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54S-21H-31 and 54S-41H-31

Posted By: Nack Ballard
Date: Saturday, 19 June 2010, at 6:01 p.m.

In Response To: More rollouts (Stick)

54S-21H-31: U is best; W is a big mistake

54S-41H-31: W is tied with U

Thanks for the rollouts you didn't want to do, Stick. :)

So, the XG full data we have now for the three relevant plays is

54S-21H-31 [U V9 W56] 25k 6kW
54S-41H-31 [W U3] 15k, and [W U1 V10] 1t (Snw)

Key: U = Up (Bar/21), V = Variant-Up (Bar/22 24/23), W = Wild (Bar/22 6/5).

Error sizes are in thousandths. Before "k" is the number of (full) trials and before "t" is the number of truncated trials (in thousands, rounded down). For example, "[W U1 V10] 1t" means that W is best and U is -.001 after 1000+ truncated trials.

There is a U/W swing of .06 between the two positions. Slotting the 5pt with W (as illustrated in the right-hand diagram below), is profoundly more reasonable when duplicating 4s, and attacking the 9pt blot is (on balance) of added benefit.

Blue played W, a big mistake

Blue played W, a strong play

If, in the second position, W had been a clear choice over U, the position pair would have found its way into Backgammon Openings (Chapter 3, Slotting division).

Nack

Messages In This Thread

• 3rd roll decison
  Chuck Bower -- Friday, 18 June 2010, at 12:01 a.m.
  • 54S-21H-31?
    Stick -- Friday, 18 June 2010, at 12:20 a.m.
    • 54S-21H-31?
      Leonardo Jerkovic -- Friday, 18 June 2010, at 1:47 a.m.
  • 3rd roll decison
    John O'Hagan -- Friday, 18 June 2010, at 1:31 a.m.
  • 54S-21H-31 -- warning, bot content
    Nack Ballard -- Friday, 18 June 2010, at 3:35 a.m.
  • Rollout
    Stick -- Friday, 18 June 2010, at 6:15 p.m.
    • 54S-21H-31 and 54S-41H-31
      Nack Ballard -- Saturday, 19 June 2010, at 5:18 a.m.
      • 54S-21H-31 and 54S-41H-31
        Stick -- Saturday, 19 June 2010, at 5:56 a.m.
      • More rollouts
        Stick -- Saturday, 19 June 2010, at 4:26 p.m.
        • 54S-21H-31 and 54S-41H-31
          Nack Ballard -- Saturday, 19 June 2010, at 6:01 p.m.
    • Longer Rollout
      Chuck Bower -- Saturday, 19 June 2010, at 2:44 p.m.
      • Role of truncs, variance of full rollouts
        Nack Ballard -- Saturday, 19 June 2010, at 5:14 p.m.
        • Role of truncs, variance of full rollouts
          Stick -- Saturday, 19 June 2010, at 5:22 p.m.
        • Role of truncs, variance of full rollouts
          Daniel Murphy -- Saturday, 19 June 2010, at 5:56 p.m.
        • Truncated rollouts at the start of a game
          Tom Keith -- Sunday, 20 June 2010, at 2:22 p.m.
        • Rollout eXtension
          Stick -- Sunday, 20 June 2010, at 9:55 p.m.
          • Rollout eXtension
            Nack Ballard -- Sunday, 20 June 2010, at 11:09 p.m.
            • Rollout eXtension
              Stick -- Sunday, 20 June 2010, at 11:14 p.m.
  • 40k trial rollout result
    Chuck Bower -- Monday, 21 June 2010, at 12:03 p.m.