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  • Mutual holding game, sort of

    From Timothy Chow@21:1/5 to All on Sat Aug 26 09:32:46 2023
    XGID=-BBBb-BA-B---B---dccb-Ba--:0:0:1:53:0:0:0:0:10

    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 O |
    | X O O | | O O X |
    | O O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | X | | X O 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: 119 O: 125 X-O: 0-0
    Cube: 1
    X to play 53

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Wed Aug 30 21:27:47 2023
    On 8/26/2023 9:32 AM, Timothy Chow wrote:
    XGID=-BBBb-BA-B---B---dccb-Ba--:0:0:1:53:0:0:0:0:10

    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  O    |
     | X           O  O |   | O  O     X       |
     |             O  O |   | O                |
     |             O    |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |   |                  |
     |          X       |   | X     O  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: 119  O: 125 X-O: 0-0
    Cube: 1
    X to play 53

    O is outboarded, which might imply a bold play, but X is ahead in the
    race which implies safer play. O's homeboard blot tilts it toward bold,
    plus there is no safe play.

    Slot the five point? Looks risky, but I'll give it a shot. 13/5.

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

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Mon Sep 11 09:19:15 2023
    XGID=-BBBb-BA-B---B---dccb-Ba--:0:0:1:53:0:0:0:0:10

    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 O |
    | X O O | | O O X |
    | O O | | O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | X | | X O 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: 119 O: 125 X-O: 0-0
    Cube: 1
    X to play 53

    The relatively safe play of 13/10 7/2 is inflexible and kills a
    checker. On the other hand, 13/5 volunteers a double shot. OTB,
    I thought that was too much, but according to the rollout, Magriel's
    criteria prevail again.

    1. Rollout¹ 13/5 eq:-0.689
    Player: 33.30% (G:9.30% B:0.18%)
    Opponent: 66.70% (G:20.57% B:1.03%)
    Confidence: ±0.015 (-0.704..-0.673) - [100.0%]

    2. Rollout¹ 13/10 7/2 eq:-0.782 (-0.094)
    Player: 30.90% (G:6.06% B:0.11%)
    Opponent: 69.10% (G:17.59% B:0.70%)
    Confidence: ±0.013 (-0.796..-0.769) - [0.0%]

    3. Rollout¹ 9/6 7/2 eq:-0.811 (-0.122)
    Player: 29.91% (G:5.86% B:0.09%)
    Opponent: 70.09% (G:16.54% B:0.63%)
    Confidence: ±0.014 (-0.825..-0.797) - [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)
  • From MK@21:1/5 to Timothy Chow on Thu Sep 14 01:18:26 2023
    On September 11, 2023 at 7:19:19 AM UTC-6, Timothy Chow wrote:

    XGID=-BBBb-BA-B---B---dccb-Ba--:0:0:1:53:0:0:0:0:10
    The relatively safe play of 13/10 7/2 is inflexible...
    1. Rollout¹ 13/5 eq:-0.689

    The incorrect but the best play here is 13/10 13/8

    Ex-Gee is using 32-bit Mersenne Twister RNG and
    applies modulo 6 to produce dice rolls.

    I've used your "given math" "21^7 < 2^32 < 21^8" to
    deduce the seed after 8-9 rolls and saw that Ex-Gee
    will roll a 55 next... ;)

    MK

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