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41$-44, enlightened data

Posted By: Nack Ballard
Date: Thursday, 20 May 2010, at 7:22 a.m.

In Response To: 41$-44 XG 4 ply RO extended to 46k (neilkaz)

41$-44

Blue played D (best for money)

Blue played P (best at GG)

Here is money data for 41$-44:

Snowie... [D P11] 40k
GnuBG... [P D25] 20k, but [D P11] after Rockwell adj (see notes below)
XG 3-ply [P D12] 36k
XG 3 / 4 [P D16] 31k
XG 4-ply [D P9] 46k

Key: D = Down (with hit assumed) 24/16* 13/9(2), and P = Point (4pt with hit assumed) 24/16* 8/4(2).

David Rockwell did some excellent research and painstaking analysis of Gnu's poor cube action, debunking its rollout result of [P D25] above. From a February e-mail, he summarized:

After 41$-44P- {dance} GNU erroneously doubles and passes. The proper cube action is D/T. This inappropriately raises the equity of P by .0133.

After 41$-44P- {enters with one} GNU erroneously doubles. The proper cube action is ND/T. This inappropriately lowers the equity of P by .0078.

After 41$-44D- {21, 31, 41, 43, 51, 54, 61, 63, 64 or 65} GNU erroneously doubles. The proper cube action is ND/T. This inappropriately lowers the equity of D by .0305.

Reducing the value of P relative to D by .0133 + .0305 - .0078 = .036 adjusts Gnu's rollout result from [P D25] to [D P11]. Amazing!

This cube-action-corrected GnuBG result is identical to Snowie's [D P11] and in close agreement with XG 4-ply's [D P9].

What remains are the strange ones XG 3-ply move 4-ply cube [P D16] and 3-ply 3-ply [P D12]. What's going on there -- any thoughts, Neil? Xavier?

And David, if you feel like doing a similarly astute analysis (for 41$-44D and/or 41$-44P) on XG 3-ply that you did on Gnu, who knows what you might find. I realize you have a lot of competing projects, though.

Finally, it is worth noting that at DMP and GS, the best play is neither of the two diagrammed above; rather Blue should play B (Both, 24/20(2) 13/9(2)), hitting just one checker, as shown below.

Nack

Blue played B (best at DMP and GS)

Messages In This Thread

• 41$-44 XG 4 ply RO extended to 46k
  neilkaz -- Wednesday, 19 May 2010, at 11:35 p.m.
  • 41$-44P-Fan and 41$-44B-Fan
    Paul Weaver -- Thursday, 20 May 2010, at 4:45 a.m.
    • 41$-44D-Fan and 41$-44P-Fan
      Nack Ballard -- Thursday, 20 May 2010, at 7:36 a.m.
      • 41$-44D-Fan and 41$-44P-Fan
        Daniel Murphy -- Thursday, 20 May 2010, at 3:41 p.m.
        • 41$-44D-Fan and 41$-44P-Fan
          Nack Ballard -- Thursday, 20 May 2010, at 3:49 p.m.
  • 41$-44, enlightened data
    Nack Ballard -- Thursday, 20 May 2010, at 7:22 a.m.
    • 41$-44, enlightened data
      David Rockwell -- Thursday, 20 May 2010, at 2:42 p.m.
      • 41$-44, enlightened data
        Nack Ballard -- Sunday, 23 May 2010, at 5:32 a.m.
  • Nactations of 41$-44 — 2012 Update
    Taper_Mike -- Friday, 30 March 2012, at 12:56 a.m.