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  • I didn't roll an ace

    From Timothy Chow@21:1/5 to All on Mon Sep 5 10:14:00 2022
    XGID=--BBBBB-----bAd---Bc-aBcb-:1:1:1:33:0:0:0:0:10

    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 X | | O O X O O |
    | O X | | O X O O |
    | O | | O O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | | +---+
    | O | | X X X X X | | 2 |
    | O | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 133 O: 100 X-O: 0-0
    Cube: 2, X own cube
    X to play 33

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah...Clem@21:1/5 to Timothy Chow on Tue Sep 6 11:44:49 2022
    On 9/5/2022 10:14 AM, Timothy Chow wrote:
    XGID=--BBBBB-----bAd---Bc-aBcb-:1:1:1:33:0:0:0:0:10

    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           X |   | O     O  X  O  O |
     |    O           X |   | O        X  O  O |  |    O             |   | O           O    |  |    O             |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |   |                  | +---+
     | O                |   | X  X  X  X  X    | | 2 |  | O                |   | X  X  X  X  X    | +---+  +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 133  O: 100 X-O: 0-0
    Cube: 2, X own cube
    X to play 33


    Behind in the race so maintain contact. The checkers on the eighteen
    point stay where they are. I'm not very enthused about slotting the ace
    point but it looks better than the alternatives.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed Sep 7 08:53:01 2022
    XGID=--BBBBB-----bAd---Bc-aBcb-:1:1:1:33:0:0:0:0:10

    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 X | | O O X O O |
    | O X | | O X O O |
    | O | | O O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | | +---+
    | O | | X X X X X | | 2 |
    | O | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 133 O: 100 X-O: 0-0
    Cube: 2, X own cube
    X to play 33

    I think this one is tough. According to general principles, X should
    stay back in order to maximize his chances of getting and hitting a
    shot. On the other hand, 13/1 leaves him totally stripped, with a
    blot in his otherwise killer board. According to the rollout below,
    13/1 is a whopper. But see the variants to get a sense of some of
    the subtleties of the position.

    1. Rollout¹ 18/15(2) 13/7 eq:+0.291
    Player: 53.60% (G:16.30% B:0.33%)
    Opponent: 46.40% (G:5.82% B:0.09%)
    Confidence: ±0.007 (+0.283..+0.298) - [100.0%]

    2. Rollout¹ 13/1 eq:+0.172 (-0.118)
    Player: 49.57% (G:14.24% B:0.31%)
    Opponent: 50.43% (G:10.51% B:0.17%)
    Confidence: ±0.008 (+0.164..+0.181) - [0.0%]

    3. Rollout¹ 18/15(2) 4/1(2) eq:+0.164 (-0.127)
    Player: 47.96% (G:13.62% B:0.18%)
    Opponent: 52.04% (G:7.31% B:0.14%)
    Confidence: ±0.007 (+0.157..+0.171) - [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 1
    ---------

    XGID=-AABBBB-----bAd---Bc-aBcb-:1:1:1:33:0:0:0:0:10

    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 X | | O O X O O |
    | O X | | O X O O |
    | O | | O O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | | +---+
    | O | | X X X X | | 2 |
    | O | | X X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 132 O: 100 X-O: 0-0
    Cube: 2, X own cube
    X to play 33

    1. Rollout¹ 18/15(2) 13/7 eq:+0.092
    Player: 46.48% (G:12.03% B:0.22%)
    Opponent: 53.52% (G:9.15% B:0.24%)
    Confidence: ±0.007 (+0.085..+0.100) - [59.4%]

    2. Rollout¹ 13/1 eq:+0.091 (-0.001)
    Player: 46.88% (G:12.57% B:0.22%)
    Opponent: 53.12% (G:11.15% B:0.18%)
    Confidence: ±0.008 (+0.084..+0.099) - [40.6%]

    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 2
    ---------

    XGID=--BBBBB-----bdA---Bc-aBcb-:1:1:1:33:0:0:0:0:10

    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-+
    | O X X | | O O X O O |
    | O X | | O X O O |
    | O | | O O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | | +---+
    | O | | X X X X X | | 2 |
    | O | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 134 O: 104 X-O: 0-0
    Cube: 2, X own cube
    X to play 33

    1. Rollout¹ 14/2 eq:+0.429
    Player: 56.86% (G:19.17% B:0.40%)
    Opponent: 43.14% (G:7.24% B:0.07%)
    Confidence: ±0.012 (+0.417..+0.441) - [55.8%]

    2. Rollout¹ 18/15(2) 14/8 eq:+0.428 (-0.001)
    Player: 56.29% (G:19.29% B:0.36%)
    Opponent: 43.71% (G:4.50% B:0.07%)
    Confidence: ±0.009 (+0.419..+0.437) - [44.2%]

    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 3
    ---------

    XGID=---BBCC-----bAd---Bc-aBcb-:1:1:1:33:0:0:0:0:10

    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 X | | O O X O O |
    | O X | | O X O O |
    | O | | O O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X | +---+
    | O | | X X X X | | 2 |
    | O | | X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 100 X-O: 0-0
    Cube: 2, X own cube
    X to play 33

    1. Rollout¹ 13/4 5/2 eq:+0.217
    Player: 51.25% (G:14.77% B:0.36%)
    Opponent: 48.75% (G:10.80% B:0.14%)
    Confidence: ±0.009 (+0.208..+0.226) - [100.0%]

    2. Rollout¹ 18/15(2) 13/10 5/2 eq:+0.191 (-0.026)
    Player: 49.73% (G:13.72% B:0.32%)
    Opponent: 50.27% (G:7.72% B:0.13%)
    Confidence: ±0.008 (+0.182..+0.199) - [0.0%]

    3. Rollout¹ 18/15(2) 13/7 eq:+0.189 (-0.028)
    Player: 49.26% (G:13.01% B:0.28%)
    Opponent: 50.74% (G:6.91% B:0.13%)
    Confidence: ±0.009 (+0.181..+0.198) - [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 4
    ---------

    XGID=--ABBCB-----bAd---Bc-aBcb-:1:1:1:33:0:0:0:0:10

    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 X | | O O X O O |
    | O X | | O X O O |
    | O | | O O |
    | O | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X | +---+
    | O | | X X X X | | 2 |
    | O | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 136 O: 100 X-O: 0-0
    Cube: 2, X own cube
    X to play 33

    1. Rollout¹ 18/15(2) 13/10 5/2 eq:+0.298
    Player: 53.26% (G:15.84% B:0.32%)
    Opponent: 46.74% (G:5.59% B:0.07%)
    Confidence: ±0.009 (+0.289..+0.306) - [100.0%]

    2. Rollout¹ 13/4 5/2 eq:+0.261 (-0.037)
    Player: 52.12% (G:15.10% B:0.32%)
    Opponent: 47.88% (G:8.01% B:0.10%)
    Confidence: ±0.008 (+0.253..+0.269) - [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

    ---
    Tim Chow

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