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  • Bearing off with contact

    From Timothy Chow@21:1/5 to All on Wed Jun 22 08:57:37 2022
    XGID=-BBaBBD------a-----bbcbbb-:1:-1:1:32:0:0:0:0:10

    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 | | 2 |
    | | | O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | | | X X X X X |
    | | | X X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 48 O: 80 X-O: 0-0
    Cube: 2, O own cube
    X to play 32

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Wed Jun 22 08:35:31 2022
    On Wednesday, June 22, 2022 at 1:57:40 PM UTC+1, Tim Chow wrote:
    XGID=-BBaBBD------a-----bbcbbb-:1:-1:1:32:0:0:0:0:10

    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 | | 2 |
    | | | O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | | | X X X X X |
    | | | X X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 48 O: 80 X-O: 0-0
    Cube: 2, O own cube
    X to play 32

    I want to watch the next episode of the DMP Rule Show!
    The candidate plays are 6/1, 6/3*/1 and 4/2 4/1.
    6/3*/1 is by far the most natural play.
    But Tim does have a QF bias. Even if he says, he does some anti-QF posts,
    I think that excellence in his classes is helped with a bit of QF common sense. So, by QF logic, 4/2 4/1 must be right.
    It does less shotleaving than the other plays.
    Note that if 4/2 4/1 is right here, it must be super-right when we don't care about gammons.
    4/2 4/1 is my play but I would never do this OTB.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sun Jun 26 09:51:07 2022
    XGID=-BBaBBD------a-----bbcbbb-:1:-1:1:32:0:0:0:0:10

    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 | | 2 |
    | | | O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | | | X X X X X |
    | | | X X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 48 O: 80 X-O: 0-0
    Cube: 2, O own cube
    X to play 32

    This is a bad roll (only 63 is worse, according to XG). X is faced
    with a choice between the lesser of two evils: create an interior
    gap on the 4pt, or leave himself with a single spare checker on
    the 6pt. Neither option is pleasant, but it's important to note
    that there is a good chance that O will have to leave soon. This
    tips the balance in favor of 4/2 4/1, since 6/1 has greater blotting
    risk in the short term. See the variant for comparison.

    Note that 6/3*/1 is the wrong idea, since that creates longer-term
    blotting risk without enough extra gammons to compensate.

    1. Rollout¹ 4/2 4/1 eq:+0.827
    Player: 91.73% (G:1.95% B:0.01%)
    Opponent: 8.27% (G:0.00% B:0.00%)
    Confidence: ±0.002 (+0.825..+0.829) - [100.0%]

    2. Rollout¹ 6/1 eq:+0.793 (-0.034)
    Player: 90.51% (G:1.83% B:0.01%)
    Opponent: 9.49% (G:0.00% B:0.00%)
    Confidence: ±0.002 (+0.791..+0.795) - [0.0%]

    3. Rollout¹ 6/3* 3/1 eq:+0.685 (-0.142)
    Player: 84.07% (G:6.14% B:0.04%)
    Opponent: 15.93% (G:0.00% B:0.00%)
    Confidence: ±0.002 (+0.683..+0.687) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 4-ply, cube decisions: XG Roller+
    Search interval: Large

    eXtreme Gammon Version: 2.19.207.pre-release

    -------
    Variant
    -------

    XGID=-BBbBBD------------bbcbbb-:1:-1:1:32:0:0:0:0:10

    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 | | 2 |
    | | | O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | | | X X X O X X |
    | | | X X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 48 O: 90 X-O: 0-0
    Cube: 2, O own cube
    X to play 32

    1. Rollout¹ 6/1 eq:+0.773
    Player: 87.91% (G:6.18% B:0.04%)
    Opponent: 12.09% (G:0.00% B:0.00%)
    Confidence: ±0.002 (+0.771..+0.775) - [54.6%]

    2. Rollout¹ 4/2 4/1 eq:+0.773
    Player: 87.88% (G:6.03% B:0.04%)
    Opponent: 12.12% (G:0.00% B:0.00%)
    Confidence: ±0.002 (+0.771..+0.774) - [45.4%]

    ¹ 2592 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)