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  • Not quite a pure race

    From Timothy Chow@21:1/5 to All on Mon Apr 17 09:23:59 2023
    XGID=-BCBCC------bbB-----bbbcb-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O O |
    | O X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X X |
    | O | | X X X X X |
    | O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to Timothy Chow on Mon Apr 17 09:40:23 2023
    On Monday, April 17, 2023 at 9:24:02 AM UTC-4, Timothy Chow wrote:
    XGID=-BCBCC------bbB-----bbbcb-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O O |
    | O X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X X |
    | O | | X X X X X |
    | O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    ---
    Tim Chow
    Based on the race O is 5 pips short of a take, maybe a little more than that with more checkers out and crossovers. So she needs to find about 5-7% wins elsewhere. X leaves a shot with 62 and 52. With that, O has 20 shots. That comes out to 6%. Maybe I'm
    missing something, but it's gotta be real close on the take/pass side.
    Bob

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Timothy Chow on Mon Apr 17 12:46:54 2023
    On Monday, April 17, 2023 at 2:24:02 PM UTC+1, Timothy Chow wrote:
    XGID=-BCBCC------bbB-----bbbcb-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O O |
    | O X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X X |
    | O | | X X X X X |
    | O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    ---
    Tim Chow
    Not much to add to the other analysis but I think it's a very easy take.
    Also, a double.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Axel Reichert@21:1/5 to Timothy Chow on Mon Apr 17 21:20:52 2023
    Timothy Chow <tchow12000@yahoo.com> writes:

    XGID=-BCBCC------bbB-----bbbcb-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O O |
    | O X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X X |
    | O | | X X X X X |
    | O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    Nice partitioning of the rolls here:

    - Everything with both dice >= 3 loses the market by a mile. That is 16
    rolls.
    - 51, 52, 61, 62 are terrible, but it will still be a take if she
    redoubles. That is 8 rolls.
    - The rest forces us to waste some pips, but it is no big deal. We might
    even get a shot (losing the market as well, if we hold the cube
    now). That is 12 rolls.

    Strong double, close take.

    Best regards

    Axel

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Wed Apr 19 08:25:42 2023
    XGID=-BCBCC------bbB-----bbbcb-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O O |
    | O X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X X |
    | O | | X X X X X |
    | O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    If this were a pure race, it would be a massive pass (see the
    variant for example). But of course, it's not a pure race. Eight
    rolls (61 62 51 52) blot immediately and give O 20 rolls to hit.
    According to XG, it's a big double and a big take.

    Analyzed in Rollout
    No double
    Player Winning Chances: 75.27% (G:0.55% B:0.01%)
    Opponent Winning Chances: 24.73% (G:0.28% B:0.00%)
    Double/Take
    Player Winning Chances: 75.28% (G:0.50% B:0.01%)
    Opponent Winning Chances: 24.72% (G:0.27% B:0.00%)

    Cubeful Equities:
    No double: +0.657 (-0.178)
    Double/Take: +0.836
    Double/Pass: +1.000 (+0.164)

    Best Cube action: Double / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.006 (+0.651..+0.664)
    Confidence Double: ± 0.009 (+0.827..+0.844)

    eXtreme Gammon Version: 2.19.211.pre-release

    -------
    Variant
    -------

    XGID=-BBBCCA-----Bbb----abbbbb-:0:0:1:00:0:0:0:0:10

    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 O O O |
    | O O | | O O O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X |
    | X | | X X X X X |
    | X | | X X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    Analyzed in Rollout
    No double
    Player Winning Chances: 86.31% (G:0.00% B:0.00%)
    Opponent Winning Chances: 13.69% (G:0.00% B:0.00%)
    Double/Take
    Player Winning Chances: 86.24% (G:0.00% B:0.00%)
    Opponent Winning Chances: 13.76% (G:0.00% B:0.00%)

    Cubeful Equities:
    No double: +0.949 (-0.051)
    Double/Take: +1.373 (+0.373)
    Double/Pass: +1.000

    Best Cube action: Double / Pass

    Rollout:
    1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.001 (+0.947..+0.950)
    Confidence Double: ± 0.003 (+1.370..+1.376)

    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 Robert Zimmerman on Thu Apr 20 01:16:07 2023
    On Monday, April 17, 2023 at 5:40:24 PM UTC+1, Robert Zimmerman wrote:
    On Monday, April 17, 2023 at 9:24:02 AM UTC-4, Timothy Chow wrote:
    XGID=-BCBCC------bbB-----bbbcb-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O O |
    | O X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X X |
    | O | | X X X X X |
    | O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    ---
    Tim Chow
    Based on the race O is 5 pips short of a take, maybe a little more than that with more checkers out and crossovers. So she needs to find about 5-7% wins elsewhere. X leaves a shot with 62 and 52. With that, O has 20 shots. That comes out to 6%. Maybe I'
    m missing something, but it's gotta be real close on the take/pass side.
    Bob

    Assuming "real close on the take pass side" means that the position is worth at least 0.95 to the favourite,
    the "something" that you're missing is worth slightly more than 0.1

    It's less similar to a race than you present, and there are more blotting numbers than you state.
    Very importantly, the underdog's threats will repeat if the favourite doesn't roll one of the 16/36
    numbers that break contact.

    There's a neat symmetry in that the errors from holding and passing match each other quite closely.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Robert Zimmerman@21:1/5 to peps...@gmail.com on Thu Apr 20 07:24:29 2023
    On Thursday, April 20, 2023 at 4:16:08 AM UTC-4, peps...@gmail.com wrote:
    On Monday, April 17, 2023 at 5:40:24 PM UTC+1, Robert Zimmerman wrote:
    On Monday, April 17, 2023 at 9:24:02 AM UTC-4, Timothy Chow wrote:
    XGID=-BCBCC------bbB-----bbbcb-:0:0:1:00:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O X | | O O O O O |
    | O X | | O O O O O |
    | | | O |
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X X X |
    | O | | X X X X X |
    | O | | X X X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 69 O: 82 X-O: 0-0
    Cube: 1
    X on roll, cube action

    ---
    Tim Chow
    Based on the race O is 5 pips short of a take, maybe a little more than that with more checkers out and crossovers. So she needs to find about 5-7% wins elsewhere. X leaves a shot with 62 and 52. With that, O has 20 shots. That comes out to 6%. Maybe
    I'm missing something, but it's gotta be real close on the take/pass side.
    Bob
    Assuming "real close on the take pass side" means that the position is worth at least 0.95 to the favourite,
    the "something" that you're missing is worth slightly more than 0.1

    It's less similar to a race than you present, and there are more blotting numbers than you state.
    Very importantly, the underdog's threats will repeat if the favourite doesn't roll one of the 16/36
    numbers that break contact.

    There's a neat symmetry in that the errors from holding and passing match each other quite closely.

    Paul
    Good points. Thanks, Paul.
    Missing 4 blotting numbers is no small matter. Not such a close decision... Those neurofibrillary tangles are really taking their toll. (JK!).
    Bob

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