• Hit or play safe?

    From Timothy Chow@21:1/5 to All on Mon Jan 24 09:18:00 2022
    XGID=--BDbcDC-aB--------abbbb--:1:-1:1:51:0:0:0:0:10

    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 O O O O | +---+
    | | | O O O O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X X |
    | X | | X O X |
    | X X | | X O O X X |
    | X O X | | X O O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 81 O: 152 X-O: 0-0
    Cube: 2, O own cube
    X to play 51

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed Jan 26 09:47:41 2022
    XGID=--BDbcDC-aB--------abbbb--:1:-1:1:51:0:0:0:0:10

    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 O O O O | +---+
    | | | O O O O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X X |
    | X | | X O X |
    | X X | | X O O X X |
    | X O X | | X O O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 81 O: 152 X-O: 0-0
    Cube: 2, O own cube
    X to play 51

    Hitting wins more gammons, but is it worth the risk of leaving return
    shots from the bar? In this position, XG thinks so, because O's
    offensive position has some weaknesses. But see the variant below.

    1. Rollout¹ 10/9* 7/2 eq:+0.290
    Player: 58.72% (G:37.18% B:0.56%)
    Opponent: 41.28% (G:8.67% B:0.32%)
    Confidence: ±0.013 (+0.277..+0.303) - [100.0%]

    2. Rollout¹ 7/1 eq:+0.212 (-0.078)
    Player: 58.67% (G:24.96% B:0.27%)
    Opponent: 41.33% (G:5.18% B:0.18%)
    Confidence: ±0.010 (+0.202..+0.222) - [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=--BDbcDC-aB--------bbbba--:1:-1:1:51:0:0:0:0:10

    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 O O O O | +---+
    | | | O O O O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X X |
    | X | | X O X |
    | X X | | X O O X X |
    | X O X | | X O O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 81 O: 156 X-O: 0-0
    Cube: 2, O own cube
    X to play 51

    1. Rollout¹ 7/1 eq:+0.145
    Player: 56.27% (G:24.95% B:0.23%)
    Opponent: 43.73% (G:5.39% B:0.16%)
    Confidence: ±0.010 (+0.136..+0.155) - [100.0%]

    2. Rollout¹ 7/2 3/2 eq:+0.109 (-0.037)
    Player: 55.24% (G:24.02% B:0.18%)
    Opponent: 44.76% (G:6.20% B:0.19%)
    Confidence: ±0.010 (+0.098..+0.119) - [0.0%]

    3. Rollout¹ 10/9* 7/2 eq:+0.099 (-0.046)
    Player: 52.88% (G:34.56% B:0.48%)
    Opponent: 47.12% (G:9.95% B:0.36%)
    Confidence: ±0.012 (+0.087..+0.112) - [0.0%]

    4. Rollout¹ 6/1 3/2 eq:+0.090 (-0.055)
    Player: 54.97% (G:23.61% B:0.20%)
    Opponent: 45.03% (G:6.44% B:0.20%)
    Confidence: ±0.009 (+0.080..+0.099) - [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 Sun Feb 12 09:11:12 2023
    XGID=----bCE-a-B--Da--bbcbb--A-:1:1:1:65:0:0:0:0:10

    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 |
    | X O O | | O O O |
    | X | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X | +---+
    | X | | X X O | | 2 |
    | X O | | X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 136 X-O: 0-0
    Cube: 2, X own cube
    X to play 65

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Timothy Chow on Sun Feb 12 10:13:41 2023
    On Sunday, February 12, 2023 at 9:11:13 AM UTC-5, Timothy Chow wrote:
    XGID=----bCE-a-B--Da--bbcbb--A-:1:1:1:65:0:0:0:0:10

    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 |
    | X O O | | O O O |
    | X | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X | +---+
    | X | | X X O | | 2 |
    | X O | | X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 136 X-O: 0-0
    Cube: 2, X own cube
    X to play 65

    ---
    Tim Chow

    Everything about this position calls for a safe play by the usual (Magriel) criteria, so the question is which is safest, to hit or not. Or maybe this is not the right position to even apply those criteria.
    This doesn't seem like a position where the race and gaining minimal ground by hitting are even a remote consideration.
    Reasons to hit that I can think of are to disconnect O's checkers, slow her formation of the prime, and maybe to create a tempo problem for O. I don't think giving a direct shot to the opponent in our home board could be characterized as a tempo play.
    Making the prime by slotting the back and covering looks difficult for O without breaking the anchor. So I'd be left with disconnecting O's checkers. If our checkers on the 10 point were one or two pips closer to home I'd feel better about how things
    would go in the outfield. Right now they don't serve as a great stepping stone for the midpoint, and I think there will be more blots for O to pick up. Sending white backward might actually give her more opportunities in the outfield if she doesn't hit
    our home board blot. So I would play "safest" with no hit on the way in. 13/7/2.

    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Tue Feb 14 10:17:38 2023
    XGID=----bCE-a-B--Da--bbcbb--A-:1:1:1:65:0:0:0:0:10

    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 |
    | X O O | | O O O |
    | X | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | X |
    | | | X |
    | | | X X | +---+
    | X | | X X O | | 2 |
    | X O | | X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 136 X-O: 0-0
    Cube: 2, X own cube
    X to play 65

    I was surprised that XG favored the bold play here, since Magriel's
    criteria seem to suggest safe play. I think the key point is that
    X's straggler is in a lot of trouble, and X needs some counterplay.
    Hitting is the only counterplay this roll affords him; if he plays
    passively, then he's probably just going to get slowly crushed.

    Even if X had a blot on his 1pt, XG thinks it's a close decision
    (see variant).

    1. Rollout¹ 13/8* 8/2 eq:-0.461
    Player: 29.95% (G:7.25% B:0.23%)
    Opponent: 70.05% (G:23.69% B:1.02%)
    Confidence: ±0.008 (-0.469..-0.453) - [100.0%]

    2. Rollout¹ 13/2 eq:-0.535 (-0.074)
    Player: 26.56% (G:5.80% B:0.19%)
    Opponent: 73.44% (G:21.67% B:0.78%)
    Confidence: ±0.009 (-0.544..-0.526) - [0.0%]

    3. Rollout¹ 13/7 13/8* eq:-0.550 (-0.089)
    Player: 27.90% (G:6.73% B:0.28%)
    Opponent: 72.10% (G:26.78% B:1.57%)
    Confidence: ±0.008 (-0.559..-0.542) - [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=-A--bCD-a-B--Da--bbcbb--A-:1:1:1:65:0:0:0:0:10

    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 |
    | X O O | | O O O |
    | X | | O |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | | | X X | +---+
    | X | | X X O | | 2 |
    | X O | | X X O X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 136 O: 136 X-O: 0-0
    Cube: 2, X own cube
    X to play 65

    1. Rollout¹ 13/2 eq:-0.562
    Player: 25.48% (G:5.97% B:0.18%)
    Opponent: 74.52% (G:21.88% B:0.84%)
    Confidence: ±0.006 (-0.568..-0.557) - [63.7%]

    2. Rollout¹ 13/8* 8/2 eq:-0.564 (-0.002)
    Player: 27.70% (G:6.61% B:0.22%)
    Opponent: 72.30% (G:27.28% B:1.39%)
    Confidence: ±0.007 (-0.571..-0.557) - [33.4%]

    3. Rollout¹ 13/7 6/1 eq:-0.569 (-0.006)
    Player: 25.61% (G:6.13% B:0.19%)
    Opponent: 74.39% (G:23.11% B:0.91%)
    Confidence: ±0.006 (-0.574..-0.563) - [2.9%]

    ¹ 2592 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)
  • From Timothy Chow@21:1/5 to All on Thu Mar 23 09:14:42 2023
    XGID=-A-BaCBB--b-bC---dbdB-----:0:0:1:51:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O O X | | X X X |
    | O O X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 147 X-O: 0-0
    Cube: 1
    X to play 51

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Timothy Chow on Thu Mar 23 07:36:56 2023
    On Thursday, March 23, 2023 at 9:14:45 AM UTC-4, Timothy Chow wrote:
    XGID=-A-BaCBB--b-bC---dbdB-----:0:0:1:51:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O O X | | X X X |
    | O O X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 147 X-O: 0-0
    Cube: 1
    X to play 51

    ---
    Tim Chow

    Tempting, but I think it's winnable playing safe given the 26 point lead. Are there enough gammons in there to make attacking a worthwhile venture? Possibly, but I'm guessing no.

    13/7

    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sat Mar 25 09:54:19 2023
    XGID=-A-BaCBB--b-bC---dbdB-----:0:0:1:51:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O O X | | X X X |
    | O O X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 147 X-O: 0-0
    Cube: 1
    X to play 51

    I didn't like risking my race lead by giving X a double shot from the
    bar, but a stronger board and 11 checkers in the zone cover over a
    multitude of sins. See the variant below for comparison.

    1. Rollout¹ 13/8 5/4* eq:+0.411
    Player: 56.91% (G:23.60% B:0.38%)
    Opponent: 43.09% (G:6.97% B:0.29%)
    Confidence: ±0.012 (+0.399..+0.424) - [100.0%]

    2. Rollout¹ 13/7 eq:+0.307 (-0.104)
    Player: 58.08% (G:14.23% B:0.20%)
    Opponent: 41.92% (G:5.11% B:0.22%)
    Confidence: ±0.015 (+0.292..+0.323) - [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=-A-BaCBB--b-bC---cbcBb----:0:0:1:51:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | X O O | | O X O |
    | X O | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O O X | | X X X |
    | O O X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 141 X-O: 0-0
    Cube: 1
    X to play 51

    1. Rollout¹ 13/7 eq:+0.181
    Player: 54.77% (G:11.40% B:0.17%)
    Opponent: 45.23% (G:4.93% B:0.22%)
    Confidence: ±0.012 (+0.169..+0.192) - [95.5%]

    2. Rollout¹ 13/8 5/4* eq:+0.164 (-0.017)
    Player: 51.27% (G:19.70% B:0.39%)
    Opponent: 48.73% (G:9.03% B:0.44%)
    Confidence: ±0.016 (+0.148..+0.180) - [4.5%]

    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)
  • From Stick Rice@21:1/5 to Timothy Chow on Sat Mar 25 14:36:39 2023
    On Saturday, March 25, 2023 at 9:54:22 AM UTC-4, Timothy Chow wrote:
    XGID=-A-BaCBB--b-bC---dbdB-----:0:0:1:51:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O O X | | X X X |
    | O O X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 147 X-O: 0-0
    Cube: 1
    X to play 51
    I didn't like risking my race lead by giving X a double shot from the
    bar, but a stronger board and 11 checkers in the zone cover over a
    multitude of sins. See the variant below for comparison.

    1. Rollout¹ 13/8 5/4* eq:+0.411
    Player: 56.91% (G:23.60% B:0.38%)
    Opponent: 43.09% (G:6.97% B:0.29%)
    Confidence: ±0.012 (+0.399..+0.424) - [100.0%]

    2. Rollout¹ 13/7 eq:+0.307 (-0.104)
    Player: 58.08% (G:14.23% B:0.20%)
    Opponent: 41.92% (G:5.11% B:0.22%)
    Confidence: ±0.015 (+0.292..+0.323) - [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=-A-BaCBB--b-bC---cbcBb----:0:0:1:51:0:0:0:0:10
    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | X O O | | O X O |
    | X O | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O O X | | X X X |
    | O O X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 141 X-O: 0-0
    Cube: 1
    X to play 51
    1. Rollout¹ 13/7 eq:+0.181
    Player: 54.77% (G:11.40% B:0.17%)
    Opponent: 45.23% (G:4.93% B:0.22%)
    Confidence: ±0.012 (+0.169..+0.192) - [95.5%]

    2. Rollout¹ 13/8 5/4* eq:+0.164 (-0.017)
    Player: 51.27% (G:19.70% B:0.39%)
    Opponent: 48.73% (G:9.03% B:0.44%)
    Confidence: ±0.016 (+0.148..+0.180) - [4.5%]

    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

    You can't look at it as a double shot. While we'd rather not be hit at all of course, if we get hit on the ace point, meh, bfd. We motor on and hope to find a clean entering four from the bar, and we'll take a clean entering five.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to Stick Rice on Sat Mar 25 18:22:57 2023
    On 3/25/2023 5:36 PM, Stick Rice wrote:
    You can't look at it as a double shot. While we'd rather not be hit at all of course, if we get hit on the ace point, meh, bfd. We motor on and hope to find a clean entering four from the bar, and we'll take a clean entering five.
    Your comment suggested to me the variant below. XG still
    prefers to hit, but the equity difference is closer.

    XGID=--BAaCBB--b-bC---dbdB-----:0:0:1:51:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X |
    | X O O | | O X |
    | X O | | O |
    | O | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | O O X | | X X X |
    | O O X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 127 O: 147 X-O: 0-0
    Cube: 1
    X to play 51

    1. Rollout¹ 13/8 5/4* eq:+0.354
    Player: 55.60% (G:23.34% B:0.38%)
    Opponent: 44.40% (G:7.08% B:0.30%)
    Confidence: ±0.008 (+0.346..+0.362) - [100.0%]

    2. Rollout¹ 13/7 eq:+0.305 (-0.049)
    Player: 58.06% (G:14.48% B:0.27%)
    Opponent: 41.94% (G:4.88% B:0.21%)
    Confidence: ±0.011 (+0.295..+0.316) - [0.0%]

    ¹ 2592 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)
  • From Timothy Chow@21:1/5 to All on Fri May 12 09:14:11 2023
    XGID=--AbCBCBBa---B-----bbbbbb-:1:-1:1:64:0:0:0:0:10

    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 O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X X | | X X X O |
    | O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 98 O: 102 X-O: 0-0
    Cube: 2, O own cube
    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 Fri May 12 06:44:35 2023
    On Friday, May 12, 2023 at 9:15:53 AM UTC-4, Timothy Chow wrote:
    XGID=--AbCBCBBa---B-----bbbbbb-:1:-1:1:64:0:0:0:0:10

    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 O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X X | | X X X O |
    | O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 98 O: 102 X-O: 0-0
    Cube: 2, O own cube
    X to play 64

    ---
    Tim Chow
    I'm thinking if you hit and O comes in on the one point, you end up with some more potential difficulties bearing in, on top of the 8 immediate hits O will have to steal the game. I would play safe.
    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to Timothy Chow on Fri May 12 13:14:38 2023
    On Friday, May 12, 2023 at 9:15:53 AM UTC-4, Timothy Chow wrote:
    XGID=--AbCBCBBa---B-----bbbbbb-:1:-1:1:64:0:0:0:0:10

    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 O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X X | | X X X O |
    | O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 98 O: 102 X-O: 0-0
    Cube: 2, O own cube
    X to play 64

    ---
    Tim Chow

    XGID=--AbCBCBBa---B----bbbbbb--:1:-1:1:64:0:0:0:0:10

    The obvious variant.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sun May 14 08:26:06 2023
    XGID=--AbCBCBBa---B-----bbbbbb-:1:-1:1:64:0:0:0:0:10

    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 O | | 2 |
    | | | | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X X | | X X X O |
    | O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 98 O: 102 X-O: 0-0
    Cube: 2, O own cube
    X to play 64

    If we hit, then there's a choice between covering with 8/2 and keeping
    the five-prime with 13/7. What can go wrong if we hit? We could get
    hit back, and then while we're dancing, O escapes. Covering 8/2
    reduces the immediate return shots, but keeping the five-prime is more important, since it significantly increases the chances that O will
    collapse her board.

    But should we hit at all? We could play safe with 8/4 8/2. What can
    go wrong then? The race is then even. O can probably hang on to her
    anchor while her blot saunters around the board. Meanwhile, we might
    leave at least an indirect shot and get hit. Or there might be no
    hitting and we might lose the race.

    According to the rollout, hitting 13/9* 13/7 is better. The variant I
    had prepared is similar to Stick's in that it gives O a little more time
    to win the priming battle, should a priming battle emerge.

    1. Rollout¹ 13/7 13/9* eq:+0.487
    Player: 74.94% (G:12.54% B:0.36%)
    Opponent: 25.06% (G:6.35% B:0.05%)
    Confidence: ±0.006 (+0.481..+0.493) - [100.0%]

    2. Rollout¹ 8/4 8/2 eq:+0.434 (-0.053)
    Player: 73.20% (G:4.93% B:0.08%)
    Opponent: 26.80% (G:1.32% B:0.02%)
    Confidence: ±0.005 (+0.429..+0.438) - [0.0%]

    3. Rollout¹ 13/9* 8/2 eq:+0.287 (-0.199)
    Player: 69.90% (G:10.13% B:0.18%)
    Opponent: 30.10% (G:15.90% B:0.86%)
    Confidence: ±0.004 (+0.283..+0.292) - [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=--AbCBCBBa---B-----cbbcb--:1:-1:1:64:0:0:0:0:10

    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 | +---+
    | X | | O O O O O | | 2 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X X | | X X X O |
    | O X X | | X X X O X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 98 O: 109 X-O: 0-0
    Cube: 2, O own cube
    X to play 64

    1. Rollout¹ 8/4 8/2 eq:+0.487
    Player: 75.88% (G:4.93% B:0.07%)
    Opponent: 24.12% (G:1.33% B:0.04%)
    Confidence: ±0.004 (+0.483..+0.491) - [100.0%]

    2. Rollout¹ 13/7 13/9* eq:+0.472 (-0.015)
    Player: 74.39% (G:12.47% B:0.33%)
    Opponent: 25.61% (G:6.51% B:0.10%)
    Confidence: ±0.008 (+0.464..+0.480) - [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

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Thu Dec 7 09:55:06 2023
    XGID=--aBBCCB--A-----bbbbcBba--:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O | | O O X O O |
    | O O O | | O O X O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X | | X X X X |
    | X X | | X X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 113 O: 106 X-O: 0-0
    Cube: 1
    X to play 65

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Tue Dec 12 09:46:00 2023
    XGID=--aBBCCB--A-----bbbbcBba--:0:0:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O | | O O X O O |
    | O O O | | O O X O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X | | X X X X |
    | X X | | X X X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 113 O: 106 X-O: 0-0
    Cube: 1
    X to play 65

    XG regards every play here to be at least a double whopper, except
    for the hit-and-split play of 21/15 7/2*.

    1. Rollout¹ 21/15 7/2* eq:+0.265
    Player: 58.44% (G:19.42% B:0.91%)
    Opponent: 41.56% (G:19.63% B:2.85%)
    Confidence: ±0.009 (+0.257..+0.274) - [100.0%]

    2. Rollout¹ 10/4 6/1 eq:+0.026 (-0.239)
    Player: 51.34% (G:8.53% B:0.19%)
    Opponent: 48.66% (G:6.37% B:0.22%)
    Confidence: ±0.011 (+0.015..+0.037) - [0.0%]

    3. Rollout¹ 10/4 7/2* eq:-0.020 (-0.285)
    Player: 49.11% (G:14.07% B:0.33%)
    Opponent: 50.89% (G:10.11% B:0.34%)
    Confidence: ±0.011 (-0.031..-0.009) - [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

    ---
    Tim Chow

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