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12-03-2016 , 05:04 AM

midiboy

centurion

Join Date: Jun 2013 Posts: 104

What's your play? Why?

White - Pips 130. Match Score 0/3 (C)

Black - Pips 126. Match Score 2/3 (C)
Black to Play 6-3
Created with www.BGdiagram.com

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12-03-2016 , 10:07 AM

Robertie

old hand

Join Date: May 2004 Posts: 1,954

I'd like to get my back checker out but 24/15 leaves 16 shots, which looks like way too much just to get into a race. So I'll opt for one of the hits.

13/7* 10/7 leaves 7 shots (51, 41, 21, and 11) while 13/7* 13/10 leaves only 6 (61, 52, and 43). But the hits after 13/7* 13/10 are much worse since White is hitting and escaping at the same time. So I'll vote for 13/7* 10/7.

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12-04-2016 , 11:20 AM

midiboy

centurion

Join Date: Jun 2013 Posts: 104

I had the same considerations, and played 13/7* 10/7. I was surprised to have gotten dinged for the move, and more surprised to see how much better 24/15 is.

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12-05-2016 , 10:21 AM

Robertie

old hand

Join Date: May 2004 Posts: 1,954

Very interesting, and I don't have a clear explanation for it. Looks like the combination of the lost midpoint, the awkward stack on the 6-point, and White's 4-prime combine to make trying to break contact the best option. I would never have found this over the board, however.

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12-05-2016 , 10:57 AM

Alpha Fish

Pooh-Bah

Join Date: Aug 2008 Posts: 3,826

I'm sure Bill is simply overlooking the fact that it's a Crawford game. Just look at win % and gammon shares and it's clear that 13/7* 10/7 would be a top choice for money game

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12-06-2016 , 10:19 AM

Robertie

old hand

Join Date: May 2004 Posts: 1,954

I did a rollout for a cash game and 24/15 was still clearly right. Very interesting position.

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12-06-2016 , 12:10 PM

midiboy

centurion

Join Date: Jun 2013 Posts: 104

Same here. 24/15 comes out ahead.

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12-06-2016 , 02:02 PM

I.E.

stranger

Join Date: Nov 2014 Posts: 12

I think duplication of 3s, which nobody mentioned, is a huge factor here.

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12-06-2016 , 07:32 PM

RolldUpTrips

old hand

Join Date: Oct 2006 Posts: 1,334

Quote:

Originally Posted by I.E.

I think duplication of 3s, which nobody mentioned, is a huge factor here.

It's simply a "factor" that makes the play safer than it would be if the two blots could be hit by different numbers. It's implied as factored into everyone's thinking when we count shots (16 in this case)

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12-07-2016 , 06:16 AM

#10

Alpha Fish

Pooh-Bah

Join Date: Aug 2008 Posts: 3,826

Quote:

Originally Posted by Robertie

I did a rollout for a cash game and 24/15 was still clearly right. Very interesting position.

Strange. I guess there was some sort of glitch displaying gammon and bg win %'s in OP, since simply adding all of them up had the hit clearly ahead. I did the rollout myself and got totally different wg & wbg %'s.

fun fact: if you move 2 black checkers from 3 to 4 13/7* 10/7 is way ahead again

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12-07-2016 , 04:24 PM

#11

midiboy

centurion

Join Date: Jun 2013 Posts: 104

I rolled it out again using GNU and got pretty close to the same numbers.

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