• Another "Pottle or not?" problem

    From Timothy Chow@21:1/5 to All on Thu Oct 6 08:21:45 2022
    XGID=--a-BaD-BB--bD-b-b-cb-b-A-:0:0:1:53:0:0:0:0:10

    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-+
    | X O O | | O O O X |
    | X O O | | O O O |
    | X | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X |
    | O X X | | X O X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 142 O: 139 X-O: 0-0
    Cube: 1
    X to play 53

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sat Oct 8 08:31:14 2022
    XGID=--a-BaD-BB--bD-b-b-cb-b-A-:0:0:1:53:0:0:0:0:10

    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-+
    | X O O | | O O O X |
    | X O O | | O O O |
    | X | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X |
    | O X X | | X O X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 142 O: 139 X-O: 0-0
    Cube: 1
    X to play 53

    I think this one is difficult, especially if you compare it with the
    variant below. In the variant, O's 4's are duplicated after 24/16,
    and the rollout slightly favors 24/16 despite the extra gammon wins
    afforded by 13/5*. In the actual position, though, the rollout says
    that 24/16 is a whopper.

    1. Rollout¹ 13/5* eq:-0.192
    Player: 46.49% (G:14.62% B:0.84%)
    Opponent: 53.51% (G:19.32% B:0.87%)
    Confidence: ±0.014 (-0.205..-0.178) - [100.0%]

    2. Rollout¹ 24/16 eq:-0.297 (-0.105)
    Player: 44.57% (G:6.84% B:0.38%)
    Opponent: 55.43% (G:17.78% B:0.37%)
    Confidence: ±0.013 (-0.310..-0.284) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.207.pre-release

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

    XGID=-a--BaD-BB--bD-b-b-cb-b-A-:0:0:1:53:0:0:0:0:10

    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-+
    | X O O | | O O O X |
    | X O O | | O O O |
    | X | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X |
    | O X X | | X X |
    | O X X | | X O X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 142 O: 140 X-O: 0-0
    Cube: 1
    X to play 53

    1. Rollout¹ 24/16 eq:-0.193
    Player: 47.41% (G:8.34% B:0.46%)
    Opponent: 52.59% (G:18.36% B:0.49%)
    Confidence: ±0.007 (-0.199..-0.186) - [100.0%]

    2. Rollout¹ 13/5* eq:-0.217 (-0.024)
    Player: 46.06% (G:14.83% B:0.81%)
    Opponent: 53.94% (G:20.40% B:0.96%)
    Confidence: ±0.008 (-0.224..-0.209) - [0.0%]

    ¹ 5184 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)