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  • Only two legal moves

    From Timothy Chow@21:1/5 to All on Thu Aug 11 09:17:24 2022
    XGID=aBADB-b-Ab----A--bbbbb----:1:-1:1:54:0:0:0:0:10

    X:Player 1 O:Player 2
    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 | +---+
    | O O | | O O O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | | X |
    | | | X |
    | O | | O X X X |
    | O X | | O X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 46 O: 155 X-O: 0-0
    Cube: 2, O own cube
    X to play 54

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sat Aug 13 09:35:08 2022
    XGID=aBADB-b-Ab----A--bbbbb----:1:-1:1:54:0:0:0:0:10

    X:Player 1 O:Player 2
    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 | +---+
    | O O | | O O O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | | X |
    | | | X |
    | O | | O X X X |
    | O X | | O X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 46 O: 155 X-O: 0-0
    Cube: 2, O own cube
    X to play 54

    One's first instinct is that 14/10 8/3 is the safer play, but if
    you count shots, you'll find that O has 20 hitting rolls after either
    play. It might seem that getting hit twice, or having three blots
    lying around, is worse, but X can't be gammoned and O owns the cube,
    so to a first approximation you can think of getting hit as being a
    simple loss regardless of how many blots get hit. The key point is
    that after 14/5, it's much easier for X to clean up if he is *not*
    hit. That makes 14/5 the better play.

    1. Rollout¹ 14/5 eq:+0.261
    Player: 52.83% (G:42.77% B:0.10%)
    Opponent: 47.17% (G:0.00% B:0.00%)
    Confidence: ±0.006 (+0.254..+0.267) - [100.0%]

    2. Rollout¹ 14/10 8/3 eq:+0.122 (-0.138)
    Player: 49.69% (G:37.63% B:0.08%)
    Opponent: 50.31% (G:0.00% B:0.00%)
    Confidence: ±0.008 (+0.114..+0.131) - [0.0%]

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

    eXtreme Gammon Version: 2.19.207.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 Aug 13 12:34:53 2022
    On 8/11/2022 9:17 AM, Timothy Chow wrote:
    XGID=aBADB-b-Ab----A--bbbbb----:1:-1:1:54:0:0:0:0:10

    X:Player 1   O:Player 2
    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          | +---+
     |             O  O |   | O  O  O          | | 2 |
     |                  |   |                  | +---+
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  | O |                  |
     |                  |   |          X       |
     |                  |   |          X       |
     |          O       |   | O     X  X     X |
     |          O  X    |   | O     X  X  X  X |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 46  O: 155 X-O: 0-0
    Cube: 2, O own cube
    X to play 54

    I suck at shot counting, but 14/10 8/3 seems to leave fewer shots so
    I'll go with that. I'm at least 50% to get this one right.


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

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