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Game 3, move 16: Herd 6-2

Poll

Move

7/5
6 (54.5%)
4/2
3 (27.3%)
6/4
2 (18.2%)

Total Members Voted: 11

Voting closed: May 21, 2012, 01:24:48 PM

Author Topic: Game 3, move 16: Herd 6-2  (Read 1664 times)

Offline diane

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Game 3, move 16: Herd 6-2
« on: May 20, 2012, 01:20:46 PM »
Steifnu danced again with 2-4

The 6 isnt playing anywhere..so just the 2 to decide on.
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Game 3, move 16: Herd 6-2
« on: May 20, 2012, 01:20:46 PM »

Offline ah_clem

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Re: Game 3, move 16: Herd 6-2
« Reply #1 on: May 20, 2012, 01:30:05 PM »
[spoiler]
7/5 gives us a nice distribution at the expense of only 2 shots (after which he'll still have two checkers stuck behind a 5 prime).  But I'm not convinced it's worth it, so I'll go for one of the safe plays.

4/2 keeps us even-ended, but 6/4 seems to be more flexible.  I'll go for that. 

6/4.
[/spoiler]

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Re: Game 3, move 16: Herd 6-2
« Reply #1 on: May 20, 2012, 01:30:05 PM »

Offline Julia_H

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Re: Game 3, move 16: Herd 6-2
« Reply #2 on: May 20, 2012, 01:54:01 PM »
[spoiler]I think 4/2, the leading choice right now, is the worst of the 3 - piling up on the highest and lowest points in the board with no spares in between is a recipe for plenty of awkward rolls in the bearoff, while White has time to stick around. I think 6/4 is the best, but I'm not sure... there are a lot of sequences which are bad for us where a 5 leaves a blot inside the board. At least after 7/5 and a hit we still have two men trapped.[/spoiler]

Offline NIHILIST

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Re: Game 3, move 16: Herd 6-2
« Reply #3 on: May 20, 2012, 06:57:10 PM »
i opt for 7-5. Take a small risk now to avoid a big problem later. It smoothes out our distribution which is good for our bearoff. It avoids jagoff scenarios like him entering with 1-X followed by our 6-5 ( if we make one of the other plays ).

I amost have to wonder, if you're afraid to take a 2 number risk when hes on the bar, what will you do when the genuine tough choices present themselves.

Bob
Robert J Ebbeler

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Re: Game 3, move 16: Herd 6-2
« Reply #3 on: May 20, 2012, 06:57:10 PM »

Offline diane

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Re: Game 3, move 16: Herd 6-2
« Reply #4 on: May 20, 2012, 09:37:08 PM »
I amost have to wonder, if you're afraid to take a 2 number risk when hes on the bar, what will you do when the genuine tough choices present themselves.

This is why I put this choice in..I wonder about this risk...it does leave room for the 1-6 to completely break our fairly sure game here. It might make the next roll easier if he doesnt roll 6-1, but is that risk really worth it?

With his 4 point board, if he does roll 6-1, we may well end up snatching defeat from the jaws of victory.
Never give up on the things that make you smile

Offline manxcat

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Re: Game 3, move 16: Herd 6-2
« Reply #5 on: May 20, 2012, 09:56:32 PM »
75 for the same reasoning as Bob's
I would rather be villified for doing the right thing, than be praised for doing the wrong thing. -unknown, very likely it was me.

Offline praine

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Re: Game 3, move 16: Herd 6-2
« Reply #6 on: May 20, 2012, 09:56:56 PM »
[spoiler]I think arguments for both plays are sound, and they are probably quite close, but I'd like to take the two shot risk for superior distribution against his ace-point game.
[/spoiler]

Offline ah_clem

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Re: Game 3, move 16: Herd 6-2
« Reply #7 on: May 21, 2012, 02:31:30 PM »
rollout


[spoiler]
A fairly close one: the better distribution after 7/5 is not worth leaving two shots, but 7/5 is better than prematurely burying a checker on the deuce.



XGID=abBBCBDB---------b-dbb-b--:1:1:1:62:4:1:0:5:10


    1. Rollout¹    6/4                          eq:+0.632
      Player:   81.71% (G:45.48% B:15.71%)
      Opponent: 18.29% (G:0.12% B:0.00%)
      Confidence: ±0.004 (+0.628..+0.635) - [100.0%]
      Duration: 4 minutes 43 seconds

    2. Rollout¹    7/5                          eq:+0.608 (-0.024)
      Player:   80.56% (G:46.71% B:16.78%)
      Opponent: 19.44% (G:0.16% B:0.01%)
      Confidence: ±0.004 (+0.604..+0.612) - [0.0%]
      Duration: 3 minutes 49 seconds

    3. Rollout¹    4/2                          eq:+0.581 (-0.050)
      Player:   79.21% (G:43.14% B:13.98%)
      Opponent: 20.79% (G:0.13% B:0.01%)
      Confidence: ±0.004 (+0.578..+0.585) - [0.0%]
      Duration: 3 minutes 45 seconds

    4. 2-ply       5/3                          eq:+0.356 (-0.276)
      Player:   69.96% (G:25.11% B:1.99%)
      Opponent: 30.04% (G:2.08% B:0.08%)


¹  1296 Games rolled with Variance Reduction.
   Moves: 3-ply, cube decisions: XG Roller


eXtreme Gammon Version: 2.03, MET: Kazaross XG2


[/spoiler]

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Re: Game 3, move 16: Herd 6-2
« Reply #7 on: May 21, 2012, 02:31:30 PM »

Offline ah_clem

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Re: Game 3, move 16: Herd 6-2
« Reply #8 on: May 21, 2012, 05:39:33 PM »
more rollout

[spoiler]

Match score makes a difference here.  At 0-0 to 5 and the cube centered, 7/5 is correct.

The reason is that 7/5 wins more gammons. 6/4 still wins more single games.


XGID=abBBCBDB---------b-dbb-b--:0:0:1:62:0:0:0:5:10

X:Player 1   O:Player 2
Score is X:0 O:0 5 pt.(s) match.
 +13-14-15-16-17-18------19-20-21-22-23-24-+
 |             O    |   | O  O  O     O    |
 |             O    |   | O  O  O     O    |
 |                  |   | O                |
 |                  |   | O                |
 |                  |   |                  |
 |                  |BAR|                  |
 |                  | O |                  |
 |                  |   | X                |
 |                  |   | X     X          |
 |                X |   | X  X  X  X  X  O |
 |                X |   | X  X  X  X  X  O |
 +12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 70  O: 135 X-O: 0-0/5
Cube: 1
X to play 62

    1. Rollout¹    7/5                          eq:+1.074
      Player:   82.37% (G:40.47% B:3.83%)
      Opponent: 17.63% (G:0.15% B:0.00%)
      Confidence: ±0.008 (+1.066..+1.081) - [99.6%]
      Duration: 10 minutes 16 seconds

    2. Rollout¹    6/4                          eq:+1.058 (-0.015)
      Player:   83.09% (G:38.37% B:3.51%)
      Opponent: 16.91% (G:0.09% B:0.00%)
      Confidence: ±0.008 (+1.050..+1.067) - [0.4%]
      Duration: 9 minutes 49 seconds



¹  1296 Games rolled with Variance Reduction.
   Moves: 3-ply, cube decisions: XG Roller


eXtreme Gammon Version: 2.03, MET: Kazaross XG2

[/spoiler]

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