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  • 4pt vs 7pt 8

    From Timothy Chow@21:1/5 to All on Sun Jul 9 09:18:42 2023
    Ah...clem said that he wanted to see more "4pt vs 7pt" problems,
    so this week I'll post some more.

    XGID=---b-BE-D---cC---c-cac-A--:0:0:1:11:0:0:0:0:10

    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 |
    | X O | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | X | | X |
    | O X | | X |
    | O X | | X X O |
    | O X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 134 O: 142 X-O: 0-0
    Cube: 1
    X to play 11

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sun Jul 9 10:18:28 2023
    On 7/9/2023 9:18 AM, Timothy Chow wrote:
    Ah...clem said that he wanted to see more "4pt vs 7pt" problems,
    so this week I'll post some more.

    XGID=---b-BE-D---cC---c-cac-A--:0:0:1:11:0:0:0:0:10

    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          |
     | X           O    |   | O     O          |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   | X                |
     |             X    |   | X                |
     | O           X    |   | X                |
     | O           X    |   | X  X     O       |
     | O           X    |   | X  X     O       |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 134  O: 142 X-O: 0-0
    Cube: 1
    X to play 11


    The bar point does a better job of blocking but making the four leaves
    spares on the 8 & 6 vs a big stack on the six with the other points
    stripped. X may pick up the blot on the 20 and making "the rack" will be
    more advantageous if he does.

    So, I make the four here.
    --
    Ah....Clem
    The future is fun, the future is fair.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Renan Moritz@21:1/5 to ah....Clem on Sun Jul 9 09:56:41 2023
    On Sunday, July 9, 2023 at 11:18:29 AM UTC-3, ah....Clem wrote:
    On 7/9/2023 9:18 AM, Timothy Chow wrote:
    Ah...clem said that he wanted to see more "4pt vs 7pt" problems,
    so this week I'll post some more.

    XGID=---b-BE-D---cC---c-cac-A--:0:0:1:11:0:0:0:0:10

    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 |
    | X O | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | X | | X |
    | O X | | X |
    | O X | | X X O |
    | O X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 134 O: 142 X-O: 0-0
    Cube: 1
    X to play 11
    The bar point does a better job of blocking but making the four leaves spares on the 8 & 6 vs a big stack on the six with the other points stripped. X may pick up the blot on the 20 and making "the rack" will be more advantageous if he does.

    So, I make the four here.
    --
    Ah....Clem
    The future is fun, the future is fair.

    These problems are not much of a problem for me because as a rule I make the 4th point and that is it
    In this case, however, the ugly stack on the 8th point and the usefulness of advancing the last checker makes me opt for the bar Thus:
    23/22, 8/7(2), 6/5
    Regards,

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to ah....Clem on Mon Jul 10 10:58:38 2023
    On 7/9/2023 10:18 AM, ah....Clem wrote:
    On 7/9/2023 9:18 AM, Timothy Chow wrote:
    Ah...clem said that he wanted to see more "4pt vs 7pt" problems,
    so this week I'll post some more.

    XGID=---b-BE-D---cC---c-cac-A--:0:0:1:11:0:0:0:0:10

    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          | >>   | X           O    |   | O     O          | >>   |                  |   |                  |
      |                  |   |                  |
      |                  |BAR|                  |
      |                  |   | X                |
      |             X    |   | X                |
      | O           X    |   | X                |
      | O           X    |   | X  X     O       |
      | O           X    |   | X  X     O       |
      +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 134  O: 142 X-O: 0-0
    Cube: 1
    X to play 11


    The bar point does a better job of blocking but making the four leaves
    spares on the 8 & 6 vs a big stack on the six with the other points
    stripped. X may pick up the blot on the 20 and making "the rack" will be
    more advantageous if he does.

    So, I make the four here.

    Oops. After making the bar point X still has two aces to play. The
    solid four prime looks better than the broken one, and X can use the
    other two aces to unstack the six point and move the runner up to where
    it can see daylight.

    So, I'll make the bar point with 23/22 8/7(2) 6/5.



    --
    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 Tue Jul 11 09:18:33 2023
    XGID=---b-BE-D---cC---c-cac-A--:0:0:1:11:0:0:0:0:10

    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 |
    | X O | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | X | | X |
    | O X | | X |
    | O X | | X X O |
    | O X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 134 O: 142 X-O: 0-0
    Cube: 1
    X to play 11

    In my previous series, I suggested that the 4pt is better for attacking
    and the bar point is better for priming. But here, neither attacking
    nor priming jumps out as the superior game plan. What tips the scales
    is that X certainly wants to escape his straggler, and so 23/22 is a
    valuable ace.

    In the variant, 23/22 is not an option, and the rollout indicates a
    dead heat.

    1. Rollout¹ 23/22 8/7(2) 6/5 eq:+0.325
    Player: 59.23% (G:10.72% B:0.47%)
    Opponent: 40.77% (G:10.18% B:0.23%)
    Confidence: ±0.012 (+0.313..+0.338) - [100.0%]

    2. Rollout¹ 8/7(2) 6/5(2) eq:+0.220 (-0.105)
    Player: 56.31% (G:11.14% B:0.45%)
    Opponent: 43.69% (G:11.06% B:0.29%)
    Confidence: ±0.013 (+0.206..+0.233) - [0.0%]

    3. Rollout¹ 6/4(2) eq:+0.208 (-0.117)
    Player: 55.77% (G:11.11% B:0.45%)
    Opponent: 44.23% (G:10.19% B:0.25%)
    Confidence: ±0.014 (+0.193..+0.222) - [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-BE-D---cC---c-cacA---:0:0:1:11:0:0:0:0:10

    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 |
    | X O | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | X | | X |
    | O X | | X |
    | O X | | X X O |
    | O X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 133 O: 142 X-O: 0-0
    Cube: 1
    X to play 11

    1. Rollout¹ 8/7(2) 6/5(2) eq:+0.301
    Player: 58.56% (G:10.61% B:0.45%)
    Opponent: 41.44% (G:10.69% B:0.27%)
    Confidence: ±0.006 (+0.295..+0.307) - [60.4%]

    2. Rollout¹ 6/4(2) eq:+0.300 (-0.001)
    Player: 58.38% (G:10.50% B:0.43%)
    Opponent: 41.62% (G:9.43% B:0.22%)
    Confidence: ±0.006 (+0.294..+0.306) - [39.6%]

    ¹ 5184 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)