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  • Offense or defense?

    From Timothy Chow@21:1/5 to All on Thu Feb 2 09:29:40 2023
    XGID=--aB-BC-CAA-----bccccC----: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-+
    | O O O | | O O X |
    | O O O | | O O X |
    | O O | | O O X |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X | +---+
    | X | | X X X | | 2 |
    | X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to Tim Chow on Thu Feb 2 12:45:41 2023
    On Thursday, February 2, 2023 at 9:29:42 AM UTC-5, Tim Chow wrote:
    XGID=--aB-BC-CAA-----bccccC----: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-+
    | O O O | | O O X |
    | O O O | | O O X |
    | O O | | O O X |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X | +---+
    | X | | X X X | | 2 |
    | X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64

    ---
    Tim Chow

    Both differing candidate plays are offensive.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Fri Feb 3 16:04:23 2023
    On Thursday, February 2, 2023 at 2:29:42 PM UTC, Tim Chow wrote:
    XGID=--aB-BC-CAA-----bccccC----: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-+
    | O O O | | O O X |
    | O O O | | O O X |
    | O O | | O O X |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X | +---+
    | X | | X X X | | 2 |
    | X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64

    Of course, as a mere mortal, from my
    standpoint, there are three trillion plays
    that might be correct -- it's not a question
    (for me) of "both candidates".

    I don't want three stuck behind your prime
    so I will spring with the 6 21/15.
    And now I think 9/5 offers fairly good containment.
    The opponent needs a lot of luck to escape and we're
    nicely prepared to attack on the next roll.
    21/15 9/5

    Paul

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Fri Feb 3 20:28:07 2023
    On 2/2/2023 9:29 AM, Timothy Chow wrote:
    XGID=--aB-BC-CAA-----bccccC----: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-+
     |          O  O  O |   | O  O  X          |
     |          O  O  O |   | O  O  X          |
     |             O  O |   | O  O  X          |
     |                  |   |                  |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |             X    |   | X                | +---+
     |             X    |   | X  X     X       | | 2 |
     |       X  X  X    |   | X  X     X  O    | +---+
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 140  O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64


    Without looking at the diagram, I'm probably going to go with offense
    because that is my nature.

    Now, looking at the diagram, making the four point seems more
    "offensive" than the POH play. So I'll do that. Presumably the defensive
    play is to leap out and either run to the eleven or safety one of the
    blots in X's outfield?

    Might the hybrid escape and hit (21/15 6/2*) be better than either?
    Won't be surprised if that's the bot play, but I'll just block and hope
    O crunches before she escapes.

    --
    Ah....Clem
    The future is fun, the future is fair.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Stick Rice on Fri Feb 3 20:30:13 2023
    On 2/2/2023 3:45 PM, Stick Rice wrote:

    Both differing candidate plays are offensive.

    My top two plays are also "offensive". Because that's my nature.

    But I'm also not sure that either is correct.

    --
    Ah....Clem
    The future is fun, the future is fair.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to ah....Clem on Sat Feb 4 02:29:12 2023
    On Saturday, February 4, 2023 at 1:30:15 AM UTC, ah....Clem wrote:
    On 2/2/2023 3:45 PM, Stick Rice wrote:

    Both differing candidate plays are offensive.
    My top two plays are also "offensive". Because that's my nature.

    But I'm also not sure that either is correct.

    I have more than two candidates so I don't know exactly what Stick means.
    I would think that a defensive play a) springs with 21/15 and b) doesn't
    give the opponent a direct shot. And I would also think that non-defensive plays (by that definition) can be defined as being offensive (in true maths-defining style).
    I also think it's rather likely that Stick is playing on words here. By "offensive",
    he might mean [offends me by showing such poor backgammon play].
    So Stick might be saying: The correct play is an offensive play and other
    plays (whether offensive or defensive) offend him by being so inept.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sat Feb 4 10:04:51 2023
    XGID=--aB-BC-CAA-----bccccC----: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-+
    | O O O | | O O X |
    | O O O | | O O X |
    | O O | | O O X |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X | +---+
    | X | | X X X | | 2 |
    | X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64

    X is running short of time and needs to use the 6 to leap O's
    five-prime. The main candidate play that doesn't involve 21/15
    is making the 4pt, which makes 5 points out of 6, but makes it
    hard for X to improve his position further unless he rolls
    another 6 immediately.

    My variant this time changes the position more than most of my
    variants do, but I wanted to illustrate what happens if X has a
    bit more time and has the option of making his bar point instead
    of his 4pt.

    As for Stick's comment, I suspect he's pointing out that 21/15
    is not a purely defensive play, but helps with the job of
    containing O's straggler.

    1. Rollout¹ 21/15 9/5 eq:+0.020
    Player: 43.05% (G:7.38% B:0.16%)
    Opponent: 56.95% (G:7.27% B:0.25%)
    Confidence: ±0.008 (+0.013..+0.028) - [84.0%]

    2. Rollout¹ 21/11 eq:+0.015 (-0.006)
    Player: 43.27% (G:7.48% B:0.20%)
    Opponent: 56.73% (G:8.38% B:0.27%)
    Confidence: ±0.008 (+0.007..+0.023) - [16.0%]

    3. Rollout¹ 21/15 10/6 eq:-0.018 (-0.038)
    Player: 41.75% (G:6.75% B:0.16%)
    Opponent: 58.25% (G:7.06% B:0.23%)
    Confidence: ±0.007 (-0.025..-0.010) - [0.0%]

    4. Rollout¹ 21/15 8/4 eq:-0.049 (-0.069)
    Player: 42.27% (G:7.76% B:0.18%)
    Opponent: 57.73% (G:13.13% B:0.51%)
    Confidence: ±0.010 (-0.058..-0.039) - [0.0%]

    5. Rollout¹ 10/4 8/4 eq:-0.087 (-0.107)
    Player: 39.23% (G:6.38% B:0.13%)
    Opponent: 60.77% (G:6.99% B:0.18%)
    Confidence: ±0.009 (-0.096..-0.078) - [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=--aB-BC-C--A-A--bccccC----: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 X |
    | O O | | O O X |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X | +---+
    | X | | X X X | | 2 |
    | X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 145 O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64

    1. Rollout¹ 13/7 11/7 eq:+0.097
    Player: 46.67% (G:7.31% B:0.18%)
    Opponent: 53.33% (G:8.62% B:0.17%)
    Confidence: ±0.010 (+0.087..+0.106) - [100.0%]

    2. Rollout¹ 21/15 11/7 eq:+0.064 (-0.033)
    Player: 46.17% (G:7.53% B:0.20%)
    Opponent: 53.83% (G:12.04% B:0.36%)
    Confidence: ±0.010 (+0.053..+0.074) - [0.0%]

    3. Rollout¹ 21/11 eq:+0.043 (-0.054)
    Player: 44.14% (G:7.45% B:0.20%)
    Opponent: 55.86% (G:8.11% B:0.25%)
    Confidence: ±0.008 (+0.035..+0.051) - [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 pepstein5@gmail.com@21:1/5 to Tim Chow on Sat Feb 4 10:17:13 2023
    On Saturday, February 4, 2023 at 3:04:53 PM UTC, Tim Chow wrote:
    XGID=--aB-BC-CAA-----bccccC----: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-+
    | O O O | | O O X |
    | O O O | | O O X |
    | O O | | O O X |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X | +---+
    | X | | X X X | | 2 |
    | X X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64
    X is running short of time and needs to use the 6 to leap O's
    five-prime. The main candidate play that doesn't involve 21/15
    is making the 4pt, which makes 5 points out of 6, but makes it
    hard for X to improve his position further unless he rolls
    another 6 immediately.

    My variant this time changes the position more than most of my
    variants do, but I wanted to illustrate what happens if X has a
    bit more time and has the option of making his bar point instead
    of his 4pt.

    As for Stick's comment, I suspect he's pointing out that 21/15
    is not a purely defensive play, but helps with the job of
    containing O's straggler.

    1. Rollout¹ 21/15 9/5 eq:+0.020
    Player: 43.05% (G:7.38% B:0.16%)
    Opponent: 56.95% (G:7.27% B:0.25%)
    Confidence: ±0.008 (+0.013..+0.028) - [84.0%]

    2. Rollout¹ 21/11 eq:+0.015 (-0.006)
    Player: 43.27% (G:7.48% B:0.20%)
    Opponent: 56.73% (G:8.38% B:0.27%)
    Confidence: ±0.008 (+0.007..+0.023) - [16.0%]

    3. Rollout¹ 21/15 10/6 eq:-0.018 (-0.038)
    Player: 41.75% (G:6.75% B:0.16%)
    Opponent: 58.25% (G:7.06% B:0.23%)
    Confidence: ±0.007 (-0.025..-0.010) - [0.0%]

    4. Rollout¹ 21/15 8/4 eq:-0.049 (-0.069)
    Player: 42.27% (G:7.76% B:0.18%)
    Opponent: 57.73% (G:13.13% B:0.51%)
    Confidence: ±0.010 (-0.058..-0.039) - [0.0%]

    5. Rollout¹ 10/4 8/4 eq:-0.087 (-0.107)
    Player: 39.23% (G:6.38% B:0.13%)
    Opponent: 60.77% (G:6.99% B:0.18%)
    Confidence: ±0.009 (-0.096..-0.078) - [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=--aB-BC-C--A-A--bccccC----: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 X |
    | O O | | O O X |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X | +---+
    | X | | X X X | | 2 |
    | X X | | X X X O | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 145 O: 119 X-O: 0-0
    Cube: 2, X own cube
    X to play 64
    1. Rollout¹ 13/7 11/7 eq:+0.097
    Player: 46.67% (G:7.31% B:0.18%)
    Opponent: 53.33% (G:8.62% B:0.17%)
    Confidence: ±0.010 (+0.087..+0.106) - [100.0%]

    2. Rollout¹ 21/15 11/7 eq:+0.064 (-0.033)
    Player: 46.17% (G:7.53% B:0.20%)
    Opponent: 53.83% (G:12.04% B:0.36%)
    Confidence: ±0.010 (+0.053..+0.074) - [0.0%]

    3. Rollout¹ 21/11 eq:+0.043 (-0.054)
    Player: 44.14% (G:7.45% B:0.20%)
    Opponent: 55.86% (G:8.11% B:0.25%)
    Confidence: ±0.008 (+0.035..+0.051) - [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
    Wow, I got this right!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    Kudos to me!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to All on Mon Feb 6 05:54:07 2023
    I found my way to the wrong play, making the 4 point, by the esthetic appeal of making the prime.

    By Robertie's (borrowed?) principle of do what's hardest first, you can find your way to leaping with the 6. There are plenty of rolls to make a semi-prime in follow up.

    Bob

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