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Rollout Result and Commentary

Posted By: Paul Weaver
Date: Friday, 11 February 2011, at 4:03 a.m.

In Response To: 65R-65R-65R-44P-51 (Paul Weaver)

I rolled out the position 5184 times on XG but lost the file. The margin was 13/7 best by 0.023 over 13/8 6/5. [D $23] (The XG+ eval is posted below.) Over the board, I quickly played 13/8 6/5 and I was surprised when the XG analysis favored 13/7. I am suggesting three reasons that slotting the 7pt is better than slotting the 5pt.

(1) As some people have already stated, White, if missed, will have fewer repeaters on his next shake after 13/7 than after 13/8 6/5.

(2) If Black hits after White plays 13/7, White gets more potent return shots. In particular, If Black hits with 61 51 42, White gets 17 return shots on his 7pt. If Black hits after White plays 13/8 6/5, White's return shots are less damaging because they will almost be loose hits on his 5pt instead of safer hits in the outfield.

(3) Finally, there is a subtle form of duplication going on here. White has escaped both back checkers and White has escaped one. This position is very sensitive to the race. Black's 15 4s that hit have an average pip value of 7.3. Black's 17 6s that hit have an average pip value of 9.3. The 6s, in general, are better than the 4s, because they are bigger numbers. By giving Black 6s to hit instead of 4s, White duplicates some of Black's larger numbers. On the other hand, if White gives Black 4s to hit, then Black hits with smaller numbers while 6s are good for racing.

	is Player 2 score: 0 pip: 140 Money session Jacoby Beaver pip: 145 score: 0 is Player 1
XGID=-a----E-C---dG---c-eb-----:0:0:1:51:0:0:3:0:10
to play 51

1.	XG Roller+	13/7	eq: -0.372
	Player: Opponent: 40.18% (G:3.59% B:0.10%) 59.82% (G:10.27% B:0.17%)
2.	XG Roller+	13/8 6/5	eq: -0.389 (-0.018)
	Player: Opponent: 40.21% (G:3.81% B:0.10%) 59.79% (G:11.39% B:0.20%)

eXtreme Gammon Version: 1.21

Messages In This Thread

• 65R-65R-65R-44P-51
  Paul Weaver -- Wednesday, 9 February 2011, at 9:24 p.m.
  • 65R-65R-65R-44P-51
    David Rockwell -- Wednesday, 9 February 2011, at 11:23 p.m.
  • 65R-65R-65R-44P-51
    Nack Ballard -- Wednesday, 9 February 2011, at 11:25 p.m.
    • 65R-65R-65R-44P-51
      Dmitriy Obukhov -- Thursday, 10 February 2011, at 11:14 p.m.
      • The "5pt or bar" position
        Nack Ballard -- Thursday, 10 February 2011, at 11:40 p.m.
        • The "5pt or bar" position
          Timothy Chow -- Friday, 11 February 2011, at 12:01 a.m.
  • 65R-65R-65R-44P-51
    neilkaz -- Wednesday, 9 February 2011, at 11:35 p.m.
  • 65R-65R-65R-44P-51
    Timothy Chow -- Thursday, 10 February 2011, at 1:14 a.m.
  • 65R-65R-65R-44P-51
    Casper van der Tak -- Thursday, 10 February 2011, at 9:13 a.m.
  • 65R-65R-65R-44P-51
    Stick -- Thursday, 10 February 2011, at 2:05 p.m.
  • Rollout Result and Commentary
    Paul Weaver -- Friday, 11 February 2011, at 4:03 a.m.