1. Forum
  2. Usenet
  3. REC.GAMES.BACKGAMMON

  • 4pt or 9pt?

    From Timothy Chow@21:1/5 to All on Thu Nov 3 00:31:31 2022
    XGID=-a-a-CB-C-C-cD---aabbbb---:0:0:1:41:0:0:0:0:10

    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 |
    | X | | |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | O X X | | X |
    | O X X | | X X |
    | O X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 133 O: 136 X-O: 0-0
    Cube: 1
    X to play 41

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah...Clem@21:1/5 to Timothy Chow on Fri Nov 4 13:57:07 2022
    On 11/3/2022 12:31 AM, Timothy Chow wrote:
    XGID=-a-a-CB-C-C-cD---aabbbb---:0:0:1:41:0:0:0:0:10

    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       |
     | X                |   |                  |
     | X                |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     | O     X     X    |   |    X             |
     | O     X     X    |   | X  X             |
     | O     X     X    |   | X  X     O     O |  +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 133  O: 136 X-O: 0-0
    Cube: 1
    X to play 41



    Making the four point strips the 8 and 5 while leaving the midpoint
    stacked. Making the nine point looks more flexible and does a better job
    at containment. If the game plan is to prime, then the nine looks
    superior - we'll never make a prime that includes both the ten and the
    four points.

    So, I'll make the nine point here.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sat Nov 5 10:07:13 2022
    XGID=-a-a-CB-C-C-cD---aabbbb---:0:0:1:41:0:0:0:0:10

    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 |
    | X | | |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | O X X | | X |
    | O X X | | X X |
    | O X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 133 O: 136 X-O: 0-0
    Cube: 1
    X to play 41

    I'm tempted to claim that all other things being equal, the 4pt
    is usually slightly better than the 9pt. The trouble is, all
    other things are rarely equal. If you search the BGOnline archives
    for "4pt vs 9pt chow" you'll find about a dozen problems of this
    type.

    In the case at hand, I think ah...Clem analyzed it well, and came
    up with XG's play of 13/9 10/9.

    1. Rollout¹ 13/9 10/9 eq:+0.756
    Player: 70.76% (G:7.53% B:0.18%)
    Opponent: 29.24% (G:3.17% B:0.07%)
    Confidence: ±0.014 (+0.742..+0.770) - [100.0%]

    2. Rollout¹ 8/4 5/4 eq:+0.681 (-0.075)
    Player: 69.21% (G:5.34% B:0.15%)
    Opponent: 30.79% (G:2.63% B:0.05%)
    Confidence: ±0.011 (+0.670..+0.692) - [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 Stick Rice@21:1/5 to Tim Chow on Sat Nov 5 10:15:12 2022
    On Saturday, November 5, 2022 at 10:07:15 AM UTC-4, Tim Chow wrote:
    XGID=-a-a-CB-C-C-cD---aabbbb---:0:0:1:41:0:0:0:0:10

    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 |
    | X | | |
    | X | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | O X X | | X |
    | O X X | | X X |
    | O X X | | X X O O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 133 O: 136 X-O: 0-0
    Cube: 1
    X to play 41
    I'm tempted to claim that all other things being equal, the 4pt
    is usually slightly better than the 9pt. The trouble is, all
    other things are rarely equal. If you search the BGOnline archives
    for "4pt vs 9pt chow" you'll find about a dozen problems of this
    type.

    In the case at hand, I think ah...Clem analyzed it well, and came
    up with XG's play of 13/9 10/9.

    1. Rollout¹ 13/9 10/9 eq:+0.756
    Player: 70.76% (G:7.53% B:0.18%)
    Opponent: 29.24% (G:3.17% B:0.07%)
    Confidence: ±0.014 (+0.742..+0.770) - [100.0%]

    2. Rollout¹ 8/4 5/4 eq:+0.681 (-0.075)
    Player: 69.21% (G:5.34% B:0.15%)
    Opponent: 30.79% (G:2.63% B:0.05%)
    Confidence: ±0.011 (+0.670..+0.692) - [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

    The short version is "if opponent owns or has a blot on your 3pt then make the 9pt...".

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From MK@21:1/5 to Stick Rice on Sat Nov 5 16:48:50 2022
    On November 5, 2022 at 11:15:13 AM UTC-6, Stick Rice wrote:

    The short version is "if opponent owns or
    has a blot on your 3pt then make the 9pt...".

    I wonder how many times the bot/s would
    have followed this "rule of dumb" in Axel's
    3,000 games...? :)

    Since he won't work for me, he won't count
    but if he makes his data public, I will count
    and let you all know. :))

    MK

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