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  • 5pt problem 4

    From Timothy Chow@21:1/5 to All on Sat Oct 29 08:12:52 2022
    XGID=----b-FCC--Ad----aBca-bb--:0:0:1:61:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O |
    | X | | O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | 6 |
    | O | | X |
    | O X X | | X |
    | O X X | | X O |
    | O X X X | | X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 135 X-O: 0-0
    Cube: 1
    X to play 61

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Sat Oct 29 13:53:16 2022
    On Saturday, October 29, 2022 at 1:12:55 PM UTC+1, Tim Chow wrote:
    XGID=----b-FCC--Ad----aBca-bb--:0:0:1:61:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O |
    | X | | O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | 6 |
    | O | | X |
    | O X X | | X |
    | O X X | | X O |
    | O X X X | | X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 135 X-O: 0-0
    Cube: 1
    X to play 61

    ---
    Tim Chow

    I'll make the 5 point here for sure.
    The problem with hitting is that the opponent has a lot of dangerous return hits,
    and also the hit is hardly devastating -- hitting doesn't give a good risk/reward
    ratio. It's a bit like eating a cheese and pickle sandwich where the filling is 90%
    pickles and only 10% cheese. Yes, the 10% of bites with succulent cheddar cheese
    will be enjoyable but the pickle factor dominates.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sun Oct 30 08:49:43 2022
    XGID=--aaC-C-C-B-cB---c-cbBb---:0:0:1:31:0:0:0:0:10

    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 O |
    | X O | | O O X O |
    | O | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | O X | | X X |
    | O X X | | X X |
    | O X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 142 O: 142 X-O: 0-0
    Cube: 1
    X to play 31

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to Timothy Chow on Sun Oct 30 08:50:29 2022
    Sorry, the subject line should have been, "5pt problem 5."

    On 10/30/2022 8:49 AM, Timothy Chow wrote:
    XGID=--aaC-C-C-B-cB---c-cbBb---:0:0:1:31:0:0:0:0:10

    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  O       |
     | X           O    |   | O  O  X  O       |
     |             O    |   | O                |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     | O           X    |   | X     X          |
     | O     X     X    |   | X     X          |
     | O     X     X    |   | X     X  O  O    |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 142  O: 142 X-O: 0-0
    Cube: 1
    X to play 31

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sun Oct 30 17:55:02 2022
    On 10/29/2022 8:12 AM, Timothy Chow wrote:
    XGID=----b-FCC--Ad----aBca-bb--:0:0:1:61:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     |             O  X |   | O  O     O  O    |
     |                X |   | O        O  O    |
     |                  |   | O                |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   | 6                |
     | O                |   | X                |
     | O           X  X |   | X                |
     | O           X  X |   | X     O          |
     | O  X        X  X |   | X     O          |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 128  O: 135 X-O: 0-0
    Cube: 1
    X to play 61


    Making the five unstacks the bloated six point, exposes no shots,
    safeties a blot, and ... well... makes the five point.

    Hitting gains a lot in the race while running off the anchor with tempo
    is certainly worth something.

    Not sure, so I'll make the five, QF be damned. Perhaps someone could
    explain why it's "obvious" to hit instead. O's better board and X's
    lead in the race point to a safe play.

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

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Mon Oct 31 07:49:41 2022
    XGID=----b-FCC--Ad----aBca-bb--:0:0:1:61:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O |
    | X | | O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | 6 |
    | O | | X |
    | O X X | | X |
    | O X X | | X O |
    | O X X X | | X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 135 X-O: 0-0
    Cube: 1
    X to play 61

    As ah_clem says, O's better board and X's lead in the pip count would
    seem to suggest playing safe with 11/5 6/5. However, in a sense, this
    is a pay-now-or-later decision---one that badgolferman might appreciate,
    since he recognizes that breaking the bar-point anchor safely can be a headache. O's board rates to get stronger over the next couple of rolls,
    and 18/17*/11 leaves only one blot for O to attack.

    In the variant, I have strengthened O's board, and the two plays are
    virtually tied in the rollout.

    1. Rollout¹ 18/17* 17/11 eq:+0.492
    Player: 62.99% (G:12.36% B:0.50%)
    Opponent: 37.01% (G:8.52% B:0.20%)
    Confidence: ±0.011 (+0.481..+0.504) - [100.0%]

    2. Rollout¹ 11/5 6/5 eq:+0.400 (-0.092)
    Player: 61.51% (G:7.99% B:0.25%)
    Opponent: 38.49% (G:4.93% B:0.15%)
    Confidence: ±0.010 (+0.390..+0.410) - [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-FCC--Ad----aBb--bbb-:0:0:1:61:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O |
    | X | | O O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | 6 |
    | O | | X |
    | O X X | | X |
    | O X X | | X O |
    | O X X X | | X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 126 X-O: 0-0
    Cube: 1
    X to play 61

    1. Rollout¹ 11/5 6/5 eq:+0.368
    Player: 60.55% (G:9.09% B:0.29%)
    Opponent: 39.45% (G:5.62% B:0.13%)
    Confidence: ±0.011 (+0.358..+0.379) - [91.7%]

    2. Rollout¹ 18/17* 17/11 eq:+0.355 (-0.013)
    Player: 60.99% (G:9.63% B:0.40%)
    Opponent: 39.01% (G:10.20% B:0.16%)
    Confidence: ±0.015 (+0.340..+0.370) - [8.3%]

    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)