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  • Prime versus prime

    From Timothy Chow@21:1/5 to All on Tue Sep 7 23:03:36 2021
    XGID=-b--ACD-C----B--babccb--B-: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-+
    | X O O O | | O O O X |
    | X O O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | X | | X X | +---+
    | X | | X X O | | 2 |
    | X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 129 X-O: 0-0
    Cube: 2, X own cube
    X to play 51

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Wed Sep 8 01:08:05 2021
    On Wednesday, September 8, 2021 at 4:03:38 AM UTC+1, Tim Chow wrote:
    XGID=-b--ACD-C----B--babccb--B-: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-+
    | X O O O | | O O O X |
    | X O O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | X | | X X | +---+
    | X | | X X O | | 2 |
    | X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 129 X-O: 0-0
    Cube: 2, X own cube
    X to play 51

    ---
    Tim Chow
    It's not very QF-friendly but surely the most natural idea is to extend the prime by 5/4 and then 13/8 is the obvious 5 so I'll play that.
    I can't totally rule out making the 3 point though. So perhaps that's the XG play.
    Anyway, 13/8 5/4 is my response. It's not my answer -- I don't have an answer. But it is my response.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Fri Sep 10 21:54:29 2021
    XGID=-b--ACD-C----B--babccb--B-: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-+
    | X O O O | | O O O X |
    | X O O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | X | | X X | +---+
    | X | | X X O | | 2 |
    | X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 129 X-O: 0-0
    Cube: 2, X own cube
    X to play 51

    X is losing the priming battle, so that justifies taking some risks.
    The fact that O's 2's are somewhat duplicated (to hit and make her
    own 3pt) makes some difference, but even without this duplication,
    XG favors slotting 8/3 (see variant).

    1. Rollout¹ 8/3 5/4 eq:-0.177
    Player: 39.78% (G:12.52% B:0.73%)
    Opponent: 60.22% (G:23.20% B:2.39%)
    Confidence: ±0.012 (-0.189..-0.165) - [100.0%]

    2. Rollout¹ 13/8 5/4 eq:-0.266 (-0.089)
    Player: 35.80% (G:10.42% B:0.53%)
    Opponent: 64.20% (G:20.83% B:1.72%)
    Confidence: ±0.010 (-0.276..-0.257) - [0.0%]

    3. Rollout¹ 8/3 4/3 eq:-0.283 (-0.106)
    Player: 35.22% (G:10.88% B:0.63%)
    Opponent: 64.78% (G:21.11% B:1.65%)
    Confidence: ±0.011 (-0.293..-0.272) - [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=-b--ACD-C----B--babcbc--B-: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-+
    | X O O O | | O O O X |
    | X O O | | O O O X |
    | | | O O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | X |
    | X | | X X | +---+
    | X | | X X O | | 2 |
    | X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 141 O: 128 X-O: 0-0
    Cube: 2, X own cube
    X to play 51

    1. Rollout¹ 8/3 5/4 eq:-0.164
    Player: 40.23% (G:12.67% B:0.79%)
    Opponent: 59.77% (G:23.17% B:2.56%)
    Confidence: ±0.011 (-0.175..-0.153) - [100.0%]

    2. Rollout¹ 13/8 5/4 eq:-0.209 (-0.045)
    Player: 37.68% (G:11.33% B:0.65%)
    Opponent: 62.32% (G:20.56% B:1.56%)
    Confidence: ±0.009 (-0.219..-0.200) - [0.0%]

    3. Rollout¹ 8/3 4/3 eq:-0.239 (-0.074)
    Player: 36.71% (G:11.16% B:0.61%)
    Opponent: 63.29% (G:20.68% B:1.72%)
    Confidence: ±0.010 (-0.248..-0.229) - [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 Thu Feb 24 09:38:55 2022
    XGID=--aBBBCBB--A-----bcdbbaA--:1:-1:1:32:0:0:0:0:10

    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 X | +---+
    | O O | | O O O | | 2 |
    | O | | O | +---+
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | 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: 106 O: 105 X-O: 0-0
    Cube: 2, O own cube
    X to play 32

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sat Feb 26 12:06:46 2022
    XGID=--aBBBCBB--A-----bcdbbaA--:1:-1:1:32:0:0:0:0:10

    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 X | +---+
    | O O | | O O O | | 2 |
    | O | | O | +---+
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | 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: 106 O: 105 X-O: 0-0
    Cube: 2, O own cube
    X to play 32

    Usually, in a priming battle, the right strategy is to do one's best to
    roll it forward smoothly, and not dump any checkers any deeper into
    one's board than the front of the prime. On the other hand, X's timing
    is shaky here and he wants to hold his prime as long as possible; 6/1
    gives him the most spare pips to play with, whereas the alternatives
    give him a slightly awkward distribution of spares. It's a subtle
    tradeoff, as the variant illustrates.

    1. Rollout¹ 6/1 eq:+0.029
    Player: 56.60% (G:11.63% B:0.40%)
    Opponent: 43.40% (G:7.81% B:0.35%)
    Confidence: ±0.010 (+0.019..+0.038) - [100.0%]

    2. Rollout¹ 11/8 6/4 eq:-0.058 (-0.087)
    Player: 53.65% (G:11.08% B:0.39%)
    Opponent: 46.35% (G:8.36% B:0.33%)
    Confidence: ±0.008 (-0.066..-0.050) - [0.0%]

    3. Rollout¹ 11/6 eq:-0.060 (-0.089)
    Player: 53.84% (G:11.57% B:0.42%)
    Opponent: 46.16% (G:8.50% B:0.37%)
    Confidence: ±0.010 (-0.071..-0.050) - [0.0%]

    4. Rollout¹ 11/9 6/3 eq:-0.075 (-0.104)
    Player: 53.23% (G:11.34% B:0.40%)
    Opponent: 46.77% (G:8.90% B:0.36%)
    Confidence: ±0.008 (-0.083..-0.067) - [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=--aBBBCBB---A----bcdbbaA--:1:-1:1:32:0:0:0:0:10

    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 X | +---+
    | O O | | O O O | | 2 |
    | O | | O | +---+
    | | | O |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | 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: 107 O: 105 X-O: 0-0
    Cube: 2, O own cube
    X to play 32

    1. Rollout¹ 12/7 eq:+0.134
    Player: 59.81% (G:13.67% B:0.47%)
    Opponent: 40.19% (G:6.82% B:0.26%)
    Confidence: ±0.009 (+0.125..+0.143) - [100.0%]

    2. Rollout¹ 6/1 eq:+0.090 (-0.044)
    Player: 58.73% (G:12.07% B:0.45%)
    Opponent: 41.27% (G:7.38% B:0.31%)
    Confidence: ±0.009 (+0.081..+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 Axel Reichert@21:1/5 to All on Fri Mar 10 21:03:44 2023
    GNU Backgammon Position ID: bNsoAFhuuxEAKA
    Match ID : UQlgAXAACAAE
    +24-23-22-21-20-19------18-17-16-15-14-13-+ O: gnubg
    | X X O O O O | O | O O O | 7 points
    | O O O O | | O |
    | | | |
    | | | |
    | | | |
    | |BAR| |v 11 point match
    | | | |
    | | | |
    | X X | | |
    | O X X X X X | | | On roll
    | O X X X X X | | X | 1 point
    +-1--2--3--4--5--6-------7--8--9-10-11-12-+ X: axel (Cube: 2)
    Pip counts: O 144, X 103

    Hint: With the checker on the bar it only /looks/ like a broken 6-prime.

    Best regards

    Axel

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to Axel Reichert on Fri Mar 10 17:28:28 2023
    On Friday, March 10, 2023 at 3:03:46 PM UTC-5, Axel Reichert wrote:
    GNU Backgammon Position ID: bNsoAFhuuxEAKA
    Match ID : UQlgAXAACAAE
    +24-23-22-21-20-19------18-17-16-15-14-13-+ O: gnubg
    | X X O O O O | O | O O O | 7 points
    | O O O O | | O |
    | | | |
    | | | |
    | | | |
    | |BAR| |v 11 point match
    | | | |
    | | | |
    | X X | | |
    | O X X X X X | | | On roll
    | O X X X X X | | X | 1 point
    +-1--2--3--4--5--6-------7--8--9-10-11-12-+ X: axel (Cube: 2)
    Pip counts: O 144, X 103

    Hint: With the checker on the bar it only /looks/ like a broken 6-prime.

    Best regards

    Axel

    Clear beaver for money and probably a cube AtS since it's a dead cube and when we do roll well we pocket some gammons that have serious value on a 4 cube at 10a 4a.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From MK@21:1/5 to Axel Reichert on Sat Mar 11 00:45:33 2023
    On March 10, 2023 at 1:03:46 PM UTC-7, Axel Reichert wrote:

    GNU Backgammon Position ID: bNsoAFhuuxEAKA
    Match ID : UQlgAXAACAAE

    Hint: With the checker on the bar it only /looks/ like
    a broken 6-prime.

    Bah humbug!

    Hint: Santa, I want an AI backgammon bot or at least
    an AI gamblegammon bot that can adjust its checker
    play according to the match score, for next Christmas.

    If you can deliver, I will then ask for similar bots that
    can adjust their checker plays according to the "batch"
    score in addition to "match" score. (I think SET for "set
    equity table" was too confusing. So, now I will try BET
    for "batch of matches equity table" to see if it sticks.)

    MK

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From MK@21:1/5 to All on Sat Mar 11 15:55:26 2023
    On March 11, 2023 at 1:45:34 AM UTC-7, MK wrote:

    On March 10, 2023 at 1:03:46 PM UTC-7, Axel Reichert wrote:

    GNU Backgammon Position ID: bNsoAFhuuxEAKA
    Match ID : UQlgAXAACAAE

    Hint: With the checker on the bar it only /looks/
    like a broken 6-prime.

    If you can deliver, I will then ask for similar bots
    that can adjust their checker plays according to
    the "batch" score in addition to "match" score. (I
    think SET for "set equity table" was too confusing.
    So, now I will try BET for "batch of matches equity
    table" to see if it sticks.)

    I am struggling to think of a "match" as a "set of
    matches" and trying to find a new terminology to
    segregate my thoughts but my above comments
    to your post were misplaced. Sorry. :( I will try to
    do better at addressing this in more appropriate
    discussions...

    MK

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to Axel Reichert on Sun Mar 12 08:42:29 2023
    On 3/10/2023 3:03 PM, Axel Reichert wrote:
    GNU Backgammon Position ID: bNsoAFhuuxEAKA
    Match ID : UQlgAXAACAAE
    +24-23-22-21-20-19------18-17-16-15-14-13-+ O: gnubg
    | X X O O O O | O | O O O | 7 points
    | O O O O | | O |
    | | | |
    | | | |
    | | | |
    | |BAR| |v 11 point match
    | | | |
    | | | |
    | X X | | |
    | O X X X X X | | | On roll
    | O X X X X X | | X | 1 point
    +-1--2--3--4--5--6-------7--8--9-10-11-12-+ X: axel (Cube: 2)
    Pip counts: O 144, X 103

    Well, at this score, we're supposed to be trigger-happy with
    the cube, but our straggler on the 24pt, which is not at the
    edge of O's five-prime, gives me pause. I don't think I'd
    double OTB, but maybe the extra gammons from those outfield
    blots make it a double. I would take as O.

    ---
    Tim Chow

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