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  • Doublets are tricky to play

    From Timothy Chow@21:1/5 to All on Sat Oct 22 11:35:55 2022
    XGID=--b-BBE-----c----cBcBb-bAA:1:-1:1:55:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O X O O X | +---+
    | O X | | O X O O | | 2 |
    | O | | O | +---+
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | | | X |
    | O | | X |
    | O | | X X X O |
    | O | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 173 O: 139 X-O: 0-0
    Cube: 2, O own cube
    X to play 55

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sat Oct 22 15:11:01 2022
    On 10/22/2022 11:35 AM, Timothy Chow wrote:
    XGID=--b-BBE-----c----cBcBb-bAA:1:-1:1:55:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     |             O  X |   | O  X  O     O  X | +---+
     |             O  X |   | O  X  O     O    | | 2 |
     |             O    |   | O                | +---+
     |                  |   |                  |
     |                  | X |                  |
     |                  |BAR|                  |
     |                  |   | X                |
     |                  |   | X                |
     | O                |   | X                |
     | O                |   | X  X  X     O    |
     | O                |   | X  X  X     O    |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 173  O: 139 X-O: 0-0
    Cube: 2, O own cube
    X to play 55


    I often get these quite wrong, but here goes anyway:

    Burying checkers on the ace seems anti-positional. The rearmost checker
    is stuck. One five is forced to enter, which leaves three more fives to
    play.

    20/15(3) looks playable - if the game plan is to transition to a bar
    point holding game that play does it. It also does a nice job of
    outfield control and gives the straggler more chances to rest there than keeping the 20 point.

    Re-making the midpoint has it's merits, but how to play the final five?
    6/1 buries a checker which i'm reluctant to do.

    I'll go with bar/15 20/15(2), but without much conviction.



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

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From badgolferman@21:1/5 to Timothy Chow on Sat Oct 22 19:15:51 2022
    Timothy Chow wrote:

    XGID=--b-BBE-----c----cBcBb-bAA:1:-1:1:55:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O X O O X | +---+
    | O X | | O X O O | | 2 |
    | O | | O | +---+
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | | | X |
    | O | | X |
    | O | | X X X O |
    | O | | X X X O | +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 173 O: 139 X-O: 0-0
    Cube: 2, O own cube
    X to play 55

    ---
    Tim Chow

    I think I'd just play Bar/5 and maintain the status quo for another
    turn. If O happens to run one of their back checkers now I will have
    two chances to hit it.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Mon Oct 24 08:19:10 2022
    XGID=--b-BBE-----c----cBcBb-bAA:1:-1:1:55:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O X O O X | +---+
    | O X | | O X O O | | 2 |
    | O | | O | +---+
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | | | X |
    | O | | X |
    | O | | X X X O |
    | O | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 173 O: 139 X-O: 0-0
    Cube: 2, O own cube
    X to play 55

    A general rule of thumb is that the bar-point and 5pt anchors don't
    work very well together. This roll allows X to re-establish his
    midpoint and re-connect his somewhat disconnected position.

    1. Rollout¹ Bar/15 18/13(2) eq:-0.134
    Player: 50.94% (G:17.63% B:0.57%)
    Opponent: 49.06% (G:13.44% B:0.60%)
    Confidence: ±0.010 (-0.144..-0.124) - [100.0%]

    2. Rollout¹ Bar/15 20/15(2) eq:-0.206 (-0.072)
    Player: 49.07% (G:15.70% B:0.49%)
    Opponent: 50.93% (G:15.82% B:0.61%)
    Confidence: ±0.011 (-0.217..-0.195) - [0.0%]

    3. Rollout¹ Bar/5 eq:-0.210 (-0.076)
    Player: 48.17% (G:15.92% B:0.46%)
    Opponent: 51.83% (G:12.81% B:0.52%)
    Confidence: ±0.010 (-0.220..-0.200) - [0.0%]

    4. Rollout¹ Bar/20 18/13(2) 6/1 eq:-0.237 (-0.103)
    Player: 47.55% (G:16.08% B:0.39%)
    Opponent: 52.45% (G:13.33% B:0.57%)
    Confidence: ±0.011 (-0.248..-0.226) - [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

    ---
    Tim Chow

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