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  • Holding game, sort of

    From Timothy Chow@21:1/5 to All on Sat Aug 6 09:21:46 2022
    XGID=--BBBBB----Ab-c--B-bbBcab-:0:0:1:62:0:0:0:0:10

    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 | | O O X O O O |
    | O X | | O O X O O |
    | O | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O | | X X X X X |
    | O X | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 94 X-O: 0-0
    Cube: 1
    X to play 62

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sat Aug 6 12:08:53 2022
    On 8/6/2022 9:21 AM, Timothy Chow wrote:
    XGID=--BBBBB----Ab-c--B-bbBcab-:0:0:1:62:0:0:0:0:10

    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    |   | O  O  X  O  O  O |
     |    O        X    |   | O  O  X  O     O |
     |    O             |   |          O       |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |                  |   |                  |
     | O                |   | X  X  X  X  X    |
     | O  X             |   | X  X  X  X  X    |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 127  O: 94 X-O: 0-0
    Cube: 1
    X to play 62


    OTB I'd probably just play 11/3 without much deliberation. Can't say
    I'm seeing anything better. I want to hold the anchor and her board is
    strong enough that I'm not eager to volunteer a shot. So 11/3 it is.


    --
    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 Aug 8 09:36:44 2022
    XGID=--BBBBB----Ab-c--B-bbBcab-:0:0:1:62:0:0:0:0:10

    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 | | O O X O O O |
    | O X | | O O X O O |
    | O | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O | | X X X X X |
    | O X | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 94 X-O: 0-0
    Cube: 1
    X to play 62

    What a difference a blot makes! I played the pedestrian 11/3, but
    XG insists on gaining some flexibility by breaking the back anchor.
    Of course this would not be a viable play if O's board were stronger
    (see variant 1), but it's also interesting to see what happens if
    the roll is changed to 51 (see variant 2). Duplication of aces plays
    less of a role than I thought, and timing considerations (spare pips)
    are more important than I thought.

    1. Rollout¹ 21/13 eq:-0.363
    Player: 40.92% (G:8.58% B:0.22%)
    Opponent: 59.08% (G:10.55% B:0.09%)
    Confidence: ±0.010 (-0.374..-0.353) - [100.0%]

    2. Rollout¹ 21/15 11/9 eq:-0.401 (-0.037)
    Player: 39.68% (G:8.01% B:0.22%)
    Opponent: 60.32% (G:12.48% B:0.11%)
    Confidence: ±0.010 (-0.411..-0.390) - [0.0%]

    3. Rollout¹ 11/3 eq:-0.477 (-0.113)
    Player: 37.35% (G:7.31% B:0.19%)
    Opponent: 62.65% (G:10.81% B:0.09%)
    Confidence: ±0.010 (-0.487..-0.467) - [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=--BBBBB----Ab-c--B-bbBbbb-:0:0:1:62:0:0:0:0:10

    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 | | O O X O O O |
    | O X | | O O X O O O |
    | O | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O | | X X X X X |
    | O X | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 93 X-O: 0-0
    Cube: 1
    X to play 62

    1. XG Roller++ 11/3 eq:-0.582
    Player: 35.05% (G:6.21% B:0.15%)
    Opponent: 64.95% (G:12.53% B:0.10%)

    2. XG Roller++ 11/5 3/1 eq:-0.823 (-0.241)
    Player: 30.24% (G:3.96% B:0.06%)
    Opponent: 69.76% (G:15.87% B:0.39%)

    3. XG Roller++ 11/5 4/2 eq:-0.843 (-0.261)
    Player: 29.43% (G:3.69% B:0.08%)
    Opponent: 70.57% (G:14.30% B:0.28%)

    4. XG Roller++ 21/13 eq:-0.853 (-0.271)
    Player: 34.06% (G:7.70% B:0.21%)
    Opponent: 65.94% (G:27.16% B:0.26%)

    eXtreme Gammon Version: 2.19.207.pre-release

    ---------
    Variant 2
    ---------

    XGID=--BBBBB----Ab-c--B-bbBcab-:0:0:1:51:0:0:0:0:10

    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 | | O O X O O O |
    | O X | | O O X O O |
    | O | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | |
    | O | | X X X X X |
    | O X | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 94 X-O: 0-0
    Cube: 1
    X to play 51

    1. Rollout¹ 21/15 eq:-0.407
    Player: 40.02% (G:8.21% B:0.22%)
    Opponent: 59.98% (G:13.28% B:0.11%)
    Confidence: ±0.010 (-0.417..-0.396) - [82.3%]

    2. Rollout¹ 21/16 11/10 eq:-0.413 (-0.007)
    Player: 40.19% (G:9.53% B:0.29%)
    Opponent: 59.81% (G:17.02% B:0.13%)
    Confidence: ±0.010 (-0.423..-0.403) - [17.7%]

    3. Rollout¹ 11/5 eq:-0.430 (-0.023)
    Player: 38.75% (G:7.71% B:0.20%)
    Opponent: 61.25% (G:10.77% B:0.09%)
    Confidence: ±0.011 (-0.441..-0.419) - [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 Timothy Chow@21:1/5 to All on Wed Apr 12 09:21:31 2023
    XGID=-ABB-aBaE---aC--a--cbbbb--:0:0:1:64:0:0:0:0:10

    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 O O |
    | X | | O O O O O |
    | X | | O |
    | | | |
    | | | |
    | |BAR| |
    | X | | |
    | X | | |
    | X | | |
    | X | | X X X |
    | O X O | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 102 O: 106 X-O: 0-0
    Cube: 1
    X to play 64

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Timothy Chow on Wed Apr 12 09:03:45 2023
    On Wednesday, April 12, 2023 at 9:21:35 AM UTC-4, Timothy Chow wrote:
    XGID=-ABB-aBaE---aC--a--cbbbb--:0:0:1:64:0:0:0:0:10

    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 O O |
    | X | | O O O O O |
    | X | | O |
    | | | |
    | | | |
    | |BAR| |
    | X | | |
    | X | | |
    | X | | |
    | X | | X X X |
    | O X O | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 102 O: 106 X-O: 0-0
    Cube: 1
    X to play 64

    ---
    Tim Chow
    X is in the lead. Get the spare on the midpoint home safely, maybe get some doubles for the midpoint later, and while you're waiting, play from the eight. You might even create some threes if you can play some fours from the 8 point stack.
    13/3, no hit.
    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Robert Zimmerman on Wed Apr 12 09:06:35 2023
    On Wednesday, April 12, 2023 at 12:03:46 PM UTC-4, Robert Zimmerman wrote:
    On Wednesday, April 12, 2023 at 9:21:35 AM UTC-4, Timothy Chow wrote:
    XGID=-ABB-aBaE---aC--a--cbbbb--:0:0:1:64:0:0:0:0:10

    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 O O |
    | X | | O O O O O |
    | X | | O |
    | | | |
    | | | |
    | |BAR| |
    | X | | |
    | X | | |
    | X | | |
    | X | | X X X |
    | O X O | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 102 O: 106 X-O: 0-0
    Cube: 1
    X to play 64

    ---
    Tim Chow
    X is in the lead. Get the spare on the midpoint home safely, maybe get some doubles for the midpoint later, and while you're waiting, play from the eight. You might even create some threes if you can play some fours from the 8 point stack.
    13/3, no hit.
    Bob
    OK, I want a do-over. I gave Paul one maybe a month ago. I was onto the creating 3's idea, and neglected to note that the opportunity was staring me in the face. Play both numbers from the 8 point.
    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Fri Apr 14 07:41:12 2023
    XGID=-ABB-aBaE---aC--a--cbbbb--:0:0:1:64:0:0:0:0:10

    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 O O |
    | X | | O O O O O |
    | X | | O |
    | | | |
    | | | |
    | |BAR| |
    | X | | |
    | X | | |
    | X | | |
    | X | | X X X |
    | O X O | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 102 O: 106 X-O: 0-0
    Cube: 1
    X to play 64

    Usually, preparing to clear the midpoint is the right strategy for the
    holdee. However, here, 13/3 creates a highly inflexible position. As
    Bob notes, X has no good 3's to play.

    1. Rollout¹ 8/4 8/2 eq:+0.395
    Player: 61.57% (G:2.90% B:0.04%)
    Opponent: 38.43% (G:2.79% B:0.06%)
    Confidence: ±0.008 (+0.388..+0.403) - [100.0%]

    2. Rollout¹ 13/3 eq:+0.286 (-0.110)
    Player: 57.97% (G:3.03% B:0.06%)
    Opponent: 42.03% (G:4.64% B:0.09%)
    Confidence: ±0.009 (+0.277..+0.295) - [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

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

    XGID=-ABB-aCaD---aC--a--cbbbb--:0:0:1:64:0:0:0:0:10

    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 O O |
    | X | | O O O O O |
    | X | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | X | | |
    | X | | X |
    | X | | X X X |
    | O X O | | X O X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 100 O: 106 X-O: 0-0
    Cube: 1
    X to play 64

    1. Rollout¹ 13/3 eq:+0.450
    Player: 63.30% (G:2.56% B:0.04%)
    Opponent: 36.70% (G:2.76% B:0.06%)
    Confidence: ±0.008 (+0.442..+0.458) - [92.5%]

    2. Rollout¹ 8/4 8/2 eq:+0.442 (-0.009)
    Player: 63.57% (G:3.10% B:0.04%)
    Opponent: 36.43% (G:2.66% B:0.05%)
    Confidence: ±0.009 (+0.433..+0.450) - [7.5%]

    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)