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  • Snake eyes

    From Tim Chow@21:1/5 to All on Sat Nov 27 10:47:12 2021
    XGID=--BBbDC--B---------cbbbdB-:1:1:1:11:0:0:0:0:10

    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-+
    | | | O O O O O X |
    | | | O O O O O X |
    | | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X X | +---+
    | X | | X X O X X | | 2 |
    | X | | X X O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 92 X-O: 0-0
    Cube: 2, X own cube
    X to play 11

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Tue Nov 30 09:38:27 2021
    XGID=--BBbDC--B---------cbbbdB-:1:1:1:11:0:0:0:0:10

    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-+
    | | | O O O O O X |
    | | | O O O O O X |
    | | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X X | +---+
    | X | | X X O X X | | 2 |
    | X | | X X O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 92 X-O: 0-0
    Cube: 2, X own cube
    X to play 11

    Behind in the race, I wanted to keep my 9pt to block in O's back
    checkers as much as possible, and I played 3/1(2). I'm still not
    sure why XG thinks 3/1(2) is so bad. I found a variant which should
    give some insight but I'm still not sure what the insight is.

    1. Rollout¹ 9/8(2) 2/1(2) eq:-0.350
    Player: 32.18% (G:6.25% B:0.18%)
    Opponent: 67.82% (G:16.15% B:0.73%)
    Confidence: ±0.006 (-0.356..-0.344) - [87.6%]

    2. Rollout¹ 9/7(2) eq:-0.355 (-0.005)
    Player: 32.00% (G:6.23% B:0.20%)
    Opponent: 68.00% (G:16.42% B:0.86%)
    Confidence: ±0.006 (-0.361..-0.349) - [12.4%]

    3. Rollout¹ 9/8(2) 3/1 eq:-0.455 (-0.105)
    Player: 29.19% (G:5.42% B:0.16%)
    Opponent: 70.81% (G:18.41% B:1.08%)
    Confidence: ±0.007 (-0.462..-0.449) - [0.0%]

    4. Rollout¹ 3/1(2) eq:-0.496 (-0.146)
    Player: 27.61% (G:4.92% B:0.13%)
    Opponent: 72.39% (G:18.18% B:0.89%)
    Confidence: ±0.006 (-0.502..-0.490) - [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

    -------
    Variant
    -------

    XGID=--BBbDC--B-------a-bbbbdB-:1:1:1:11:0:0:0:0:10

    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-+
    | O | | O O O O O X |
    | | | O O O O O X |
    | | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X X | +---+
    | X | | X X O X X | | 2 |
    | X | | X X O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 94 X-O: 0-0
    Cube: 2, X own cube
    X to play 11

    1. Rollout¹ 9/7(2) eq:-0.399
    Player: 30.49% (G:5.99% B:0.21%)
    Opponent: 69.51% (G:16.37% B:0.86%)
    Confidence: ±0.006 (-0.405..-0.393) - [100.0%]

    2. Rollout¹ 3/1(2) eq:-0.422 (-0.023)
    Player: 29.69% (G:5.85% B:0.19%)
    Opponent: 70.31% (G:16.87% B:0.70%)
    Confidence: ±0.007 (-0.429..-0.415) - [0.0%]

    3. Rollout¹ 9/8(2) 2/1(2) eq:-0.428 (-0.029)
    Player: 29.22% (G:5.89% B:0.19%)
    Opponent: 70.78% (G:16.38% B:0.70%)
    Confidence: ±0.006 (-0.434..-0.422) - [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 J R@21:1/5 to Tim Chow on Tue Nov 30 15:26:25 2021
    On Tuesday, November 30, 2021 at 9:38:31 AM UTC-5, Tim Chow wrote:
    XGID=--BBbDC--B---------cbbbdB-:1:1:1:11:0:0:0:0:10

    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-+
    | | | O O O O O X |
    | | | O O O O O X |
    | | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X X | +---+
    | X | | X X O X X | | 2 |
    | X | | X X O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 92 X-O: 0-0
    Cube: 2, X own cube
    X to play 11
    Behind in the race, I wanted to keep my 9pt to block in O's back
    checkers as much as possible, and I played 3/1(2). I'm still not
    sure why XG thinks 3/1(2) is so bad. I found a variant which should
    give some insight but I'm still not sure what the insight is.

    1. Rollout¹ 9/8(2) 2/1(2) eq:-0.350
    Player: 32.18% (G:6.25% B:0.18%)
    Opponent: 67.82% (G:16.15% B:0.73%)
    Confidence: ±0.006 (-0.356..-0.344) - [87.6%]

    2. Rollout¹ 9/7(2) eq:-0.355 (-0.005)
    Player: 32.00% (G:6.23% B:0.20%)
    Opponent: 68.00% (G:16.42% B:0.86%)
    Confidence: ±0.006 (-0.361..-0.349) - [12.4%]

    3. Rollout¹ 9/8(2) 3/1 eq:-0.455 (-0.105)
    Player: 29.19% (G:5.42% B:0.16%)
    Opponent: 70.81% (G:18.41% B:1.08%)
    Confidence: ±0.007 (-0.462..-0.449) - [0.0%]

    4. Rollout¹ 3/1(2) eq:-0.496 (-0.146)
    Player: 27.61% (G:4.92% B:0.13%)
    Opponent: 72.39% (G:18.18% B:0.89%)
    Confidence: ±0.006 (-0.502..-0.490) - [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

    -------
    Variant
    -------

    XGID=--BBbDC--B-------a-bbbbdB-:1:1:1:11:0:0:0:0:10
    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-+
    | O | | O O O O O X |
    | | | O O O O O X |
    | | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X X | +---+
    | X | | X X O X X | | 2 |
    | X | | X X O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 114 O: 94 X-O: 0-0
    Cube: 2, X own cube
    X to play 11
    1. Rollout¹ 9/7(2) eq:-0.399
    Player: 30.49% (G:5.99% B:0.21%)
    Opponent: 69.51% (G:16.37% B:0.86%)
    Confidence: ±0.006 (-0.405..-0.393) - [100.0%]

    2. Rollout¹ 3/1(2) eq:-0.422 (-0.023)
    Player: 29.69% (G:5.85% B:0.19%)
    Opponent: 70.31% (G:16.87% B:0.70%)
    Confidence: ±0.007 (-0.429..-0.415) - [0.0%]

    3. Rollout¹ 9/8(2) 2/1(2) eq:-0.428 (-0.029)
    Player: 29.22% (G:5.89% B:0.19%)
    Opponent: 70.78% (G:16.38% B:0.70%)
    Confidence: ±0.006 (-0.434..-0.422) - [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

    You want to force the opponent to play his bad fours by breaking his board thus 8(2) and stop. There are no bad fives in that respect if you stay back.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to J R on Wed Dec 1 08:31:36 2021
    On 11/30/2021 6:26 PM, J R wrote:
    You want to force the opponent to play his bad fours by breaking his board thus 8(2) and stop. There are no bad fives in that respect if you stay back.

    Good observation about the bad fours, but according to the
    rollout, 9/7(2) is just about as good as 9/8(2), so I don't
    think fours can be the whole story?

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Philippe Michel@21:1/5 to Timothy Chow on Wed Dec 1 22:23:28 2021
    On 2021-12-01, Timothy Chow <tchow12000@yahoo.com> wrote:
    On 11/30/2021 6:26 PM, J R wrote:
    You want to force the opponent to play his bad fours by breaking his board thus 8(2) and stop. There are no bad fives in that respect if you stay back.

    Good observation about the bad fours, but according to the
    rollout, 9/7(2) is just about as good as 9/8(2), so I don't
    think fours can be the whole story?

    After 9/7(2), 33 is very, very bad and 32 is not great either. Probably
    root numbers in general are the whole story.

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