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  • Pottle or not? 4

    From Timothy Chow@21:1/5 to All on Fri Mar 11 14:43:27 2022
    XGID=-B-BAbB-B-B-bC--b--d--bcA-:0:0:1:64:0:0:0:0:10

    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 X |
    | X O | | O O O |
    | X | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O X X | | X O X X |
    | O X X | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 123 O: 120 X-O: 0-0
    Cube: 1
    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 Sun Mar 13 08:52:36 2022
    XGID=-B-BAbB-B-B-bC--b--d--bcA-:0:0:1:64:0:0:0:0:10

    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 X |
    | X O | | O O O |
    | X | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O X X | | X O X X |
    | O X X | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 123 O: 120 X-O: 0-0
    Cube: 1
    X to play 64

    Pottling would seem to be thematic here---this roll puts X slightly
    ahead in the pip count, and O's midpoint is stripped. However, there
    is an attractive and constructive alternative play, 10/6 10/4. X's
    straggler is not in much danger of being attacked or primed, so XG
    favors 10/6 10/4.

    In the variant, I have shifted X's blot from his 4pt to his 2pt. Now
    the alternative play of 8/4 8/2 is not as attractive.

    1. Rollout¹ 10/6 10/4 eq:+0.106
    Player: 53.65% (G:8.57% B:0.26%)
    Opponent: 46.35% (G:8.38% B:0.12%)
    Confidence: ±0.009 (+0.098..+0.115) - [100.0%]

    2. Rollout¹ 24/14 eq:+0.006 (-0.101)
    Player: 51.25% (G:5.44% B:0.23%)
    Opponent: 48.75% (G:9.57% B:0.18%)
    Confidence: ±0.009 (-0.003..+0.015) - [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=-BAB-bB-B-B-bC--b--d--bcA-:0:0:1:64:0:0:0:0:10

    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 X |
    | X O | | O O O |
    | X | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O X X | | X O X X |
    | O X X | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 121 O: 120 X-O: 0-0
    Cube: 1
    X to play 64

    1. Rollout¹ 24/14 eq:-0.008
    Player: 51.18% (G:5.53% B:0.20%)
    Opponent: 48.82% (G:10.98% B:0.25%)
    Confidence: ±0.012 (-0.020..+0.005) - [96.7%]

    2. Rollout¹ 8/4 8/2 eq:-0.022 (-0.015)
    Player: 50.46% (G:11.60% B:0.30%)
    Opponent: 49.54% (G:13.22% B:0.25%)
    Confidence: ±0.010 (-0.033..-0.012) - [3.3%]

    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 Sun Mar 13 20:36:40 2022
    On Sunday, March 13, 2022 at 8:52:41 AM UTC-4, Tim Chow wrote:
    XGID=-B-BAbB-B-B-bC--b--d--bcA-:0:0:1:64:0:0:0:0:10

    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 X |
    | X O | | O O O |
    | X | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O X X | | X O X X |
    | O X X | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 123 O: 120 X-O: 0-0
    Cube: 1
    X to play 64
    Pottling would seem to be thematic here---this roll puts X slightly
    ahead in the pip count, and O's midpoint is stripped. However, there
    is an attractive and constructive alternative play, 10/6 10/4. X's
    straggler is not in much danger of being attacked or primed, so XG
    favors 10/6 10/4.

    In the variant, I have shifted X's blot from his 4pt to his 2pt. Now
    the alternative play of 8/4 8/2 is not as attractive.

    1. Rollout¹ 10/6 10/4 eq:+0.106
    Player: 53.65% (G:8.57% B:0.26%)
    Opponent: 46.35% (G:8.38% B:0.12%)
    Confidence: ±0.009 (+0.098..+0.115) - [100.0%]

    2. Rollout¹ 24/14 eq:+0.006 (-0.101)
    Player: 51.25% (G:5.44% B:0.23%)
    Opponent: 48.75% (G:9.57% B:0.18%)
    Confidence: ±0.009 (-0.003..+0.015) - [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=-BAB-bB-B-B-bC--b--d--bcA-:0:0:1:64:0:0:0:0:10
    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 X |
    | X O | | O O O |
    | X | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O X X | | X O X X |
    | O X X | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 121 O: 120 X-O: 0-0
    Cube: 1
    X to play 64
    1. Rollout¹ 24/14 eq:-0.008
    Player: 51.18% (G:5.53% B:0.20%)
    Opponent: 48.82% (G:10.98% B:0.25%)
    Confidence: ±0.012 (-0.020..+0.005) - [96.7%]

    2. Rollout¹ 8/4 8/2 eq:-0.022 (-0.015)
    Player: 50.46% (G:11.60% B:0.30%)
    Opponent: 49.54% (G:13.22% B:0.25%)
    Confidence: ±0.010 (-0.033..-0.012) - [3.3%]

    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

    The variant should be lifting the blot then running is clear otherwise strengthening/making the board has too much value.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to Stick Rice on Mon Mar 14 08:32:04 2022
    On 3/13/2022 11:36 PM, Stick Rice wrote:
    The variant should be lifting the blot then running is clear otherwise strengthening/making the board has too much value.

    Lifting the blot is certainly *a* variant, but the tradeoff between
    running and strengthening the board is a common theme in Pottle
    problems, and not often discussed.

    ---
    Tim Chow

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