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Snowie rollout

Posted By: Nack Ballard
Date: Wednesday, 28 September 2011, at 1:05 a.m.

In Response To: Snowie rollout (Nack Ballard)

Busted R4

I haven’t yet figured out how to include normal-looking text (non-centered on a white background) in the same post as a Snowie rollout, so I posted the latter separately.

This turns out to be a position for which using a live cube makes a big difference in the rollout result. Our original Snowie result (documented before the underlying file was lost) was [V B6 @44] ~10*2, Janowski-cube-adjusted (where V = 24/21(3) 21/18, B = 24/21(2) 13/10(2), @ = 24/18(2)). No live cube was used.

Consistent with that, the new Snowie rollout result I just posted is [V B9 @43] ~10, Janowski-cube-adjusted. However, if you know how to read between the lines, you’ll see that the live cube result is [@ V1 B1] ~10. That live cube result is similar to the GnuBG and XG live cube rollout results recently posted.

At the time (2006), we confirmed that @ was also not a competitive play in a money rollout done on GnuBG (by Stick). However, unbeknownst to Stick, Paul and myself, the GnuBG version 14.3 devel was corrupt, and just happened to downgrade @ for money, while showing V and/or B to be the best play, yet at the same time the rollout results at the other three scores were apparently not corrupt. More details can be read here. In short, the circumstances leading to this position being represented in publication as an R4 were the consequence of an unusual, unlucky parlay.

The happy ending is that adjusting the placement of two spares gives us this legitimate R4.

Nack

Messages In This Thread

• Four-score position from "Backgammon Openings"
  Timothy Chow -- Monday, 19 September 2011, at 5:02 p.m.
  • Four-score position from "Backgammon Openings"
    Stick -- Monday, 19 September 2011, at 5:19 p.m.
    • Four-score position from "Backgammon Openings"
      Timothy Chow -- Monday, 19 September 2011, at 11:28 p.m.
  • Longer Money Rollout - Cube Centered
    Stick -- Tuesday, 20 September 2011, at 7:39 a.m.
    • A special request for Stick and other rollers on BGO
      Taper_Mike -- Wednesday, 21 September 2011, at 6:50 a.m.
      • A special request for Stick and other rollers on BGO
        Nack Ballard -- Wednesday, 21 September 2011, at 3:03 p.m.
        • A special request for Stick and other rollers on BGO
          Taper_Mike -- Wednesday, 21 September 2011, at 7:32 p.m.
      • A special request for Stick and other rollers on BGO
        Timothy Chow -- Wednesday, 21 September 2011, at 3:15 p.m.
        • A special request for Stick and other rollers on BGO
          Stick -- Wednesday, 21 September 2011, at 3:20 p.m.
          • A special request for Stick and other rollers on BGO
            Taper_Mike -- Wednesday, 21 September 2011, at 6:48 p.m.
          • A special request for Stick and other rollers on BGO
            Timothy Chow -- Thursday, 22 September 2011, at 1:34 a.m.
            • A special request for Stick and other rollers on BGO
              eXtreme Gammon -- Thursday, 22 September 2011, at 12:29 p.m.
              • A special request for Stick and other rollers on BGO
                Taper_Mike -- Friday, 23 September 2011, at 1:06 a.m.
    • GNU Money Rollout - Cube Centered
      Stick -- Thursday, 22 September 2011, at 12:29 p.m.
  • Four-score position from "Backgammon Openings"
    Nack Ballard -- Wednesday, 21 September 2011, at 12:36 a.m.
    • R4 with double 3s, now found
      Nack Ballard -- Friday, 23 September 2011, at 7:00 p.m.
      • R4 with double 3s, now found
        Nack Ballard -- Saturday, 24 September 2011, at 3:12 p.m.
    • Snowie rollout
      Nack Ballard -- Wednesday, 28 September 2011, at 12:38 a.m.
      • Snowie rollout
        Nack Ballard -- Wednesday, 28 September 2011, at 1:05 a.m.