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  • 65 to play

    From Timothy Chow@21:1/5 to All on Tue Feb 21 10:14:48 2023
    XGID=-a-A-BBCB-b-bC---dbdB-----:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | |
    | O O X X | | X X |
    | O O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 150 X-O: 0-0
    Cube: 1
    X to play 65

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to Timothy Chow on Tue Feb 21 13:52:42 2023
    On Tuesday, February 21, 2023 at 10:14:50 AM UTC-5, Timothy Chow wrote:
    XGID=-a-A-BBCB-b-bC---dbdB-----:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | |
    | O O X X | | X X |
    | O O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 150 X-O: 0-0
    Cube: 1
    X to play 65

    ---
    Tim Chow

    The five is forced and there are only two legit sixes so everyone should get this right at least half of the time. Why would we hit when that checker is on the point we want it to be on? (and the blitz follow up is a bit lame oc)

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Thu Feb 23 15:00:43 2023
    XGID=-a-A-BBCB-b-bC---dbdB-----:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | |
    | O O X X | | X X |
    | O O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 150 X-O: 0-0
    Cube: 1
    X to play 65

    I didn't like stacking up another spare on the bar point. But X has
    a clear advantage here and doesn't need to jeopardize it by giving
    O a direct shot.

    1. Rollout¹ 13/7 8/3 eq:+0.558
    Player: 61.60% (G:20.96% B:0.53%)
    Opponent: 38.40% (G:5.42% B:0.24%)
    Confidence: ±0.015 (+0.543..+0.574) - [100.0%]

    2. Rollout¹ 8/3 7/1* eq:+0.396 (-0.162)
    Player: 57.98% (G:19.42% B:0.40%)
    Opponent: 42.02% (G:6.32% B:0.25%)
    Confidence: ±0.015 (+0.381..+0.411) - [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=-a-A-BBCB-b-bC---dbd---B--:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | |
    | O O X X | | X X |
    | O O X X | | X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 147 O: 150 X-O: 0-0
    Cube: 1
    X to play 65

    1. Rollout¹ 8/3 7/1* eq:-0.044
    Player: 46.84% (G:18.32% B:0.45%)
    Opponent: 53.16% (G:11.88% B:0.57%)
    Confidence: ±0.015 (-0.059..-0.029) - [97.5%]

    2. Rollout¹ 13/7 8/3 eq:-0.066 (-0.021)
    Player: 46.59% (G:17.18% B:0.57%)
    Opponent: 53.41% (G:12.29% B:0.62%)
    Confidence: ±0.015 (-0.081..-0.051) - [2.5%]

    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)
  • From Timothy Chow@21:1/5 to All on Wed Sep 13 09:44:57 2023
    XGID=-B-BBdCBB-A----a-bbbbbA---:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O | | O O O X |
    | O O | | O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | O |
    | | | X O |
    | X X | | X O X X X |
    | X X X | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 96 O: 150 X-O: 0-0
    Cube: 1
    X to play 65

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Wed Sep 13 11:05:55 2023
    On 9/13/2023 9:44 AM, Timothy Chow wrote:
    XGID=-B-BBdCBB-A----a-bbbbbA---:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     |       O     O  O |   | O  O  O  X       |
     |             O  O |   | O  O  O          |
     |                  |   |                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |    O             |
     |                  |   | X  O             |
     |             X  X |   | X  O  X  X     X |
     |       X     X  X |   | X  O  X  X     X |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 96  O: 150 X-O: 0-0
    Cube: 1
    X to play 65

    Sixes don't grow on trees, so leaping the prime looks thematic...


    ...but leaving a double shot against the five prime seems very risky.

    And the re-but is that if X plays safe here, O will easily move her
    checkers into the outfield making it hard for X to escape later even if
    he rolls a six to do so. I count ten rolls that miss, and those are not
    great odds but seems better than sitting behind the blockade waiting to
    lose.

    22/11.
    --
    Ah....Clem
    The future is fun, the future is fair.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From MK@21:1/5 to ah....Clem on Thu Sep 14 01:51:04 2023
    On September 13, 2023 at 9:05:57 AM UTC-6, ah....Clem wrote:

    On 9/13/2023 9:44 AM, Timothy Chow wrote:

    XGID=-B-BBdCBB-A----a-bbbbbA---:0:0:1:65:0:0:0:0:10

    Sixes don't grow on trees, so leaping the
    prime looks thematic...

    Not if you apply Tim's math "21^7 < 2^32 < 21^8".

    Are you playing dumb or are you really dumb...?

    MK

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Fri Sep 15 08:24:33 2023
    XGID=-B-BBdCBB-A----a-bbbbbA---:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O | | O O O X |
    | O O | | O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | O |
    | | | X O |
    | X X | | X O X X X |
    | X X X | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 96 O: 150 X-O: 0-0
    Cube: 1
    X to play 65

    Jumping out with the 6 is certainly the right idea, but there are
    two candidates for the 5: 16/11 and 6/1. The most important
    difference between the two plays is that 16/11 leaves 24 shots
    while 6/1 leaves 20 shots.

    According to XG, after 22/16 6/1, O can take if she rolls 66 or
    44 or 64, whereas after 22/11, O must pass if she misses. This
    is a point in favor of 22/11, but it's not enough to compensate
    for the 4 extra shots.

    1. Rollout¹ 22/16 6/1 eq:-0.081
    Player: 47.21% (G:9.50% B:0.06%)
    Opponent: 52.79% (G:11.68% B:0.38%)
    Confidence: ±0.009 (-0.090..-0.073) - [100.0%]

    2. Rollout¹ 22/11 eq:-0.262 (-0.181)
    Player: 44.60% (G:6.96% B:0.06%)
    Opponent: 55.40% (G:9.68% B:0.31%)
    Confidence: ±0.006 (-0.267..-0.256) - [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)