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  • I should have made a mistake here

    From [email protected]@21:1/5 to All on Sun Sep 4 01:44:58 2022
    Here, I took but I regretted it, and I was anticipating a horrendous PR.
    As it happens, I played the game perfectly as far as I can tell without rollouts. (My PR was less than 1).
    The opponent's blitz is formidable, and I think most strong players
    would drop here, and that, given that humans can't evaluate
    these positions exactly, a drop is the practical choice.
    So, a correct take, but not a well-informed one.
    My game would improve, I'm sure, if I dropped this type of position.

    Paul

    XGID=---Bb-EBBa---C-a-bacc-b--A:0:0:-1:00:0:0:3:0:10
    X:eXtremeGammon O:Daniel

    Score is X:0 O:0. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | O O | | O X O |
    | | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | | | |
    | O | | X X |
    | O X | | X X X |
    | O X X X | | X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 130 O: 130 X-O: 0-0
    Cube: 1
    X on roll, cube action

    Analyzed in 4-ply
    Player Winning Chances: 68.81% (G:27.40% B:0.39%)
    Opponent Winning Chances: 31.19% (G:5.51% B:0.19%)

    Cubeless Equities: No Double=+0.597, Double=+1.208

    Cubeful Equities:
    No double: +0.767 (-0.221)
    Double/Take: +0.988
    Double/Pass: +1.000 (+0.012)

    Best Cube action: Double / Take

    eXtreme Gammon Version: 2.10

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to [email protected] on Sun Sep 4 09:37:44 2022
    On 9/4/2022 4:44 AM, [email protected] wrote:
    Here, I took but I regretted it, and I was anticipating a horrendous PR.
    As it happens, I played the game perfectly as far as I can tell without rollouts. (My PR was less than 1).
    The opponent's blitz is formidable, and I think most strong players
    would drop here, and that, given that humans can't evaluate
    these positions exactly, a drop is the practical choice.

    I would probably have dropped, but it's worth noting some of the
    differences between this position and your previous one.

    1. O has made her bar point and 3pt. This is the most important
    difference IMO. It gives O much better defensive chances.

    2. The race is even here, whereas in the previous position the
    taker was 12 pips down. When the blitzee has just one checker
    back, the slime vig of escaping the last checker and winning the
    race is important, and by extension the pip count is important.

    3. X's board is slightly weaker here, with the 3pt made instead
    of the 4pt.

    4. X is anchored here but not in the previous position. Being anchored
    is usually a big plus, but in the previous position, the taker's
    position was so weak that being unanchored was not really a liability.

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah...Clem@21:1/5 to [email protected] on Mon Sep 5 09:40:25 2022
    On 9/4/2022 4:44 AM, [email protected] wrote:
    Here, I took but I regretted it...

    XGID=---Bb-EBBa---C-a-bacc-b--A:0:0:-1:00:0:0:3:0:10
    X:eXtremeGammon O:Daniel

    Score is X:0 O:0. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | O O | | O X O |
    | | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | | | |
    | O | | X X |
    | O X | | X X X |
    | O X X X | | X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 130 O: 130 X-O: 0-0
    Cube: 1
    X on roll, cube action

    PRAT would imply D/T. Yeah, this is pretty simplistic, but it's
    interesting how often it works.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From [email protected]@21:1/5 to ah...Clem on Mon Sep 5 12:56:11 2022
    On Monday, September 5, 2022 at 2:40:28 PM UTC+1, ah...Clem wrote:
    On 9/4/2022 4:44 AM, [email protected] wrote:
    Here, I took but I regretted it... XGID=---Bb-EBBa---C-a-bacc-b--A:0:0:-1:00:0:0:3:0:10
    X:eXtremeGammon O:Daniel

    Score is X:0 O:0. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O O | | O X O |
    | O O | | O X O |
    | | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | O | |
    | | | |
    | O | | X X |
    | O X | | X X X |
    | O X X X | | X X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 130 O: 130 X-O: 0-0
    Cube: 1
    X on roll, cube action
    PRAT would imply D/T. Yeah, this is pretty simplistic, but it's
    interesting how often it works.

    Without any evidence whatsoever, I'll hypothesise that it's a drop in the following sense.
    Suppose you borrow Tim Chow's shoes, and do a large number of variantizations, where the changes to the position are apparently very slight.
    And suppose you agree to make the same drop/take decision with all variantizations.
    (The double is absolutely clear.)
    Then I think you might lose less equity by dropping the class of variantizations rather than
    taking them.
    Somehow, a drop seems like a practical choice that a strong player would normally make,
    even though XG finds a take.

    Paul

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