• Make the 5pt?

    From Tim Chow@21:1/5 to All on Tue Nov 23 13:48:09 2021
    XGID=-aabB-E-CA-Bb---a-bbbb-B--:1:-1:1:63:0:0:0:0:10

    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-+
    | O O | | O O O X | +---+
    | O | | O O O X | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | X | | X |
    | O X X | | X X O |
    | O X X X | | X X O O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 139 O: 170 X-O: 0-0
    Cube: 2, O own cube
    X to play 63

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From J R@21:1/5 to Tim Chow on Wed Nov 24 08:23:31 2021
    On Tuesday, November 23, 2021 at 4:48:10 PM UTC-5, Tim Chow wrote:
    XGID=-aabB-E-CA-Bb---a-bbbb-B--:1:-1:1:63:0:0:0:0:10

    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-+
    | O O | | O O O X | +---+
    | O | | O O O X | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | X | | X |
    | O X X | | X X O |
    | O X X X | | X X O O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 139 O: 170 X-O: 0-0
    Cube: 2, O own cube
    X to play 63

    ---
    Tim Chow

    Moving the blot on the 9pt back to the 10pt out of direct shot range if we were to make the 5pt would make this a far more interesting problem.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Tim Chow@21:1/5 to All on Thu Nov 25 14:09:30 2021
    XGID=-aabB-E-CA-Bb---a-bbbb-B--:1:-1:1:63:0:0:0:0:10

    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-+
    | O O | | O O O X | +---+
    | O | | O O O X | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | X | | X |
    | O X X | | X X O |
    | O X X X | | X X O O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 139 O: 170 X-O: 0-0
    Cube: 2, O own cube
    X to play 63

    X's biggest worry here is having checkers stuck behind
    O's prime. The awkward-looking 23/17 9/6 is the only play
    that XG thinks is worth considering.

    I had already rolled out the variant below before Stick
    suggested it. If X's blot were not in direct-shot range, then
    making the 5pt becomes a serious contender.

    1. Rollout¹ 23/17 9/6 eq:-0.530
    Player: 39.18% (G:13.42% B:0.71%)
    Opponent: 60.82% (G:18.32% B:0.83%)
    Confidence: ±0.013 (-0.543..-0.517) - [100.0%]

    2. Rollout¹ 11/5 8/5 eq:-0.626 (-0.096)
    Player: 35.25% (G:14.32% B:0.94%)
    Opponent: 64.75% (G:20.82% B:1.20%)
    Confidence: ±0.013 (-0.638..-0.613) - [0.0%]

    3. Rollout¹ 23/14 eq:-0.635 (-0.105)
    Player: 36.22% (G:12.61% B:0.94%)
    Opponent: 63.78% (G:22.05% B:1.26%)
    Confidence: ±0.013 (-0.648..-0.622) - [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=-aabB-E-C-ABb---a-bbbb-B--:1:-1:1:63:0:0:0:0:10

    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-+
    | O O | | O O O X | +---+
    | O | | O O O X | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | X | | X |
    | O X X | | X X O |
    | O X X X | | X X O O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 170 X-O: 0-0
    Cube: 2, O own cube
    X to play 63

    1. Rollout¹ 11/5 8/5 eq:-0.592
    Player: 36.37% (G:14.63% B:0.95%)
    Opponent: 63.63% (G:19.37% B:1.07%)
    Confidence: ±0.014 (-0.606..-0.578) - [65.3%]

    2. Rollout¹ 23/14 eq:-0.596 (-0.004)
    Player: 37.57% (G:13.12% B:0.79%)
    Opponent: 62.43% (G:20.61% B:1.14%)
    Confidence: ±0.015 (-0.611..-0.581) - [34.7%]

    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 Tue Mar 7 22:21:32 2023
    XGID=--aCC-B-BA--bB---dBbcab---:0:0:1:43:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O X | | O O O O |
    | X O X | | O O O |
    | O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | O X | | X X X |
    | O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 120 O: 118 X-O: 0-0
    Cube: 1
    X to play 43

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Timothy Chow on Wed Mar 8 06:55:25 2023
    On Tuesday, March 7, 2023 at 10:21:34 PM UTC-5, Timothy Chow wrote:
    XGID=--aCC-B-BA--bB---dBbcab---:0:0:1:43:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O X | | O O O O |
    | X O X | | O O O |
    | O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | O X | | X X X |
    | O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 120 O: 118 X-O: 0-0
    Cube: 1
    X to play 43

    ---
    Tim Chow

    The five point looks valuable enough to me in the games that can unfold that I would make it. There's about a 25% chance that O will hit and we won't hit back, but having the anchor is a nice advantage for X to fall back on. Hitting O's blot with 9/2
    would maybe be a little more disruptive to O near term, but having so much of the infield on the 2,3,4 points seems like a recipe for fizzling out. Bringing two checkers down from the midpoint would be my alternative to making the 5 point. Not an awful
    position, but those points will likely have to break up in the next roll or two, possibly leaving a shot and still no 5 point made.

    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sun Mar 12 08:47:49 2023
    XGID=--aCC-B-BA--bB---dBbcab---:0:0:1:43:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O X | | O O O O |
    | X O X | | O O O |
    | O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | O X | | X X X |
    | O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 120 O: 118 X-O: 0-0
    Cube: 1
    X to play 43

    Safe or bold? 13/10 13/9 gives O only 53 to hit. But O has a blot
    in her board, and XG favors the bold play of making the 5pt. See
    the variant, where O's board is stronger.

    1. Rollout¹ 9/5 8/5 eq:+0.207
    Player: 55.43% (G:15.27% B:0.28%)
    Opponent: 44.57% (G:11.68% B:0.40%)
    Confidence: ±0.011 (+0.197..+0.218) - [100.0%]

    2. Rollout¹ 13/10 13/9 eq:+0.098 (-0.109)
    Player: 52.34% (G:7.43% B:0.15%)
    Opponent: 47.66% (G:7.51% B:0.26%)
    Confidence: ±0.009 (+0.089..+0.108) - [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=--aCC-B-BA--bB---dBccb----:0:0:1:43:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O X | | O O O |
    | X O X | | O O O |
    | O | | O O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | O X | | X X X |
    | O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 120 O: 122 X-O: 0-0
    Cube: 1
    X to play 43

    1. Rollout¹ 13/10 13/9 eq:+0.154
    Player: 54.01% (G:7.60% B:0.16%)
    Opponent: 45.99% (G:7.21% B:0.27%)
    Confidence: ±0.009 (+0.145..+0.164) - [86.3%]

    2. Rollout¹ 9/5 8/5 eq:+0.145 (-0.009)
    Player: 54.16% (G:13.33% B:0.21%)
    Opponent: 45.84% (G:10.23% B:0.35%)
    Confidence: ±0.012 (+0.133..+0.158) - [13.7%]

    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 Timothy Chow@21:1/5 to All on Sun Mar 3 18:22:40 2024
    XGID=-a--b-EBC---bC---c-d-cB---:0:0:1:21:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O X |
    | X O | | O O X |
    | X O | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | X | | X |
    | O X X | | X O |
    | O X X | | X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 151 O: 152 X-O: 0-0
    Cube: 1
    X to play 21

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sun Mar 10 18:16:32 2024
    XGID=-a--b-EBC---bC---c-d-cB---:0:0:1:21:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O X |
    | X O | | O O X |
    | X O | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | X | | X |
    | O X X | | X O |
    | O X X | | X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 151 O: 152 X-O: 0-0
    Cube: 1
    X to play 21

    It's quite common for 7/5 6/5 to be the best way to play a 21, even if
    it volunteers a direct shot. Here, though, I balked, since 7/5 6/5
    volunteers a *double* direct shot. However, XG says it's a blunder to
    play anything else. In part, O's relatively weak offensive structure
    allows X to play boldly; see the variant for comparison.

    1. Rollout¹ 7/5 6/5 eq:+0.013
    Player: 50.87% (G:12.26% B:0.46%)
    Opponent: 49.13% (G:12.90% B:0.44%)
    Confidence: ±0.013 (0.000..+0.026) - [100.0%]

    2. Rollout¹ 6/3 eq:-0.074 (-0.087)
    Player: 48.69% (G:10.54% B:0.44%)
    Opponent: 51.31% (G:13.40% B:0.43%)
    Confidence: ±0.013 (-0.087..-0.061) - [0.0%]

    3. Rollout¹ 13/11 8/7 eq:-0.088 (-0.101)
    Player: 48.43% (G:10.32% B:0.42%)
    Opponent: 51.57% (G:12.71% B:0.44%)
    Confidence: ±0.013 (-0.101..-0.075) - [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--b-EBC---bC---c-cbbB---:0:0:1:21:0:0:0:0:10

    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 X |
    | X O | | O O O X |
    | X O | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | X | | X |
    | O X X | | X O |
    | O X X | | X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 151 O: 152 X-O: 0-0
    Cube: 1
    X to play 21

    1. Rollout¹ 7/5 6/5 eq:-0.383
    Player: 40.67% (G:9.11% B:0.38%)
    Opponent: 59.33% (G:15.49% B:0.63%)
    Confidence: ±0.007 (-0.391..-0.376) - [100.0%]

    2. Rollout¹ 13/11 8/7 eq:-0.408 (-0.024)
    Player: 40.17% (G:7.81% B:0.31%)
    Opponent: 59.83% (G:14.16% B:0.55%)
    Confidence: ±0.007 (-0.415..-0.400) - [0.0%]

    3. Rollout² 6/3 eq:-0.432 (-0.049)
    Player: 39.51% (G:7.73% B:0.29%)
    Opponent: 60.49% (G:14.47% B:0.55%)
    Confidence: ±0.013 (-0.445..-0.419) - [0.0%]

    ¹ 5184 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    ² 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)