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  • Hit, of course 2

    From Timothy Chow@21:1/5 to All on Tue Aug 8 08:41:35 2023
    XGID=-Aa-BBCBBb--aB---bcc-baA--:1:-1:1:31:0:0:0:0:10

    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 | | 2 |
    | O | | O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X X | | X X X |
    | O O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 116 O: 134 X-O: 0-0
    Cube: 2, O own cube
    X to play 31

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Thu Aug 10 08:56:09 2023
    XGID=-Aa-BBCBBb--aB---bcc-baA--:1:-1:1:31:0:0:0:0:10

    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 | | 2 |
    | O | | O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X X | | X X X |
    | O O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 116 O: 134 X-O: 0-0
    Cube: 2, O own cube
    X to play 31

    Usually, hitting a blot in the opponent's inner board is better than
    hitting a blot in your own outer board; it gains more pips, and
    interferes with the opponent's board-building. But here, I think
    the point is that it's more important to try to escape the straggler.

    On the other hand, maybe there's something more going on that I don't
    see. In the variant, I would have thought that 23/22* would have been mandatory, but XG says it's very close.

    1. Rollout¹ 23/20 13/12* eq:+0.474
    Player: 68.29% (G:30.90% B:1.53%)
    Opponent: 31.71% (G:9.43% B:0.64%)
    Confidence: ±0.010 (+0.464..+0.483) - [100.0%]

    2. Rollout¹ 23/22* 13/10 eq:+0.350 (-0.124)
    Player: 62.98% (G:32.32% B:1.68%)
    Opponent: 37.02% (G:9.74% B:0.54%)
    Confidence: ±0.010 (+0.340..+0.360) - [0.0%]

    3. Rollout¹ 13/10 13/12* eq:+0.349 (-0.124)
    Player: 63.03% (G:32.54% B:1.54%)
    Opponent: 36.97% (G:9.96% B:0.63%)
    Confidence: ±0.010 (+0.339..+0.359) - [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=-Aa-BBCBBb--aB---bbbbbaA--:1:-1:1:31:0:0:0:0:10

    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 O X | +---+
    | X O O | | O O O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X X | | X X X |
    | O O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 116 O: 131 X-O: 0-0
    Cube: 2, O own cube
    X to play 31

    1. Rollout¹ 23/22* 13/10 eq:-0.161
    Player: 48.12% (G:22.23% B:0.88%)
    Opponent: 51.88% (G:14.57% B:0.83%)
    Confidence: ±0.009 (-0.169..-0.152) - [91.1%]

    2. Rollout¹ 13/10 13/12* eq:-0.171 (-0.010)
    Player: 47.47% (G:24.22% B:1.39%)
    Opponent: 52.53% (G:15.05% B:0.91%)
    Confidence: ±0.012 (-0.183..-0.159) - [8.9%]

    3. Rollout¹ 23/22* 8/5 eq:-0.190 (-0.029)
    Player: 46.73% (G:24.95% B:1.17%)
    Opponent: 53.27% (G:15.54% B:0.79%)
    Confidence: ±0.009 (-0.199..-0.180) - [0.0%]

    ¹ 2592 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 Mon Aug 14 17:45:44 2023
    On 8/8/2023 8:41 AM, Timothy Chow wrote:
    XGID=-Aa-BBCBBb--aB---bcc-baA--:1:-1:1:31:0:0:0:0:10

    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          | | 2 |
     |                O |   | O                | +---+
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |   | X                |
     |          O  X  X |   | X  X  X          |
     | O        O  X  X |   | X  X  X     O  X |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 116  O: 134 X-O: 0-0
    Cube: 2, O own cube
    X to play 31

    X has a nice prime going, but risks it crunching before he can spring
    the runner. So, I'll try stepping up to the edge. Then hitting on the
    12 point looks better than breaking the prime or leaving a second
    homeboard blot.

    So, 23/20 13/12*, but I won't be surprised if slotting the front of the
    prime with 6/3 is the bot play.

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

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