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  • Another opportunity to make the 4pt

    From Timothy Chow@21:1/5 to All on Tue Mar 14 09:38:17 2023
    XGID=-aa--BCBAAA-bC--ac-e--b-B-:0:0:1:62:0:0:0:0:10

    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 |
    | X O | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X | | X X |
    | O X X X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 156 O: 142 X-O: 0-0
    Cube: 1
    X to play 62

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Timothy Chow on Tue Mar 14 11:14:10 2023
    On Tuesday, March 14, 2023 at 9:38:20 AM UTC-4, Timothy Chow wrote:
    XGID=-aa--BCBAAA-bC--ac-e--b-B-:0:0:1:62:0:0:0:0:10

    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 |
    | X O | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X | | X X |
    | O X X X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 156 O: 142 X-O: 0-0
    Cube: 1
    X to play 62

    ---
    Tim Chow

    Make the four point. Fewer shots and fewer blots for a point that is strengthened by the 5 and bar points.

    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From [email protected]@21:1/5 to Robert Zimmerman on Tue Mar 14 13:17:26 2023
    On Tuesday, March 14, 2023 at 6:14:13 PM UTC, Robert Zimmerman wrote:
    On Tuesday, March 14, 2023 at 9:38:20 AM UTC-4, Timothy Chow wrote:
    XGID=-aa--BCBAAA-bC--ac-e--b-B-:0:0:1:62:0:0:0:0:10

    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 |
    | X O | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X | | X X |
    | O X X X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 156 O: 142 X-O: 0-0
    Cube: 1
    X to play 62

    ---
    Tim Chow
    Make the four point. Fewer shots and fewer blots for a point that is strengthened by the 5 and bar points.

    I think that, if you see it, it's fairly clear that 13/7 10/8 is best. It makes a powerful four prime that is difficult
    to jump and prepares to extend the prime even further. It also leaves fewer shots than the other candidate plays.
    Hitting doesn't achieve that much and helps the opponent to anchor in our inner board.

    13/7 10/8, hoping for a "Not much to add to Paul's analysis..." to come with the rollout.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Thu Mar 16 09:27:05 2023
    XGID=-aa--BCBAAA-bC--ac-e--b-B-:0:0:1:62:0:0:0:0:10

    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 |
    | X O | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X | | X X |
    | O X X X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 156 O: 142 X-O: 0-0
    Cube: 1
    X to play 62

    I think there's a pretty good chance I'd hit if something like this
    came up again, especially since XG hits in the variant below. But
    I think the reasoning goes something like this. When the opponent
    has rolled an awkward early 55 like this, priming is usually the
    best game plan. The situation is complicated here by the fact that
    O is aiming at our blot on the 8pt. Making the 4pt gives us an
    excellent chance of making a killer five-prime from the 4pt to the
    8pt, but only if we're missed. Is it worth the risk? XG says yes.
    X will usually have a very strong cube, possibly D/P, if O does not
    immediately hit.

    The other priming play, 13/7 10/8, cleans up the blot, but it's not
    so easy to make the 4pt after that.

    1. Rollout¹ 10/4 6/4 eq:+0.564
    Player: 64.46% (G:21.71% B:1.20%)
    Opponent: 35.54% (G:12.67% B:1.03%)
    Confidence: ±0.014 (+0.550..+0.578) - [100.0%]

    2. Rollout¹ 24/16* eq:+0.487 (-0.077)
    Player: 63.20% (G:19.69% B:1.52%)
    Opponent: 36.80% (G:14.20% B:1.43%)
    Confidence: ±0.018 (+0.469..+0.505) - [0.0%]

    3. Rollout¹ 13/7 10/8 eq:+0.473 (-0.091)
    Player: 62.03% (G:20.13% B:1.16%)
    Opponent: 37.97% (G:13.20% B:0.82%)
    Confidence: ±0.016 (+0.456..+0.489) - [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=-aa--BCBA-A-bD--ac-e--b-B-:0:0:1:62:0:0:0:0:10

    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 |
    | X O | | O |
    | X | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O X | | X X |
    | O X X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 160 O: 142 X-O: 0-0
    Cube: 1
    X to play 62

    1. Rollout¹ 24/16* eq:+0.475
    Player: 62.43% (G:17.54% B:1.13%)
    Opponent: 37.57% (G:12.75% B:0.84%)
    Confidence: ±0.015 (+0.460..+0.489) - [94.2%]

    2. Rollout¹ 10/4 6/4 eq:+0.458 (-0.017)
    Player: 61.75% (G:19.33% B:1.07%)
    Opponent: 38.25% (G:13.16% B:0.98%)
    Confidence: ±0.015 (+0.444..+0.473) - [5.7%]

    3. Rollout¹ 13/7 10/8 eq:+0.443 (-0.031)
    Player: 61.00% (G:19.31% B:0.99%)
    Opponent: 39.00% (G:13.22% B:0.66%)
    Confidence: ±0.015 (+0.429..+0.458) - [0.1%]

    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)