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LV Finals Play #1 ROLLOUT

Posted By: Matt Cohn-Geier
Date: Thursday, 4 December 2008, at 4:00 a.m.

In Response To: LV Finals Play #1 (Matt Cohn-Geier)

Sam is basically right here.

White should run after either play if he rolls a 6. There are 5 numbers after either play where he should stick around: after 2/1*, it's 33, 23, and 42; after 3/2, it's 11, 31, and 41. If White sticks around, I have 5 numbers to win a BG after 3/2 vs. only 4 to win a BG after 2/1*. However, I have 20 numbers that leave a shot after 3/2, vs. only 10 after 2/1*. So 2/1* is significantly safer, and shot numbers that allow White to save the G / possibly win will almost always outweigh the backgammons. So I should play 2/1*, right?

The reason why 3/2 is technically better here is because even though 2/1* is better in the variation where I don't get immediately hit, 3/2 is better when I do get hit since the two checkers are closer to home. I didn't think it would be such a big deal since White has made his ace point and his 6 point is open, so he is very unlikely to pick up a second checker. However that is probably the swing when White opens his board during the bearoff.

Also, 3/2 gives him some (relatively) tough decisions, everything is trivial after 2/1*. So if there was some chance that Stacy would misplay the position after 3/2 it is probably even better practically.

The score (after 11 games) is: Stacy Turner 10, Matt Cohn-Geier 6 (match to 15 points)

Move number 58: Matt Cohn-Geier to play 51

Stacy Turner	102
Matt Cohn-Geier	11
Position ID: 27ZAISA6AAAAAA Match ID: QYnmAaAAMAAA

• Matt Cohn-Geier moves 3/off 2/1*

#		Ply	Move	Equity
	1	R	3/2 3/off	+1.7827
			0.9450 0.7058 0.0411 - 0.0550 0.0000 0.0000 +1.7934 +1.7827 0.0012 0.0004 0.0003 - 0.0012 0.0000 0.0000 0.0021 0.0025
			Full cubeful rollout with var.redn.
			3822 games, Mersenne Twister dice gen. with seed 806047914 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
•	??	R	3/off 2/1*	+1.7673 ( -0.0154)
			0.9340 0.7239 0.0320 - 0.0660 0.0000 0.0000 +1.7805 +1.7673 0.0011 0.0004 0.0003 - 0.0011 0.0000 0.0000 0.0020 0.0024
			Full cubeful rollout with var.redn.
			3822 games, Mersenne Twister dice gen. with seed 806047914 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Messages In This Thread

• LV Finals Play #1
  Matt Cohn-Geier -- Tuesday, 2 December 2008, at 12:33 a.m.
  • LV Finals Play #1
    tem_sat -- Tuesday, 2 December 2008, at 8:13 a.m.
    • LV Finals Play #1
      Sam Pottle -- Tuesday, 2 December 2008, at 10:15 p.m.
  • LV Finals Play #1
    Havard Raddum -- Tuesday, 2 December 2008, at 12:49 p.m.
  • LV Finals Play #1
    Coolrey -- Tuesday, 2 December 2008, at 1:21 p.m.
  • LV Finals Play #1
    neilkaz -- Tuesday, 2 December 2008, at 5:04 p.m.
  • LV Finals Play #1
    Keene -- Tuesday, 2 December 2008, at 7:49 p.m.
  • LV Finals Play #1 ROLLOUT
    Matt Cohn-Geier -- Thursday, 4 December 2008, at 4:00 a.m.
    • LV Finals Play #1 ROLLOUT
      Sam Pottle -- Thursday, 4 December 2008, at 8:21 a.m.