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  • 33 is usually luckier than this

    From Timothy Chow@21:1/5 to All on Mon May 15 08:57:59 2023
    XGID=---b-BDBB-A-bB-a-b-cbc--B-:0:0:1:33:0:0:0:0:10

    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 148 O: 136 X-O: 0-0
    Cube: 1
    X to play 33

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Timothy Chow on Mon May 15 07:39:45 2023
    On Monday, May 15, 2023 at 1:59:34 PM UTC+1, Timothy Chow wrote:
    XGID=---b-BDBB-A-bB-a-b-cbc--B-:0:0:1:33:0:0:0:0:10

    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 148 O: 136 X-O: 0-0
    Cube: 1
    X to play 33

    I think I know this one (but of course very far from sure).
    The point is that we shouldn't fall so much in love with our prime
    that we maintain it at the expense of our midpoint.
    Leaving the midpoint would be a big mistake here, as it gives the
    opponent free rein to use her own midpoint checkers to obtain
    a crushing prime against our acepoint.

    My play is 7/4(2) 8/5(2) which looks clearly best among the midpoint-preserving plays. 8/5(2) is a positional concession but the upside is that we have some good
    attacking possibilities if the opponent is forced to leave our 3 point with one checker.

    8/4(2) 7/5(2)

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to peps...@gmail.com on Tue May 16 13:46:37 2023
    On Monday, May 15, 2023 at 10:39:47 AM UTC-4, peps...@gmail.com wrote:
    On Monday, May 15, 2023 at 1:59:34 PM UTC+1, Timothy Chow wrote:
    XGID=---b-BDBB-A-bB-a-b-cbc--B-:0:0:1:33:0:0:0:0:10

    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 148 O: 136 X-O: 0-0
    Cube: 1
    X to play 33
    I think I know this one (but of course very far from sure).
    The point is that we shouldn't fall so much in love with our prime
    that we maintain it at the expense of our midpoint.
    Leaving the midpoint would be a big mistake here, as it gives the
    opponent free rein to use her own midpoint checkers to obtain
    a crushing prime against our acepoint.

    My play is 7/4(2) 8/5(2) which looks clearly best among the midpoint-preserving
    plays. 8/5(2) is a positional concession but the upside is that we have some good
    attacking possibilities if the opponent is forced to leave our 3 point with one checker.

    8/4(2) 7/5(2)

    Paul

    If you're going to play 7/4(2) wouldn't 10/4 with the last two threes be far better as far as keeping the midpoint plays go? It picks up the blot, it keeps the prime, etc...

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Stick Rice on Tue May 16 14:47:51 2023
    On Tuesday, May 16, 2023 at 9:46:38 PM UTC+1, Stick Rice wrote:
    On Monday, May 15, 2023 at 10:39:47 AM UTC-4, peps...@gmail.com wrote:
    On Monday, May 15, 2023 at 1:59:34 PM UTC+1, Timothy Chow wrote:
    XGID=---b-BDBB-A-bB-a-b-cbc--B-:0:0:1:33:0:0:0:0:10

    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 148 O: 136 X-O: 0-0
    Cube: 1
    X to play 33
    I think I know this one (but of course very far from sure).
    The point is that we shouldn't fall so much in love with our prime
    that we maintain it at the expense of our midpoint.
    Leaving the midpoint would be a big mistake here, as it gives the
    opponent free rein to use her own midpoint checkers to obtain
    a crushing prime against our acepoint.

    My play is 7/4(2) 8/5(2) which looks clearly best among the midpoint-preserving
    plays. 8/5(2) is a positional concession but the upside is that we have some good
    attacking possibilities if the opponent is forced to leave our 3 point with one checker.

    8/4(2) 7/5(2)

    Paul
    If you're going to play 7/4(2) wouldn't 10/4 with the last two threes be far better as far as keeping the midpoint plays go? It picks up the blot, it keeps the prime, etc...

    Stick
    Yes, you're right. I missed that. When am I going to get one of these problems right???

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed May 17 08:13:08 2023
    XGID=---b-BDBB-A-bB-a-b-cbc--B-:0:0:1:33:0:0:0:0:10

    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 148 O: 136 X-O: 0-0
    Cube: 1
    X to play 33

    I didn't consider volunteering a shot by slotting the front of the
    prime, since I didn't think my position was that desperate yet. For comparison, see the variant, in which X's anchor is further forward.
    Although XG still favors 13/10 13/4 in the variant, it thinks the
    decision is much closer.

    1. Rollout¹ 13/10 13/4 eq:-0.480
    Player: 38.99% (G:10.19% B:0.65%)
    Opponent: 61.01% (G:20.98% B:1.52%)
    Confidence: ±0.014 (-0.494..-0.466) - [100.0%]

    2. Rollout¹ 13/7(2) eq:-0.543 (-0.063)
    Player: 37.04% (G:9.09% B:0.46%)
    Opponent: 62.96% (G:20.73% B:1.02%)
    Confidence: ±0.013 (-0.555..-0.530) - [0.0%]

    3. Rollout¹ 10/4 7/4(2) eq:-0.553 (-0.073)
    Player: 36.88% (G:9.21% B:0.34%)
    Opponent: 63.12% (G:20.53% B:0.83%)
    Confidence: ±0.011 (-0.564..-0.542) - [0.0%]

    4. Rollout¹ 13/10(2) 7/4(2) eq:-0.634 (-0.154)
    Player: 34.94% (G:8.56% B:0.41%)
    Opponent: 65.06% (G:20.50% B:0.76%)
    Confidence: ±0.014 (-0.647..-0.620) - [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=---b-BDBB-A-bB-a-b-cbcB---:0:0:1:33:0:0:0:0:10

    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 144 O: 136 X-O: 0-0
    Cube: 1
    X to play 33

    1. Rollout¹ 13/10 13/4 eq:-0.022
    Player: 49.41% (G:12.02% B:0.49%)
    Opponent: 50.59% (G:12.50% B:0.50%)
    Confidence: ±0.009 (-0.032..-0.013) - [99.5%]

    2. Rollout¹ 10/4 7/4(2) eq:-0.039 (-0.017)
    Player: 48.95% (G:11.14% B:0.38%)
    Opponent: 51.05% (G:11.41% B:0.41%)
    Confidence: ±0.008 (-0.047..-0.031) - [0.4%]

    3. Rollout¹ 13/7(2) eq:-0.045 (-0.023)
    Player: 48.75% (G:11.42% B:0.45%)
    Opponent: 51.25% (G:11.32% B:0.43%)
    Confidence: ±0.010 (-0.055..-0.035) - [0.0%]

    4. Rollout¹ 13/10(2) 7/4(2) eq:-0.059 (-0.037)
    Player: 48.41% (G:10.15% B:0.39%)
    Opponent: 51.59% (G:9.84% B:0.38%)
    Confidence: ±0.008 (-0.067..-0.051) - [0.0%]

    ¹ 2592 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 pepstein5@gmail.com@21:1/5 to Timothy Chow on Wed May 17 08:26:36 2023
    On Wednesday, May 17, 2023 at 1:15:00 PM UTC+1, Timothy Chow wrote:
    XGID=---b-BDBB-A-bB-a-b-cbc--B-:0:0:1:33:0:0:0:0:10

    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 148 O: 136 X-O: 0-0
    Cube: 1
    X to play 33
    I didn't consider volunteering a shot by slotting the front of the
    prime, since I didn't think my position was that desperate yet. For comparison, see the variant, in which X's anchor is further forward. Although XG still favors 13/10 13/4 in the variant, it thinks the
    decision is much closer.

    1. Rollout¹ 13/10 13/4 eq:-0.480
    Player: 38.99% (G:10.19% B:0.65%)
    Opponent: 61.01% (G:20.98% B:1.52%)
    Confidence: ±0.014 (-0.494..-0.466) - [100.0%]

    2. Rollout¹ 13/7(2) eq:-0.543 (-0.063)
    Player: 37.04% (G:9.09% B:0.46%)
    Opponent: 62.96% (G:20.73% B:1.02%)
    Confidence: ±0.013 (-0.555..-0.530) - [0.0%]

    3. Rollout¹ 10/4 7/4(2) eq:-0.553 (-0.073)
    Player: 36.88% (G:9.21% B:0.34%)
    Opponent: 63.12% (G:20.53% B:0.83%)
    Confidence: ±0.011 (-0.564..-0.542) - [0.0%]

    4. Rollout¹ 13/10(2) 7/4(2) eq:-0.634 (-0.154)
    Player: 34.94% (G:8.56% B:0.41%)
    Opponent: 65.06% (G:20.50% B:0.76%)
    Confidence: ±0.014 (-0.647..-0.620) - [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=---b-BDBB-A-bB-a-b-cbcB---:0:0:1:33:0:0:0:0:10
    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 |
    | X O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 144 O: 136 X-O: 0-0
    Cube: 1
    X to play 33
    1. Rollout¹ 13/10 13/4 eq:-0.022
    Player: 49.41% (G:12.02% B:0.49%)
    Opponent: 50.59% (G:12.50% B:0.50%)
    Confidence: ±0.009 (-0.032..-0.013) - [99.5%]

    2. Rollout¹ 10/4 7/4(2) eq:-0.039 (-0.017)
    Player: 48.95% (G:11.14% B:0.38%)
    Opponent: 51.05% (G:11.41% B:0.41%)
    Confidence: ±0.008 (-0.047..-0.031) - [0.4%]

    3. Rollout¹ 13/7(2) eq:-0.045 (-0.023)
    Player: 48.75% (G:11.42% B:0.45%)
    Opponent: 51.25% (G:11.32% B:0.43%)
    Confidence: ±0.010 (-0.055..-0.035) - [0.0%]

    4. Rollout¹ 13/10(2) 7/4(2) eq:-0.059 (-0.037)
    Player: 48.41% (G:10.15% B:0.39%)
    Opponent: 51.59% (G:9.84% B:0.38%)
    Confidence: ±0.008 (-0.067..-0.051) - [0.0%]

    ¹ 2592 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

    If we realise that keeping the midpoint is wrong, then there are duplication considerations. If we break the midpoint then the opponent has excellent aces to
    prepare to strengthen their prime even further.
    So conceding a shot on the ace point is such a big concession as it appears.

    Paul

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