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  • Blitz vs. prime

    From Timothy Chow@21:1/5 to All on Tue Feb 28 09:26:45 2023
    XGID=aAaBBCBB--a-Aa-aacbbb-AA--:1:-1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O O O | | O O X X | +---+
    | O O | | O O | | 2 |
    | O | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | | |
    | | | X |
    | X | | X X X X |
    | X O X | | X X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 113 O: 154 X-O: 0-0
    Cube: 2, O own cube
    X to play 41

    --
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Timothy Chow on Tue Feb 28 10:11:43 2023
    On Tuesday, February 28, 2023 at 9:26:47 AM UTC-5, Timothy Chow wrote:
    XGID=aAaBBCBB--a-Aa-aacbbb-AA--:1:-1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O O O | | O O X X | +---+
    | O O | | O O | | 2 |
    | O | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | | |
    | | | X |
    | X | | X X X X |
    | X O X | | X X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 113 O: 154 X-O: 0-0
    Cube: 2, O own cube
    X to play 41

    --
    Tim Chow

    I look at the opponent holding the doubling cube and think that, if priming and blitzing are equally viable, then priming is preferred to avoid getting back to the opponent's doubling window. So my first bet would be on blitzing. Looking at the position,
    it looks like O has a great shot at outperforming us in a priming battle based on our risk for crunching and on his well-place outfield checkers.
    Admittedly, my problem is figuring out what the best blitzing play is, and I'm not sure my blitzing and priming plays would be different..... I'm guessing what distinguishes a priming play here is using the 1 to get to the edge of the prime and bring
    that/those checkers around. They're needed for a prime given the blot on the ace point and spare on 5.

    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Thu Mar 2 07:26:13 2023
    XGID=---a-BCBB-A-bBa--bbbcB-bA-:1:1:1:55:0:0:0:0:10

    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 O X |
    | X O O | | O O X O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O X X | | X X | | 2 |
    | O X X X | | X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 160 O: 120 X-O: 0-0
    Cube: 2, X own cube
    X to play 55

    Like Bob, I played 21/16(2), 8/3*(2). But X is still way behind in the
    pip count after this roll, and 21/16(2) somewhat strands his straggler.
    See the variant below for comparison.

    1. Rollout¹ 13/3*(2) eq:+0.294
    Player: 52.75% (G:14.82% B:0.49%)
    Opponent: 47.25% (G:12.19% B:0.61%)
    Confidence: ±0.010 (+0.283..+0.304) - [100.0%]

    2. Rollout¹ 21/16(2) 8/3*(2) eq:+0.181 (-0.113)
    Player: 50.58% (G:15.47% B:0.66%)
    Opponent: 49.42% (G:18.00% B:0.74%)
    Confidence: ±0.010 (+0.171..+0.190) - [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=---a-BCBB-A-bCa--bbbcB-b--:1:1:1:55:0:0:0:0:10

    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 O |
    | X O O | | O O X O |
    | X | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O X X | | X X | | 2 |
    | O X X X | | X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 149 O: 120 X-O: 0-0
    Cube: 2, X own cube
    X to play 55

    1. Rollout¹ 21/16(2) 8/3*(2) eq:+0.595
    Player: 62.57% (G:13.59% B:0.39%)
    Opponent: 37.43% (G:7.39% B:0.23%)
    Confidence: ±0.007 (+0.587..+0.602) - [100.0%]

    2. Rollout¹ 13/3*(2) eq:+0.566 (-0.029)
    Player: 61.69% (G:16.07% B:0.46%)
    Opponent: 38.31% (G:7.91% B:0.28%)
    Confidence: ±0.014 (+0.552..+0.580) - [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 Robert Zimmerman@21:1/5 to Timothy Chow on Thu Mar 2 06:26:32 2023
    On Thursday, March 2, 2023 at 7:26:14 AM UTC-5, Timothy Chow wrote:
    XGID=---a-BCBB-A-bBa--bbbcB-bA-:1:1:1:55:0:0:0:0:10
    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 O X |
    | X O O | | O O X O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O X X | | X X | | 2 |
    | O X X X | | X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 160 O: 120 X-O: 0-0
    Cube: 2, X own cube
    X to play 55

    Like Bob, I played 21/16(2), 8/3*(2). But X is still way behind in the
    pip count after this roll, and 21/16(2) somewhat strands his straggler.
    See the variant below for comparison.

    1. Rollout¹ 13/3*(2) eq:+0.294
    Player: 52.75% (G:14.82% B:0.49%)
    Opponent: 47.25% (G:12.19% B:0.61%)
    Confidence: ±0.010 (+0.283..+0.304) - [100.0%]

    2. Rollout¹ 21/16(2) 8/3*(2) eq:+0.181 (-0.113)
    Player: 50.58% (G:15.47% B:0.66%)
    Opponent: 49.42% (G:18.00% B:0.74%)
    Confidence: ±0.010 (+0.171..+0.190) - [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=---a-BCBB-A-bCa--bbbcB-b--:1:1:1:55:0:0:0:0:10
    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 O |
    | X O O | | O O X O |
    | X | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O X X | | X X | | 2 |
    | O X X X | | X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 149 O: 120 X-O: 0-0
    Cube: 2, X own cube
    X to play 55

    1. Rollout¹ 21/16(2) 8/3*(2) eq:+0.595
    Player: 62.57% (G:13.59% B:0.39%)
    Opponent: 37.43% (G:7.39% B:0.23%)
    Confidence: ±0.007 (+0.587..+0.602) - [100.0%]

    2. Rollout¹ 13/3*(2) eq:+0.566 (-0.029)
    Player: 61.69% (G:16.07% B:0.46%)
    Opponent: 38.31% (G:7.91% B:0.28%)
    Confidence: ±0.014 (+0.552..+0.580) - [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

    You scrambled your threads, Tim.
    :-)

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to Robert Zimmerman on Fri Mar 3 23:42:34 2023
    On 3/2/2023 9:26 AM, Robert Zimmerman wrote:
    You scrambled your threads, Tim.
    :-)

    Whoops! You're right, of course. Here's the rollout of the
    correct position. I spent most of my time trying to decide
    between 7/2* and 22/21 5/1. The bot play of 6/2*/1 is a type
    of play that I'd seen before, but it didn't seem to be the
    right idea here since it sacrifices X's priming potential.
    What I found even more surprising was that in the variant
    below, where I've advanced X's checker on his 23pt to his 22pt,
    22/21 5/1 leaps ahead of 6/2*/1 in the rollout results. Not
    quite sure how to make sense of these results.

    XGID=aAaBBCBB--a-Aa-aacbbb-AA--:1:-1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O O O | | O O X X | +---+
    | O O | | O O | | 2 |
    | O | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | | |
    | | | X |
    | X | | X X X X |
    | X O X | | X X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 113 O: 154 X-O: 0-0
    Cube: 2, O own cube
    X to play 41

    1. Rollout¹ 6/2* 2/1 eq:+0.972
    Player: 69.56% (G:60.34% B:17.11%)
    Opponent: 30.44% (G:7.76% B:0.44%)
    Confidence: ±0.014 (+0.958..+0.986) - [100.0%]

    2. Rollout¹ 7/2* eq:+0.934 (-0.038)
    Player: 68.64% (G:57.62% B:19.76%)
    Opponent: 31.36% (G:9.38% B:0.60%)
    Confidence: ±0.013 (+0.921..+0.946) - [0.0%]

    3. Rollout¹ 22/21 5/1 eq:+0.887 (-0.085)
    Player: 67.89% (G:57.18% B:16.94%)
    Opponent: 32.11% (G:6.75% B:0.30%)
    Confidence: ±0.013 (+0.874..+0.899) - [0.0%]

    4. Rollout¹ 7/6 5/1 eq:+0.848 (-0.124)
    Player: 66.44% (G:56.38% B:18.07%)
    Opponent: 33.56% (G:7.93% B:0.37%)
    Confidence: ±0.013 (+0.835..+0.861) - [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=aAaBBCBB--a-Aa-aacbbb-B---:1:-1:1:41:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O O O | | O O X | +---+
    | O O | | O O X | | 2 |
    | O | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | | |
    | | | X |
    | X | | X X X X |
    | X O X | | X X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 112 O: 154 X-O: 0-0
    Cube: 2, O own cube
    X to play 41

    1. Rollout¹ 22/21 5/1 eq:+1.039
    Player: 71.25% (G:60.09% B:19.59%)
    Opponent: 28.75% (G:5.53% B:0.41%)
    Confidence: ±0.025 (+1.014..+1.064) - [100.0%]

    2. Rollout¹ 6/2* 2/1 eq:+0.970 (-0.069)
    Player: 69.71% (G:60.64% B:16.29%)
    Opponent: 30.29% (G:7.46% B:0.32%)
    Confidence: ±0.013 (+0.957..+0.984) - [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)