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  • Another early(ish) game checker play

    From Timothy Chow@21:1/5 to All on Tue Oct 25 07:41:55 2022
    XGID=----a-E-D---dE-A-cadb-----:0:0:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X X O O | | O O |
    | X O | | O O |
    | X O | | O |
    | X | | O |
    | X | | |
    | |BAR| |
    | | | X |
    | O X | | X |
    | O X | | X |
    | O X | | X |
    | O X | | X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 142 O: 138 X-O: 0-0
    Cube: 1
    X to play 41

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Wed Oct 26 10:47:13 2022
    On 10/25/2022 7:41 AM, Timothy Chow wrote:
    XGID=----a-E-D---dE-A-cadb-----:0:0:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     | X     X     O  O |   | O  O             |
     | X           O    |   | O  O             |
     | X           O    |   | O                |
     | X                |   | O                |
     | X                |   |                  |
     |                  |BAR|                  |
     |                  |   | X                |
     | O           X    |   | X                |
     | O           X    |   | X                |
     | O           X    |   | X                |
     | O           X    |   | X     O          |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 142  O: 138 X-O: 0-0
    Cube: 1
    X to play 41

    X is outboarded so hitting loose seems like the wrong idea. Race is
    very close. I'm not sure Pottle's law applies if you're already in the outfield, but I'll apply it here and play 15/9.

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

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to ah....Clem on Wed Oct 26 12:49:40 2022
    On Wednesday, October 26, 2022 at 10:47:15 AM UTC-4, ah....Clem wrote:
    On 10/25/2022 7:41 AM, Timothy Chow wrote:
    XGID=----a-E-D---dE-A-cadb-----:0:0:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X X O O | | O O |
    | X O | | O O |
    | X O | | O |
    | X | | O |
    | X | | |
    | |BAR| |
    | | | X |
    | O X | | X |
    | O X | | X |
    | O X | | X |
    | O X | | X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 142 O: 138 X-O: 0-0
    Cube: 1
    X to play 41
    X is outboarded so hitting loose seems like the wrong idea. Race is
    very close. I'm not sure Pottle's law applies if you're already in the outfield, but I'll apply it here and play 15/9.

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

    Illegal and oddly enough, worse than the legal play.

    Stick

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Thu Oct 27 08:37:37 2022
    XGID=----a-E-D---dE-A-cadb-----:0:0:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X X O O | | O O |
    | X O | | O O |
    | X O | | O |
    | X | | O |
    | X | | |
    | |BAR| |
    | | | X |
    | O X | | X |
    | O X | | X |
    | O X | | X |
    | O X | | X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 142 O: 138 X-O: 0-0
    Cube: 1
    X to play 41

    Congratulations to ah_clem for finding the bot play (even though ah_clem mistakenly typed 15/9 rather than 15/10). OTB, I considered most of the
    plays displayed in the rollout below *except* 15/10. I eventually
    decided to hit, but the main non-hitting alternative I pondered was
    15/11 6/5. But 15/10 leaves fewer shots (14 instead of 15, none of
    which are double-hitting rolls) and blots, and duplicates O's sixes.

    1. Rollout¹ 15/10 eq:-0.306
    Player: 40.96% (G:2.95% B:0.06%)
    Opponent: 59.04% (G:8.96% B:0.14%)
    Confidence: ±0.009 (-0.315..-0.297) - [100.0%]

    2. Rollout¹ 8/4* 4/3 eq:-0.350 (-0.044)
    Player: 42.07% (G:4.90% B:0.15%)
    Opponent: 57.93% (G:15.05% B:0.36%)
    Confidence: ±0.010 (-0.360..-0.341) - [0.0%]

    3. Rollout¹ 15/11 6/5 eq:-0.427 (-0.121)
    Player: 38.99% (G:3.06% B:0.10%)
    Opponent: 61.01% (G:10.29% B:0.27%)
    Confidence: ±0.011 (-0.438..-0.416) - [0.0%]

    4. Rollout¹ 13/8 eq:-0.434 (-0.128)
    Player: 38.88% (G:3.58% B:0.14%)
    Opponent: 61.12% (G:11.39% B:0.22%)
    Confidence: ±0.010 (-0.444..-0.423) - [0.0%]

    5. Rollout¹ 8/3 eq:-0.442 (-0.136)
    Player: 38.62% (G:3.74% B:0.11%)
    Opponent: 61.38% (G:11.73% B:0.26%)
    Confidence: ±0.010 (-0.452..-0.432) - [0.0%]

    6. Rollout¹ 15/11 8/7 eq:-0.457 (-0.151)
    Player: 37.64% (G:2.96% B:0.09%)
    Opponent: 62.36% (G:10.07% B:0.24%)
    Confidence: ±0.009 (-0.466..-0.447) - [0.0%]

    7. Rollout¹ 15/14 6/2 eq:-0.462 (-0.156)
    Player: 37.64% (G:2.76% B:0.07%)
    Opponent: 62.36% (G:10.83% B:0.22%)
    Confidence: ±0.008 (-0.470..-0.454) - [0.0%]

    8. Rollout¹ 15/14 8/4* eq:-0.485 (-0.180)
    Player: 38.74% (G:4.84% B:0.15%)
    Opponent: 61.26% (G:17.28% B:0.42%)
    Confidence: ±0.009 (-0.495..-0.476) - [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

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