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  • Somewhat awkward 51 to play

    From Timothy Chow@21:1/5 to All on Sat Jul 16 22:40:40 2022
    XGID=-BA--BBbB----D-abcbcbB----:0:0:1:51:0:0:0:0:10

    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 X |
    | X O O O | | O O X |
    | X O | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | X O | | X X X |
    | X O | | X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 136 O: 130 X-O: 0-0
    Cube: 1
    X to play 51

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Tue Jul 19 00:31:35 2022
    XGID=-BA--BBbB----D-abcbcbB----:0:0:1:51:0:0:0:0:10

    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 X |
    | X O O O | | O O X |
    | X O | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | X O | | X X X |
    | X O | | X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 136 O: 130 X-O: 0-0
    Cube: 1
    X to play 51

    After seeing the previous problem ("Mutual holding game") where X
    volunteered a double direct shot, you might be tempted to play 8/2
    in this position. But XG says that 8/2 is a whopper with cheese.
    Instead, XG favors the totally safe and ugly-looking 13/8 6/5.
    In this position, O has no blots in her board, and getting another
    checker sent behind O's five-prime would be bad.

    1. Rollout¹ 13/8 6/5 eq:-0.513
    Player: 35.11% (G:5.74% B:0.11%)
    Opponent: 64.89% (G:7.98% B:0.27%)
    Confidence: ±0.012 (-0.525..-0.501) - [99.9%]

    2. Rollout¹ 13/8 5/4 eq:-0.539 (-0.026)
    Player: 34.36% (G:6.46% B:0.12%)
    Opponent: 65.64% (G:8.97% B:0.40%)
    Confidence: ±0.012 (-0.551..-0.527) - [0.1%]

    3. Rollout¹ 13/8 2/1 eq:-0.585 (-0.072)
    Player: 33.63% (G:3.15% B:0.06%)
    Opponent: 66.37% (G:7.46% B:0.25%)
    Confidence: ±0.012 (-0.597..-0.573) - [0.0%]

    4. Rollout¹ 8/2 eq:-0.636 (-0.123)
    Player: 32.03% (G:5.20% B:0.07%)
    Opponent: 67.97% (G:9.08% B:0.36%)
    Confidence: ±0.010 (-0.646..-0.626) - [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)