+0.429..+0.450) - [0.0%]

    4. Rollout¹ 20/18* 15/9 eq:+0.374 (-0.103)
    Player: 58.72% (G:23.40% B:1.45%)
    Opponent: 41.28% (G:23.93% B:1.77%)
    Confidence: ±0.009 (+0.365..+0.382) - [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=-aB--BCBA-A-b---CbabAbabb-:1:1:1:62:0:0:0:0:10

    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 O O O |
    | X O | | O O O O |
    | X | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O X | | X X X | | 2 |
    | O X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 132 O: 102 X-O: 0-0
    Cube: 2, X own cube
    X to play 62

    1. Rollout¹ 20/18* 16/10 eq:+0.564
    Player: 62.38% (G:23.33% B:1.49%)
    Opponent: 37.62% (G:16.57% B:0.29%)
    Confidence: ±0.010 (+0.554..+0.574) - [100.0%]

    2. Rollout¹ 10/4 6/4 eq:+0.432 (-0.132)
    Player: 59.69% (G:16.09% B:1.00%)
    Opponent: 40.31% (G:18.11% B:0.16%)
    Confidence: ±0.011 (+0.421..+0.443) - [0.0%]

    3. Rollout¹ 20/18* 7/1* eq:+0.414 (-0.150)
    Player: 57.31% (G:30.79% B:0.85%)
    Opponent: 42.69% (G:25.66% B:2.74%)
    Confidence: ±0.013 (+0.401..+0.427) - [0.0%]

    4. Rollout¹ 20/18* 8/2 eq:+0.414 (-0.150)
    Player: 57.20% (G:19.84% B:1.02%)
    Opponent: 42.80% (G:17.37% B:0.23%)
    Confidence: ±0.012 (+0.402..+0.426) - [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 Fri Oct 27 11:42:07 2023
    On 10/23/2023 8:58 AM, Timothy Chow wrote:
    XGID=-aB--BCBA-A-b--C-babAbabb-:1:1:1:62:0:0:0:0:10

    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  O  O  O |  |       X     O    |   | O     O     O  O |  |       X          |   |                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |   | X                | +---+
     | O              X |   | X  X        X    | | 2 |  | O     X     X  X |   | X  X        X  O | +---+  +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 129  O: 102 X-O: 0-0
    Cube: 2, X own cube
    X to play 62

    Hitting escapes with tempo, while making the four point is a permanent
    asset and with a 50 pip lead X doesn't need more of a lead to win. But
    with 11 in the zone, a three point board, and one on the roof the gammon
    wins seem to make the hitting play worth it.

    Should X whack two? If we're hitting it looks better than 10/4 or 8/2.

    20/18* 7/1*.

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