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  • Another noncontact cube action

    From Timothy Chow@21:1/5 to All on Thu Jul 21 08:57:07 2022
    XGID=---CCCE----Aa---a-ad-ec---:0:0:1:00:0:0:0:0:10

    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 |
    | | | O O O |
    | | | O O O |
    | | | O O |
    | | | O |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X X X |
    | | | X X X X |
    | O X | | X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 77 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Thu Jul 21 16:44:27 2022
    On 7/21/2022 8:57 AM, Timothy Chow wrote:
    XGID=---CCCE----Aa---a-ad-ec---:0:0:1:00:0:0:0:0:10

    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       |
     |                  |   | O     O  O       |
     |                  |   | O     O  O       |
     |                  |   | O     O          |
     |                  |   |       O          |
     |                  |BAR|                  |
     |                  |   | X                |
     |                  |   | X                |
     |                  |   | X  X  X  X       |
     |                  |   | X  X  X  X       |
     | O  X             |   | X  X  X  X       |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 77  O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    Adj pipcount is 78 - 86, POLT is 8, so looks like a close take and a
    very clear cube. Won't be surprised if it's a close pass.


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

    --- SoupGate-Win32 v1.05
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  • From Timothy Chow@21:1/5 to All on Sat Jul 23 08:47:09 2022
    XGID=---CCCE----Aa---a-ad-ec---:0:0:1:00:0:0:0:0:10

    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 |
    | | | O O O |
    | | | O O O |
    | | | O O |
    | | | O |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X X X |
    | | | X X X X |
    | O X | | X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 77 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    This time the Keith count says it's a clear ND, which is wrong
    but not wildly wrong. I think it's because O's distribution has
    some flaws that the Keith count fails to account for. Does Isight
    have a different verdict? I have the vague impression that Isight
    is designed for positions where all the checkers are already in the
    home board, but maybe that impression is wrong.


    Analyzed in Rollout
    No double
    Player Winning Chances: 73.48% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.52% (G:0.00% B:0.00%)
    Double/Take
    Player Winning Chances: 73.47% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.53% (G:0.00% B:0.00%)

    Cubeful Equities:
    No double: +0.726 (-0.041)
    Double/Take: +0.767
    Double/Pass: +1.000 (+0.233)

    Best Cube action: Double / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 4-ply, cube decisions: XG Roller+
    Search interval: Huge
    Confidence No Double: ± 0.002 (+0.724..+0.728)
    Confidence Double: ± 0.003 (+0.764..+0.770)

    eXtreme Gammon Version: 2.19.207.pre-release

    ---
    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 Jul 23 16:28:00 2022
    On Saturday, July 23, 2022 at 1:47:14 PM UTC+1, Tim Chow wrote:
    XGID=---CCCE----Aa---a-ad-ec---:0:0:1:00:0:0:0:0:10

    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 |
    | | | O O O |
    | | | O O O |
    | | | O O |
    | | | O |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X X X |
    | | | X X X X |
    | O X | | X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 77 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action
    This time the Keith count says it's a clear ND, which is wrong
    but not wildly wrong. I think it's because O's distribution has
    some flaws that the Keith count fails to account for. Does Isight
    have a different verdict? I have the vague impression that Isight
    is designed for positions where all the checkers are already in the
    home board, but maybe that impression is wrong.


    Analyzed in Rollout
    No double
    Player Winning Chances: 73.48% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.52% (G:0.00% B:0.00%)
    Double/Take
    Player Winning Chances: 73.47% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.53% (G:0.00% B:0.00%)

    Cubeful Equities:
    No double: +0.726 (-0.041)
    Double/Take: +0.767
    Double/Pass: +1.000 (+0.233)

    Best Cube action: Double / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 4-ply, cube decisions: XG Roller+
    Search interval: Huge
    Confidence No Double: ± 0.002 (+0.724..+0.728)
    Confidence Double: ± 0.003 (+0.764..+0.770)

    eXtreme Gammon Version: 2.19.207.pre-release

    Ok. I'll Axelise this one. But I'm only doing it from my memory
    of the algo so results aren't 100% guaranteed, but I've done
    a fair few so hopefully I've got the hang of it.

    No adjustments for us.
    For the opponent, there's +1 for the 5point gap and + 3 for the 3 extra crossovers.
    So we get 77 to 86. Add 1/6 to our 77 to get 89 5/6. The difference between 89 5/6 and 86
    is 3 5/6. Since this is >=2 the opponent will take. Since this is <=4, we would double even if
    we owned the cube.

    So the Axelisation works correctly here. In fact, it seems to understand the position very well.
    Big take, marginal redouble.

    Your impression about Isight is quite egregiously wrong. A full database of non-contact positions
    in real games has been consulted, with no preference given to positions where all checkers are in
    the home board.
    Isight counts crossovers and Keith doesn't, which amply explains why Isight is more positive about
    the on-roll player than Keith is.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Sun Jul 24 02:53:39 2022
    On Thursday, July 21, 2022 at 1:57:11 PM UTC+1, Tim Chow wrote:
    XGID=---CCCE----Aa---a-ad-ec---:0:0:1:00:0:0:0:0:10

    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 |
    | | | O O O |
    | | | O O O |
    | | | O O |
    | | | O |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X X X |
    | | | X X X X |
    | O X | | X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 77 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    ---
    Tim Chow

    Could you possibly let me know if this is a redouble?
    For some reason, I am unable to set up positions in XG.
    I do a lot of rollouts but I can only do these from my games.

    Thanks, Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to peps...@gmail.com on Sun Jul 24 08:49:45 2022
    On 7/23/2022 7:28 PM, peps...@gmail.com wrote:

    Your impression about Isight is quite egregiously wrong. A full database of non-contact positions
    in real games has been consulted, with no preference given to positions where all checkers are in
    the home board.

    I've figured out the source of my confusion. I was confusing Isight
    with Joachim Matussek's work.

    https://bkgm.com/articles/Matussek/BearoffGWC.pdf

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to peps...@gmail.com on Sun Jul 24 09:37:13 2022
    On 7/24/2022 5:53 AM, peps...@gmail.com wrote:
    Could you possibly let me know if this is a redouble?
    For some reason, I am unable to set up positions in XG.
    I do a lot of rollouts but I can only do these from my games.

    Possibly a marginal redouble according to the rollout below, but
    only just.

    XGID=---CCCE----Aa---a-ad-ec---:1:1:1:00:0:0:0:0:10

    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 |
    | | | O O O |
    | | | O O O |
    | | | O O |
    | | | O |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X X X | +---+
    | | | X X X X | | 2 |
    | O X | | X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 77 O: 82 X-O: 0-0
    Cube: 2, X own cube
    X on roll, cube action

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 73.49% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.51% (G:0.00% B:0.00%)
    Redouble/Take
    Player Winning Chances: 73.47% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.53% (G:0.00% B:0.00%)

    Cubeful Equities:
    No redouble: +0.763 (-0.004)
    Redouble/Take: +0.767
    Redouble/Pass: +1.000 (+0.233)

    Best Cube action: Redouble / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 4-ply, cube decisions: XG Roller+
    Search interval: Huge
    Confidence No Double: ± 0.002 (+0.761..+0.765)
    Confidence Double: ± 0.003 (+0.764..+0.770)

    eXtreme Gammon Version: 2.19.207.pre-release

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to Tim Chow on Thu Aug 4 11:11:33 2022
    On Saturday, July 23, 2022 at 8:47:14 AM UTC-4, Tim Chow wrote:
    XGID=---CCCE----Aa---a-ad-ec---:0:0:1:00:0:0:0:0:10

    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 |
    | | | O O O |
    | | | O O O |
    | | | O O |
    | | | O |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X X X |
    | | | X X X X |
    | O X | | X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 77 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action
    This time the Keith count says it's a clear ND, which is wrong
    but not wildly wrong. I think it's because O's distribution has
    some flaws that the Keith count fails to account for. Does Isight
    have a different verdict? I have the vague impression that Isight
    is designed for positions where all the checkers are already in the
    home board, but maybe that impression is wrong.


    Analyzed in Rollout
    No double
    Player Winning Chances: 73.48% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.52% (G:0.00% B:0.00%)
    Double/Take
    Player Winning Chances: 73.47% (G:0.00% B:0.00%)
    Opponent Winning Chances: 26.53% (G:0.00% B:0.00%)

    Cubeful Equities:
    No double: +0.726 (-0.041)
    Double/Take: +0.767
    Double/Pass: +1.000 (+0.233)

    Best Cube action: Double / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 4-ply, cube decisions: XG Roller+
    Search interval: Huge
    Confidence No Double: ± 0.002 (+0.724..+0.728)
    Confidence Double: ± 0.003 (+0.764..+0.770)

    eXtreme Gammon Version: 2.19.207.pre-release

    ---
    Tim Chow

    Keith Count says it's a clear ND? First off, isn't it only by 1 pip? Second off, I've posted it many times that the Keith Count at longer lengths should be adjusted.

    ~80-100 pips: double when leading by 5
    ~100-120 pips: double when leading by 6
    ~120-140 pips: double when leading by 7

    Stick

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