• Too risky to hit? 2

    From Tim Chow@21:1/5 to All on Mon Dec 27 08:25:03 2021
    XGID=-BC-BBBbBa---B-----bbccb--:2:-1:1:64:0:0:0:0:10

    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 | | O O O O O | | 4 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | X O | | X X X X X |
    | O X O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 80 O: 99 X-O: 0-0
    Cube: 4, O own cube
    X to play 64

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed Dec 29 08:44:16 2021
    XGID=-BC-BBBbBa---B-----bbccb--:2:-1:1:64:0:0:0:0:10

    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 | | O O O O O | | 4 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | X O | | X X X X X |
    | O X O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 80 O: 99 X-O: 0-0
    Cube: 4, O own cube
    X to play 64

    According to XG, despite O's fearsome board, not only is it not
    too risky to hit, it's best to slot the 3pt and give O a direct
    shot from the bar.

    The location of the cube is relevant here. Suppose that X had
    cube access. Then XG says that X would have had a double before
    the roll. But suppose X did not double. Then 13/9* 8/2 would
    already lose X's market by a mile if O were to dance, so 9/3
    would be overkill. But with O owning the cube, 9/3 wins a lot
    more extra gammons for X than it loses.

    1. Rollout¹ 13/9* 9/3 eq:+0.338
    Player: 64.50% (G:24.16% B:0.06%)
    Opponent: 35.50% (G:12.21% B:0.37%)
    Confidence: ±0.004 (+0.335..+0.342) - [100.0%]

    2. Rollout¹ 13/9* 8/2 eq:+0.219 (-0.120)
    Player: 63.49% (G:16.29% B:0.05%)
    Opponent: 36.51% (G:14.00% B:0.96%)
    Confidence: ±0.004 (+0.214..+0.223) - [0.0%]

    3. Rollout¹ 8/4 8/2 eq:+0.153 (-0.186)
    Player: 61.88% (G:2.21% B:0.01%)
    Opponent: 38.12% (G:2.19% B:0.07%)
    Confidence: ±0.004 (+0.148..+0.157) - [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)
  • From Stick Rice@21:1/5 to Tim Chow on Sat Jan 1 16:18:56 2022
    On Wednesday, December 29, 2021 at 8:44:24 AM UTC-5, Tim Chow wrote:
    XGID=-BC-BBBbBa---B-----bbccb--:2:-1:1:64:0:0:0:0:10

    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 | | O O O O O | | 4 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | X O | | X X X X X |
    | O X O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 80 O: 99 X-O: 0-0
    Cube: 4, O own cube
    X to play 64
    According to XG, despite O's fearsome board, not only is it not
    too risky to hit, it's best to slot the 3pt and give O a direct
    shot from the bar.

    The location of the cube is relevant here. Suppose that X had
    cube access. Then XG says that X would have had a double before
    the roll. But suppose X did not double. Then 13/9* 8/2 would
    already lose X's market by a mile if O were to dance, so 9/3
    would be overkill. But with O owning the cube, 9/3 wins a lot
    more extra gammons for X than it loses.

    1. Rollout¹ 13/9* 9/3 eq:+0.338
    Player: 64.50% (G:24.16% B:0.06%)
    Opponent: 35.50% (G:12.21% B:0.37%)
    Confidence: ±0.004 (+0.335..+0.342) - [100.0%]

    2. Rollout¹ 13/9* 8/2 eq:+0.219 (-0.120)
    Player: 63.49% (G:16.29% B:0.05%)
    Opponent: 36.51% (G:14.00% B:0.96%)
    Confidence: ±0.004 (+0.214..+0.223) - [0.0%]

    3. Rollout¹ 8/4 8/2 eq:+0.153 (-0.186)
    Player: 61.88% (G:2.21% B:0.01%)
    Opponent: 38.12% (G:2.19% B:0.07%)
    Confidence: ±0.004 (+0.148..+0.157) - [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

    If you owned the cube you can't think that after not doubling before this roll (obvious blunder) the same player would know to double after any of the other sequences. He might think it's too good. Certainly a smaller error than not cubing now.

    Stick

    --- SoupGate-Win32 v1.05
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