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  • Containment play

    From Timothy Chow@21:1/5 to All on Sat Nov 20 08:54:17 2021
    XGID=-a-B-BDB----bC---c-dbBba--:0:0:1:63:0:0:0:0:10

    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 X O O |
    | X O | | O O X O |
    | X O | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X | | X X X |
    | O X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 135 O: 116 X-O: 0-0
    Cube: 1
    X to play 63

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Tim Chow@21:1/5 to All on Mon Nov 22 07:53:21 2021
    XGID=-a-B-BDB----bC---c-dbBba--:0:0:1:63:0:0:0:0:10

    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 X O O |
    | X O | | O O X O |
    | X O | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X | | X X X |
    | O X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 135 O: 116 X-O: 0-0
    Cube: 1
    X to play 63

    Magriel's criteria suggest that X should be playing boldly
    to contain O's straggler. I tried 13/4 but 13/10 13/7 is a
    more effective priming play. See the variant to get a sense
    for how important it is that O has a blot in her board.

    1. Rollout¹ 13/10 13/7 eq:+0.217
    Player: 55.74% (G:12.81% B:0.55%)
    Opponent: 44.26% (G:9.63% B:0.29%)
    Confidence: ±0.012 (+0.204..+0.229) - [100.0%]

    2. Rollout¹ 13/4 eq:+0.105 (-0.112)
    Player: 53.41% (G:11.83% B:0.37%)
    Opponent: 46.59% (G:11.57% B:0.32%)
    Confidence: ±0.010 (+0.095..+0.115) - [0.0%]

    3. Rollout¹ 13/7 6/3 eq:+0.102 (-0.115)
    Player: 52.16% (G:9.87% B:0.28%)
    Opponent: 47.84% (G:8.40% B:0.28%)
    Confidence: ±0.011 (+0.091..+0.113) - [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=-a-B-BDB----cC---c-dbBb---:0:0:1:63:0:0:0:0:10

    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 X O |
    | X O | | O O X O |
    | X O | | O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | O | | X |
    | O X | | X X X |
    | O X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 135 O: 127 X-O: 0-0
    Cube: 1
    X to play 63

    1. Rollout¹ 13/10 13/7 eq:+0.186
    Player: 54.63% (G:12.52% B:0.31%)
    Opponent: 45.37% (G:8.49% B:0.30%)
    Confidence: ±0.010 (+0.176..+0.197) - [99.9%]

    2. Rollout¹ 13/7 6/3 eq:+0.163 (-0.024)
    Player: 53.90% (G:11.15% B:0.21%)
    Opponent: 46.10% (G:7.31% B:0.27%)
    Confidence: ±0.012 (+0.151..+0.174) - [0.1%]

    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 Timothy Chow@21:1/5 to All on Mon Jul 24 09:07:48 2023
    XGID=--aABBBBB---dB---B-cbb-c--:1:-1:1:42:0:0:0:0:10

    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 X | | O O O O | | 2 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | O | | |
    | O | | |
    | O X X | | X X X |
    | O X X | | X X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 123 O: 117 X-O: 0-0
    Cube: 2, O own cube
    X to play 42

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Mon Jul 24 13:20:53 2023
    On 7/24/2023 9:07 AM, Timothy Chow wrote:
    XGID=--aABBBBB---dB---B-cbb-c--:1:-1:1:42:0:0:0:0:10

    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           X    |   | O  O  O     O    | | 2 |
     |                  |   | O           O    | +---+
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     | O                |   |                  |
     | O                |   |                  |
     | O           X  X |   | X  X  X          |
     | O           X  X |   | X  X  X  X  O    |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 123  O: 117 X-O: 0-0
    Cube: 2, O own cube
    X to play 42

    Simply covering up by playing off the seven point is safe, but with the
    race deficit it looks weak.

    13/7 dupes aces and works really well the other 25 shakes so I'll play that.

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

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed Jul 26 08:52:35 2023
    XGID=--aABBBBB---dB---B-cbb-c--:1:-1:1:42:0:0:0:0:10

    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 X | | O O O O | | 2 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | O | | |
    | O | | |
    | O X X | | X X X |
    | O X X | | X X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 123 O: 117 X-O: 0-0
    Cube: 2, O own cube
    X to play 42

    Given O's strong board, I was leery of leaving a direct shot, but
    a five-prime with the opponent not at the edge is a huge asset.
    We have an advantage, but it's not so big that we need to play
    safe. Even if O had a stronger board, XG would still leave the 3pt
    slotted (see variant).

    As for 13/11 13/9 versus 13/7, it's definitely better to give
    yourself two ways to make a six-prime (either the front or the
    back).

    1. Rollout¹ 13/11 13/9 eq:+0.505
    Player: 76.41% (G:16.02% B:0.57%)
    Opponent: 23.59% (G:11.00% B:0.32%)
    Confidence: ±0.008 (+0.497..+0.514) - [100.0%]

    2. Rollout¹ 13/7 eq:+0.366 (-0.140)
    Player: 71.39% (G:15.56% B:0.61%)
    Opponent: 28.61% (G:11.62% B:0.24%)
    Confidence: ±0.008 (+0.358..+0.374) - [0.0%]

    3. Rollout¹ 7/5 7/3 eq:+0.349 (-0.156)
    Player: 68.17% (G:16.59% B:0.37%)
    Opponent: 31.83% (G:7.54% B:0.13%)
    Confidence: ±0.008 (+0.342..+0.357) - [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=--aABBBBB---dB---Bbbbbb---:1:-1:1:42:0:0:0:0:10

    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 O | +---+
    | X X O | | O O O O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | O | | |
    | O | | |
    | O X X | | X X X |
    | O X X | | X X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 123 O: 125 X-O: 0-0
    Cube: 2, O own cube
    X to play 42

    1. Rollout¹ 13/11 13/9 eq:+0.300
    Player: 69.51% (G:14.50% B:0.42%)
    Opponent: 30.49% (G:12.77% B:0.51%)
    Confidence: ±0.013 (+0.287..+0.313) - [99.8%]

    2. Rollout¹ 7/5 7/3 eq:+0.277 (-0.023)
    Player: 66.06% (G:14.80% B:0.23%)
    Opponent: 33.94% (G:8.15% B:0.26%)
    Confidence: ±0.008 (+0.269..+0.286) - [0.2%]

    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)