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  • Must leave a shot

    From Timothy Chow@21:1/5 to All on Wed Sep 7 08:54:10 2022
    XGID=--BabBEB----bB-a-c-bbbB---:1:1:1:53:0:0:0:0:10

    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 O O X |
    | X O | | O O O X |
    | O | | |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X | +---+
    | O X | | X X O X | | 2 |
    | O X | | X X O O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 154 X-O: 0-0
    Cube: 2, X own cube
    X to play 53

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Thu Sep 8 07:12:38 2022
    On Wednesday, September 7, 2022 at 1:54:12 PM UTC+1, Tim Chow wrote:
    XGID=--BabBEB----bB-a-c-bbbB---:1:1:1:53:0:0:0:0:10

    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 O O X |
    | X O | | O O O X |
    | O | | |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X | +---+
    | O X | | X X O X | | 2 |
    | O X | | X X O O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 154 X-O: 0-0
    Cube: 2, X own cube
    X to play 53

    We don't particularly want to be hit, but we need a play that pays off if the opponent rolls badly.
    13/5 (for example) isn't good because, if the opponent fails to hit, we don't have a strong enough upside.
    I'm going to say 6/3* 6/1 with a certain amount of confidence.
    I'll be surprised (but not amazed if I'm wrong. Our attack works well for the 16 rolls that don't hit back.
    And being hit isn't so terrible with three inner board points open and plenty of chances for contact in our favour.
    13/8 6/3* is a candidate but the midpoint is a fine asset to give up, and this play leaves three blots instead of two.
    6/3* 6/1.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Thu Sep 8 10:26:52 2022
    On 9/7/2022 8:54 AM, Timothy Chow wrote:
    XGID=--BabBEB----bB-a-c-bbbB---:1:1:1:53:0:0:0:0:10

    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  O  O  X       |
     | X           O    |   | O  O  O  X       |
     |             O    |   |                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   | X                |
     |                  |   | X                |
     |                  |   | X                | +---+
     | O              X |   | X  X  O     X    | | 2 |
     | O              X |   | X  X  O  O  X    | +---+
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 128  O: 154 X-O: 0-0
    Cube: 2, X own cube
    X to play 53


    7/2 7/4 doesn't leave a shot. X is ahead in the race, so safe play
    would be indicated. Hitting loose would make some sense if there were a reasonable five to play. I'll make the safe play.


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

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to ah....Clem on Thu Sep 8 07:54:13 2022
    On Thursday, September 8, 2022 at 3:26:53 PM UTC+1, ah....Clem wrote:
    On 9/7/2022 8:54 AM, Timothy Chow wrote:
    XGID=--BabBEB----bB-a-c-bbbB---:1:1:1:53:0:0:0:0:10

    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 O O X |
    | X O | | O O O X |
    | O | | |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X | +---+
    | O X | | X X O X | | 2 |
    | O X | | X X O O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 154 X-O: 0-0
    Cube: 2, X own cube
    X to play 53
    7/2 7/4 doesn't leave a shot.

    Agreed that it doesn't. But it has the slight disadvantage of being illegal.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Fri Sep 9 08:32:36 2022
    XGID=--BabBEB----bB-a-c-bbbB---:1:1:1:53:0:0:0:0:10

    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 O O X |
    | X O | | O O O X |
    | O | | |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X | +---+
    | O X | | X X O X | | 2 |
    | O X | | X X O O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 154 X-O: 0-0
    Cube: 2, X own cube
    X to play 53

    Congrats to Paul, who found the bot play 6/1 6/3*. If X hits with
    6/3*, then neither 7/2 nor 13/8 is more attractive than 6/1, so the
    principal alternative is 13/5. When you're forced to leave a shot
    in a mutual holding game, breaking the midpoint is often the lesser
    evil, but here, 6/1 6/3* unstacks the heavy 6pt, and as Paul says,
    it has a better upside if X is missed.

    1. Rollout¹ 6/1 6/3* eq:-0.203
    Player: 36.50% (G:13.03% B:0.33%)
    Opponent: 63.50% (G:18.89% B:0.91%)
    Confidence: ±0.010 (-0.214..-0.193) - [100.0%]

    2. Rollout¹ 7/2 6/3* eq:-0.266 (-0.062)
    Player: 34.42% (G:11.95% B:0.23%)
    Opponent: 65.58% (G:18.72% B:0.90%)
    Confidence: ±0.009 (-0.275..-0.257) - [0.0%]

    3. Rollout¹ 13/5 eq:-0.290 (-0.087)
    Player: 32.95% (G:9.85% B:0.34%)
    Opponent: 67.05% (G:15.34% B:0.66%)
    Confidence: ±0.009 (-0.299..-0.281) - [0.0%]

    4. Rollout¹ 13/8 6/3* eq:-0.294 (-0.091)
    Player: 34.01% (G:11.28% B:0.35%)
    Opponent: 65.99% (G:19.67% B:0.89%)
    Confidence: ±0.009 (-0.303..-0.286) - [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

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to peps...@gmail.com on Fri Sep 9 08:25:55 2022
    On 9/8/2022 10:54 AM, peps...@gmail.com wrote:
    Agreed that it doesn't. But it has the slight disadvantage of being illegal.

    Right. I sometimes write tricky subject lines, but I don't
    intentionally make blatantly false statements about which plays
    are legal.

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to ah....Clem on Fri Sep 9 12:37:59 2022
    On 9/8/2022 10:26 AM, ah....Clem wrote:
    On 9/7/2022 8:54 AM, Timothy Chow wrote:
    XGID=--BabBEB----bB-a-c-bbbB---:1:1:1:53:0:0:0:0:10

    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  O  O  X       |
      | X           O    |   | O  O  O  X       |
      |             O    |   |                  |
      |                  |   |                  |
      |                  |   |                  |
      |                  |BAR|                  |
      |                  |   | X                |
      |                  |   | X                |
      |                  |   | X                | +---+
      | O              X |   | X  X  O     X    | | 2 |
      | O              X |   | X  X  O  O  X    | +---+ >>   +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 128  O: 154 X-O: 0-0
    Cube: 2, X own cube
    X to play 53


    7/2 7/4 doesn't leave a shot.  X is ahead in the race, so safe play
    would be indicated.  Hitting loose would make some sense if there were a reasonable five to play.  I'll make the safe play.


    Boy, those Os on the four sure looked like Xs yesterday.

    I'd like to keep the midpoint, but exposing double direct shots when
    ahead in the race seems counterintuitive. So, 11/5 for me.



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

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Fri Sep 9 09:29:08 2022
    On Friday, September 9, 2022 at 1:25:55 PM UTC+1, Tim Chow wrote:
    On 9/8/2022 10:54 AM, peps...@gmail.com wrote:
    Agreed that it doesn't. But it has the slight disadvantage of being illegal.
    Right. I sometimes write tricky subject lines, but I don't
    intentionally make blatantly false statements about which plays
    are legal.

    ---
    Tim Chow

    But "must" isn't clearly defined.
    Wouldn't "must leave a shot" be a reasonable title (for you)
    if there were safe non-leaving-a-shot plays but they
    were too weak (in your opinion) to be worthy of consideration?

    "Must" doesn't always mean "legally must".

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to ah....Clem on Fri Sep 9 10:19:10 2022
    On Friday, September 9, 2022 at 5:37:59 PM UTC+1, ah....Clem wrote:
    On 9/8/2022 10:26 AM, ah....Clem wrote:
    On 9/7/2022 8:54 AM, Timothy Chow wrote:
    XGID=--BabBEB----bB-a-c-bbbB---:1:1:1:53:0:0:0:0:10

    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 O O X |
    | X O | | O O O X |
    | O | | |
    | | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X | +---+
    | O X | | X X O X | | 2 |
    | O X | | X X O O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 128 O: 154 X-O: 0-0
    Cube: 2, X own cube
    X to play 53


    7/2 7/4 doesn't leave a shot. X is ahead in the race, so safe play
    would be indicated. Hitting loose would make some sense if there were a reasonable five to play. I'll make the safe play.
    Boy, those Os on the four sure looked like Xs yesterday.

    I'd like to keep the midpoint, but exposing double direct shots when
    ahead in the race seems counterintuitive. So, 11/5 for me.
    --
    Ah....Clem
    The future is fun, the future is fair.

    Do you mean 13/5?

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to peps...@gmail.com on Sat Sep 10 08:08:42 2022
    On 9/9/2022 12:29 PM, peps...@gmail.com wrote:
    On Friday, September 9, 2022 at 1:25:55 PM UTC+1, Tim Chow wrote:
    On 9/8/2022 10:54 AM, peps...@gmail.com wrote:
    Agreed that it doesn't. But it has the slight disadvantage of being illegal.
    Right. I sometimes write tricky subject lines, but I don't
    intentionally make blatantly false statements about which plays
    are legal.

    ---
    Tim Chow

    But "must" isn't clearly defined.
    Wouldn't "must leave a shot" be a reasonable title (for you)
    if there were safe non-leaving-a-shot plays but they
    were too weak (in your opinion) to be worthy of consideration?

    "Must" doesn't always mean "legally must".

    Fair point. I intended "legally must" here, but you're right that the
    subject line doesn't quite explicitly assert that.

    ---
    Tim Chow

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