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  • Another TG problem

    From pepstein5@gmail.com@21:1/5 to All on Sat Aug 7 12:56:29 2021
    With 3 on the bar, XG can't take this.
    But is this TG?

    Paul

    XGID=cB-BBBB-A---b-b----bbbbBB-:2:1:1:00:0:8:3:0:X:Daniel O:eXtremeGammon
    10

    Score is X:0 O:8. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O X X |
    | O | | O O O O X X |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | | +---+
    | O | | X X X X X | | 4 |
    | O X | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 159 X-O: 0-8
    Cube: 4, X own cube
    X on roll, cube action

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to peps...@gmail.com on Sun Aug 8 21:21:40 2021
    On 8/7/2021 3:56 PM, peps...@gmail.com wrote:
    With 3 on the bar, XG can't take this.
    But is this TG?

    Paul

    XGID=cB-BBBB-A---b-b----bbbbBB-:2:1:1:00:0:8:3:0:X:Daniel O:eXtremeGammon 10

    Score is X:0 O:8. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O X X |
    | O | | O O O O X X |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | | +---+
    | O | | X X X X X | | 4 |
    | O X | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 159 X-O: 0-8
    Cube: 4, X own cube
    X on roll, cube action

    If X doesn't roll an immediate 5 or 6 then he's likely to crunch and be
    in big trouble. This looks like a clear ND/T to me. Maybe it's close
    to a beaver?

    ---
    Tim Chow

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  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Mon Aug 9 00:44:23 2021
    On Monday, August 9, 2021 at 2:21:43 AM UTC+1, Tim Chow wrote:
    On 8/7/2021 3:56 PM, peps...@gmail.com wrote:
    With 3 on the bar, XG can't take this.
    But is this TG?

    Paul

    XGID=cB-BBBB-A---b-b----bbbbBB-:2:1:1:00:0:8:3:0:X:Daniel O:eXtremeGammon 10

    Score is X:0 O:8. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O X X |
    | O | | O O O O X X |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | | +---+
    | O | | X X X X X | | 4 |
    | O X | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 159 X-O: 0-8
    Cube: 4, X own cube
    X on roll, cube action
    If X doesn't roll an immediate 5 or 6 then he's likely to crunch and be
    in big trouble. This looks like a clear ND/T to me. Maybe it's close
    to a beaver?

    It seems like I set the toughest quizzes ever.
    It's a perfectly good double (fortunately, because I did double).
    Let's define a crunching roll rigorously. I think that would be a roll where the optimal play
    has the result that [(there exists an integer 1 <= k <= 5 such that the
    number of checkers on our lowest k points is >= 2 * k + 1) and our inner board is not
    closed]. There actually aren't so many.

    Paul

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 59.25% (G:42.74% B:1.46%)
    Opponent Winning Chances: 40.75% (G:13.59% B:0.82%)
    Redouble/Take
    Player Winning Chances: 59.94% (G:43.13% B:1.31%)
    Opponent Winning Chances: 40.06% (G:13.36% B:0.80%)

    Cubeless Equities: No Double=+0.483, Double=+1.003

    Cubeful Equities:
    No redouble: +0.657 (-0.061)
    Redouble/Take: +0.718
    Redouble/Pass: +1.000 (+0.282)

    Best Cube action: Redouble / Take

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.013 (+0.643..+0.670)
    Confidence Double: ± 0.021 (+0.696..+0.739)

    Double Decision confidence: 100.0%
    Take Decision confidence: 100.0%

    Duration: 32 minutes 08 seconds

    eXtreme Gammon Version: 2.10

    --- SoupGate-Win32 v1.05
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  • From J R@21:1/5 to Tim Chow on Thu Aug 19 03:03:26 2021
    On Sunday, August 8, 2021 at 9:21:43 PM UTC-4, Tim Chow wrote:
    On 8/7/2021 3:56 PM, peps...@gmail.com wrote:
    With 3 on the bar, XG can't take this.
    But is this TG?

    Paul

    XGID=cB-BBBB-A---b-b----bbbbBB-:2:1:1:00:0:8:3:0:X:Daniel O:eXtremeGammon 10

    Score is X:0 O:8. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O X X |
    | O | | O O O O X X |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | | +---+
    | O | | X X X X X | | 4 |
    | O X | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 159 X-O: 0-8
    Cube: 4, X own cube
    X on roll, cube action
    If X doesn't roll an immediate 5 or 6 then he's likely to crunch and be
    in big trouble. This looks like a clear ND/T to me. Maybe it's close
    to a beaver?

    ---
    Tim Chow

    Do you really look at this position and not have a huge preference for which side you'd rather be?

    Stick

    --- SoupGate-Win32 v1.05
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  • From pepstein5@gmail.com@21:1/5 to J R on Thu Aug 19 04:33:01 2021
    On Thursday, August 19, 2021 at 11:03:27 AM UTC+1, J R wrote:
    On Sunday, August 8, 2021 at 9:21:43 PM UTC-4, Tim Chow wrote:
    On 8/7/2021 3:56 PM, peps...@gmail.com wrote:
    With 3 on the bar, XG can't take this.
    But is this TG?

    Paul

    XGID=cB-BBBB-A---b-b----bbbbBB-:2:1:1:00:0:8:3:0:X:Daniel O:eXtremeGammon 10

    Score is X:0 O:8. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O X X |
    | O | | O O O O X X |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | | +---+
    | O | | X X X X X | | 4 |
    | O X | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 159 X-O: 0-8
    Cube: 4, X own cube
    X on roll, cube action
    If X doesn't roll an immediate 5 or 6 then he's likely to crunch and be
    in big trouble. This looks like a clear ND/T to me. Maybe it's close
    to a beaver?

    ---
    Tim Chow
    Do you really look at this position and not have a huge preference for which side you'd rather be?

    Stick
    I would think that he obviously doesn't because he suggests "close to a beaver". A beaver would mean he prefers O --- "close to a beaver" means he doesn't have much of a preference.
    AFAIK, no one who uses this forum is as good as you are.

    Paul

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  • From Timothy Chow@21:1/5 to peps...@gmail.com on Thu Aug 19 08:37:07 2021
    On 8/19/2021 7:33 AM, peps...@gmail.com wrote:
    AFAIK, no one who uses this forum is as good as you are.

    Paul, do you know this one?

    Everybody loves my baby, but my baby loves nobody but me.

    Prove that I am my baby.

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
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  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Sat Aug 21 14:21:22 2021
    On Monday, August 9, 2021 at 2:21:43 AM UTC+1, Tim Chow wrote:
    On 8/7/2021 3:56 PM, peps...@gmail.com wrote:
    With 3 on the bar, XG can't take this.
    But is this TG?

    Paul

    XGID=cB-BBBB-A---b-b----bbbbBB-:2:1:1:00:0:8:3:0:X:Daniel O:eXtremeGammon 10

    Score is X:0 O:8. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O | | O O O O X X |
    | O | | O O O O X X |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | | +---+
    | O | | X X X X X | | 4 |
    | O X | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 140 O: 159 X-O: 0-8
    Cube: 4, X own cube
    X on roll, cube action
    If X doesn't roll an immediate 5 or 6 then he's likely to crunch and be
    in big trouble. This looks like a clear ND/T to me. Maybe it's close
    to a beaver?

    Curiously, I got quite a similar position in a later game. I wonder if you would have misassessed this.
    I can't be bothered to do a full rollout but I will post the analysis.
    The partial rollout doesn't rate X's position quite as high as the analysis does.
    It's actually a monster double which is fairly close to a pass.
    I didn't even consider doubling, because of all the work I need to do to release my back checkers.

    Paul

    XGID=cBBCB-C-----b----bbbbBbA--:1:1:1:00:15:1X:Daniel O:eXtremeGammon 4:3:0:10

    Score is X:15 O:14. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O X O X |
    | O O | | O O X O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | X X | +---+
    | O | | X X X X X | | 2 |
    | O | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 106 O: 159 X-O: 15-14
    Cube: 2, X own cube
    X on roll, cube action

    Analyzed in XG Roller+
    Player Winning Chances: 61.37% (G:45.83% B:0.87%)
    Opponent Winning Chances: 38.63% (G:8.04% B:0.34%)

    Cubeless Equities: No Double=+0.611, Double=+1.251

    Cubeful Equities:
    No redouble: +0.767 (-0.204)
    Redouble/Take: +0.971
    Redouble/Pass: +1.000 (+0.029)

    Best Cube action: Redouble / Take

    eXtreme Gammon Version: 2.10

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to peps...@gmail.com on Mon Aug 23 23:51:42 2021
    On 8/21/2021 5:21 PM, peps...@gmail.com wrote:
    XGID=cBBCB-C-----b----bbbbBbA--:1:1:1:00:15:1X:Daniel O:eXtremeGammon 4:3:0:10

    Score is X:15 O:14. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O | | O O X O X |
    | O O | | O O X O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | O | |
    | | O | |
    | | O | X X | +---+
    | O | | X X X X X | | 2 |
    | O | | X X X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 106 O: 159 X-O: 15-14
    Cube: 2, X own cube
    X on roll, cube action

    Analyzed in XG Roller+
    Player Winning Chances: 61.37% (G:45.83% B:0.87%)
    Opponent Winning Chances: 38.63% (G:8.04% B:0.34%)

    Cubeless Equities: No Double=+0.611, Double=+1.251

    Cubeful Equities:
    No redouble: +0.767 (-0.204)
    Redouble/Take: +0.971
    Redouble/Pass: +1.000 (+0.029)

    Best Cube action: Redouble / Take

    eXtreme Gammon Version: 2.10


    I wouldn't have expected this to be so close to a pass but I would
    have doubled I think. I see a big difference in that O's board is
    not as strong and X has a high anchor, plus X has only 3 checkers
    back and not 4. So X is not in as much trouble if he doesn't get
    out right away, and by the same token he's doing much better if he
    does get a checker out.

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
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  • From pepstein5@gmail.com@21:1/5 to All on Fri Mar 4 11:34:31 2022
    XGID=-LB--aa-b----A-ab-bbbb----:3:1:1:00:10:3:3:0:10
    X:Daniel O:eXtremeGammon


    Score is X:10 O:3. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O O | | O O O |
    | O O | | O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | 12 |
    | | | X |
    | | | X | +---+
    | O | | X X | | 8 |
    | O | | O O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 29 O: 145 X-O: 10-3
    Cube: 8, X own cube
    X on roll, cube action

    Clearly a huge pass, but is X too good to double?

    Paul

    --- SoupGate-Win32 v1.05
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  • From Timothy Chow@21:1/5 to peps...@gmail.com on Sat Mar 5 07:23:41 2022
    On 3/4/2022 2:34 PM, peps...@gmail.com wrote:
    XGID=-LB--aa-b----A-ab-bbbb----:3:1:1:00:10:3:3:0:10
    X:Daniel O:eXtremeGammon


    Score is X:10 O:3. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O O | | O O O |
    | O O | | O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | 12 |
    | | | X |
    | | | X | +---+
    | O | | X X | | 8 |
    | O | | O O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 29 O: 145 X-O: 10-3
    Cube: 8, X own cube
    X on roll, cube action

    Clearly a huge pass, but is X too good to double?

    There are way too many ways for X to regain his market here
    so I don't think this is too good. In fact, I'd be tempted
    to take this as O, but it's probably a pass.

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Sun Mar 6 10:00:26 2022
    On Saturday, March 5, 2022 at 12:23:44 PM UTC, Tim Chow wrote:
    On 3/4/2022 2:34 PM, peps...@gmail.com wrote:
    XGID=-LB--aa-b----A-ab-bbbb----:3:1:1:00:10:3:3:0:10
    X:Daniel O:eXtremeGammon


    Score is X:10 O:3. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O O | | O O O |
    | O O | | O O O |
    | | | |
    | | | |
    | | | |
    | |BAR| |
    | | | 12 |
    | | | X |
    | | | X | +---+
    | O | | X X | | 8 |
    | O | | O O X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 29 O: 145 X-O: 10-3
    Cube: 8, X own cube
    X on roll, cube action

    Clearly a huge pass, but is X too good to double?
    There are way too many ways for X to regain his market here
    so I don't think this is too good. In fact, I'd be tempted
    to take this as O, but it's probably a pass.

    ---
    Tim Chow

    You're basically right on this. It's extremely marginal between a take and a pass.
    Nothing wrong with taking. I would take OTB.
    I think there's potentially a lot of skill left in the position if the roller doesn't roll home.
    So the practical play is probably pass if you're the weaker player, take if you're the stronger player.

    Paul

    Analyzed in Rollout
    No redouble
    Player Winning Chances: 60.01% (G:48.24% B:0.00%)
    Opponent Winning Chances: 39.99% (G:3.88% B:0.09%)
    Redouble/Take
    Player Winning Chances: 60.51% (G:48.40% B:0.00%)
    Opponent Winning Chances: 39.49% (G:3.79% B:0.08%)

    Cubeless Equities: No Double=+0.643, Double=+1.311

    Cubeful Equities:
    No redouble: +0.655 (-0.345)
    Redouble/Take: +1.001 (+0.001)
    Redouble/Pass: +1.000

    Best Cube action: Redouble / Pass

    Rollout:
    1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller
    Confidence No Double: ± 0.005 (+0.650..+0.661)
    Confidence Double: ± 0.016 (+0.985..+1.017)

    Double Decision confidence: 100.0%
    Take Decision confidence: 55.7%

    Duration: 10 minutes 49 seconds

    eXtreme Gammon Version: 2.10

    --- SoupGate-Win32 v1.05
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  • From Axel Reichert@21:1/5 to peps...@gmail.com on Sun Mar 6 22:06:40 2022
    "peps...@gmail.com" <pepstein5@gmail.com> writes:

    It's extremely marginal between a take and a pass. Nothing wrong with taking. I would take OTB.

    I am a big fan of Trice here: "If in doubt [whether too good], double:
    You will get terrible takes." I will happily apply this heuristic up to,
    say, an (estimated) equity of 1.1. The non-experts (including me) in our
    club will take these positions way too often to render my double wrong.

    Best regards

    Axel

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  • From pepstein5@gmail.com@21:1/5 to Axel Reichert on Sun Mar 6 13:16:32 2022
    On Sunday, March 6, 2022 at 9:06:42 PM UTC, Axel Reichert wrote:
    "peps...@gmail.com" <peps...@gmail.com> writes:

    It's extremely marginal between a take and a pass. Nothing wrong with taking. I would take OTB.
    I am a big fan of Trice here: "If in doubt [whether too good], double:
    You will get terrible takes." I will happily apply this heuristic up to,
    say, an (estimated) equity of 1.1. The non-experts (including me) in our
    club will take these positions way too often to render my double wrong.

    Best regards

    Axel

    Ok, but this is a take/pass problem, not at all a TG problem.
    Holding here is worse than a 0.3 error. It's a spectacularly bad hold.
    I pretended it was a TG problem to try and fool Tim. (It didn't work.)

    Paul

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