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  • Early blitz checker play

    From Timothy Chow@21:1/5 to All on Sun Jul 23 09:15:42 2023
    XGID=aBAa--C-C---dD---d-e----B-: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 X |
    | X O | | O X |
    | X O | | O |
    | X O | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | O | | |
    | O X | | X |
    | O X | | X X |
    | O X | | X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 161 X-O: 0-0
    Cube: 1
    X to play 64

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sun Jul 23 13:39:02 2023
    On 7/23/2023 9:15 AM, Timothy Chow wrote:
    XGID=aBAa--C-C---dD---d-e----B-: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              X |
     | X           O    |   | O              X |
     | X           O    |   | O                |
     | X           O    |   | O                |
     |                  |   | O                |
     |                  |BAR|                  |
     |                  | O |                  |
     | O                |   |                  |
     | O           X    |   | X                |
     | O           X    |   | X              X |
     | O           X    |   | X        O  X  X |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 146  O: 161 X-O: 0-0
    Cube: 1
    X to play 64

    Cover the four of course, but only once. No need to bury a third checker
    there.

    And since it's starting to look like a blitz, bring one down instead of
    running the stragglers.

    That leaves 13/7 8/4 or 13/9 6/2?


    The latter looks more flexible since spare and blot are farther away
    from the points we want to make next.

    13/9 6/2.

    --
    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 ah....Clem on Mon Jul 24 07:50:02 2023
    On 7/23/2023 1:39 PM, ah....Clem wrote:
    On 7/23/2023 9:15 AM, Timothy Chow wrote:
    XGID=aBAa--C-C---dD---d-e----B-: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              X | >>   | X           O    |   | O              X | >>   | X           O    |   | O                |
      | X           O    |   | O                |
      |                  |   | O                |
      |                  |BAR|                  |
      |                  | O |                  |
      | O                |   |                  |
      | O           X    |   | X                |
      | O           X    |   | X              X | >>   | O           X    |   | X        O  X  X |
      +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 146  O: 161 X-O: 0-0
    Cube: 1
    X to play 64

    Cover the four of course, but only once. No need to bury a third checker there.

    And since it's starting to look like a blitz, bring one down instead of running the stragglers.

    That leaves 13/7 8/4 or 13/9 6/2?


    The latter looks more flexible since spare and blot are farther away
    from the points we want to make next.

    13/9 6/2.

    13/9 6/2 is illegal, and you probably don't mean 13/7 8/4 since it's the
    2pt that needs covering, not the 4pt.

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Mon Jul 24 13:18:27 2023
    On 7/24/2023 7:50 AM, Timothy Chow wrote:
    On 7/23/2023 1:39 PM, ah....Clem wrote:
    On 7/23/2023 9:15 AM, Timothy Chow wrote:
    XGID=aBAa--C-C---dD---d-e----B-: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              X | >>>   | X           O    |   | O              X | >>>   | X           O    |   | O                |
      | X           O    |   | O                |
      |                  |   | O                |
      |                  |BAR|                  |
      |                  | O |                  |
      | O                |   |                  |
      | O           X    |   | X                |
      | O           X    |   | X              X | >>>   | O           X    |   | X        O  X  X |
      +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 146  O: 161 X-O: 0-0
    Cube: 1
    X to play 64

    Cover the four of course, but only once. No need to bury a third
    checker there.

    And since it's starting to look like a blitz, bring one down instead
    of running the stragglers.

    That leaves 13/7 8/4 or 13/9 6/2?


    The latter looks more flexible since spare and blot are farther away
    from the points we want to make next.

    13/9 6/2.

    13/9 6/2 is illegal, and you probably don't mean 13/7 8/4 since it's the
    2pt that needs covering, not the 4pt.


    Right. It's 13/7 6/2 vs 13/9 8/2. As for which one is better, it's
    probably about shot counting, both O hitting X and also X having better
    rolls.

    I suck at shot counting, so I'll opt for 5&4 to hit the blot if it's
    still there instead of 6&3. No idea if it's right.

    --
    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 Tue Jul 25 08:57:18 2023
    XGID=aBAa--C-C---dD---d-e----B-: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 X |
    | X O | | O X |
    | X O | | O |
    | X O | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | O | | |
    | O X | | X |
    | O X | | X X |
    | O X | | X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 161 X-O: 0-0
    Cube: 1
    X to play 64

    As ah...clem said, the usual approach in a blitz is to favor bringing
    more builders into the zone over moving the back checkers. So I was
    surprised to see that XG strongly favors 24/20 8/2 in this position.
    My best guess as to what's going on is that there's a pretty good
    chance that O will enter and expose another blot in the outfield, and
    24/20 provides good outfield coverage. Also, of course, 24/20 will
    be more constructive if the blitz fails, though I suspect this is a
    secondary consideration and not a primary one.

    1. Rollout¹ 24/20 8/2 eq:+0.450
    Player: 58.42% (G:24.82% B:0.38%)
    Opponent: 41.58% (G:10.41% B:0.47%)
    Confidence: ±0.018 (+0.432..+0.467) - [100.0%]

    2. Rollout¹ 13/9 8/2 eq:+0.376 (-0.074)
    Player: 56.81% (G:26.68% B:0.42%)
    Opponent: 43.19% (G:11.70% B:0.63%)
    Confidence: ±0.013 (+0.364..+0.389) - [0.0%]

    3. Rollout¹ 13/7 6/2 eq:+0.358 (-0.092)
    Player: 56.24% (G:24.34% B:0.33%)
    Opponent: 43.76% (G:11.71% B:0.53%)
    Confidence: ±0.014 (+0.345..+0.372) - [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=aBAa--C-C---bDb--d-e----B-: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 X |
    | X O O | | O X |
    | X O | | O |
    | X O | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | | | |
    | X | | X |
    | O X | | X X |
    | O X | | X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 157 X-O: 0-0
    Cube: 1
    X to play 64

    1. Rollout¹ 13/9 8/2 eq:+0.292
    Player: 54.16% (G:25.78% B:0.44%)
    Opponent: 45.84% (G:12.86% B:0.73%)
    Confidence: ±0.009 (+0.283..+0.301) - [75.7%]

    2. Rollout¹ 24/20 8/2 eq:+0.287 (-0.005)
    Player: 54.91% (G:23.47% B:0.50%)
    Opponent: 45.09% (G:12.10% B:0.54%)
    Confidence: ±0.011 (+0.276..+0.298) - [24.3%]

    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 Stick Rice@21:1/5 to Timothy Chow on Thu Sep 21 10:30:45 2023
    On Tuesday, July 25, 2023 at 8:57:21 AM UTC-4, Timothy Chow wrote:
    XGID=aBAa--C-C---dD---d-e----B-: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 X |
    | X O | | O X |
    | X O | | O |
    | X O | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | O | | |
    | O X | | X |
    | O X | | X X |
    | O X | | X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 161 X-O: 0-0
    Cube: 1
    X to play 64
    As ah...clem said, the usual approach in a blitz is to favor bringing
    more builders into the zone over moving the back checkers. So I was surprised to see that XG strongly favors 24/20 8/2 in this position.
    My best guess as to what's going on is that there's a pretty good
    chance that O will enter and expose another blot in the outfield, and
    24/20 provides good outfield coverage. Also, of course, 24/20 will
    be more constructive if the blitz fails, though I suspect this is a secondary consideration and not a primary one.

    1. Rollout¹ 24/20 8/2 eq:+0.450
    Player: 58.42% (G:24.82% B:0.38%)
    Opponent: 41.58% (G:10.41% B:0.47%)
    Confidence: ±0.018 (+0.432..+0.467) - [100.0%]

    2. Rollout¹ 13/9 8/2 eq:+0.376 (-0.074)
    Player: 56.81% (G:26.68% B:0.42%)
    Opponent: 43.19% (G:11.70% B:0.63%)
    Confidence: ±0.013 (+0.364..+0.389) - [0.0%]

    3. Rollout¹ 13/7 6/2 eq:+0.358 (-0.092)
    Player: 56.24% (G:24.34% B:0.33%)
    Opponent: 43.76% (G:11.71% B:0.53%)
    Confidence: ±0.014 (+0.345..+0.372) - [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=aBAa--C-C---bDb--d-e----B-: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 X |
    | X O O | | O X |
    | X O | | O |
    | X O | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | | | |
    | X | | X |
    | O X | | X X |
    | O X | | X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 157 X-O: 0-0
    Cube: 1
    X to play 64
    1. Rollout¹ 13/9 8/2 eq:+0.292
    Player: 54.16% (G:25.78% B:0.44%)
    Opponent: 45.84% (G:12.86% B:0.73%)
    Confidence: ±0.009 (+0.283..+0.301) - [75.7%]

    2. Rollout¹ 24/20 8/2 eq:+0.287 (-0.005)
    Player: 54.91% (G:23.47% B:0.50%)
    Opponent: 45.09% (G:12.10% B:0.54%)
    Confidence: ±0.011 (+0.276..+0.298) - [24.3%]

    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

    The cube is wicked efficient next turn after the opp's fans if you cover and split whereas if you cover and bring down another builder you've overshot your market by a mile. This isn't how I'd think about it, just thought maybe it was worth mentioning.
    The opponent fans 1/4th (9) of the (36) games. He enters and anchors (thus ending your blitz more or less) in 15 games. If you play 13/9 then he can enter and hit in 6 more games! That's 5/6th of the games that the extra builder down is basically
    worthless. Your biggest issue when he's still in the game is your back checkers. You can rectify that now.

    Stick

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