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Another percentage problem

#1 User is offline   Fluffy 

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Posted 2016-September-07, 02:19



You can dismiss the chances of partner having 0 keycards because he would had bid 4NT over 4.

Basically partner has Axxx Axxx Axx xx almost for sure (with 3 clubs he would not bid 3NT over 3 having 3 aces). And there is a slight chance partner has another jack.

What is the best contract IMP-wise?
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#2 User is offline   Kaitlyn S 

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Posted 2016-September-07, 07:28

With the two hands you've given, 6D is best. However, why can't partner hold either of these?

S-Axxx H-Axxx D-AJx C-Jx

or

S-Axx H-Axxx D-Axxx C-xx

In the second one I clearly want to be in 7D. In the first one, 7NT gets the top score in Challenge the Champs but 7D is respectable.
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#3 User is offline   Fluffy 

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Posted 2016-September-07, 15:14

View PostKaitlyn S, on 2016-September-07, 07:28, said:

With the two hands you've given, 6D is best. However, why can't partner hold either of these?

S-Axxx H-Axxx D-AJx C-Jx

or

S-Axx H-Axxx D-Axxx C-xx

In the second one I clearly want to be in 7D. In the first one, 7NT gets the top score in Challenge the Champs but 7D is respectable.


A: Because he has denied more than 13 HCP. His exact range is 11-13.

B: Because he has denied 4 diamonds.
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#4 User is offline   Cyberyeti 

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Posted 2016-September-07, 15:21

I suspect 6, the hand you want to be in 7 is AJx (even more so if the x is 10 or 9), 10x in the minors, but that's unlikely.
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#5 User is offline   Tramticket 

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Posted 2016-September-07, 15:42

The title suggests it is a percentage problem. 7D needs the diamonds to be 3-2 and clubs to behave ... E.g. clubs 3-3 or 4-2 with the hand holding the doubleton also holding a doubleton diamond. This looks like pretty poor odds for a grand slam - even without calculating the odds properly.

Unless the state of the match suggests otherwise(?) the small slam is high enough?
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#6 User is offline   Fluffy 

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Posted 2016-September-09, 11:02

Thanks for those who answered, I was mildly critizied when I opted for small slam. Turns out partner has J10 so grand is good, and diamonds behave.

Partner said maybe I could try 5NT since he can't have anything but another jack, so he cannot go wrong... not sure if he is just resulting.
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#7 User is offline   WesleyC 

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Posted 2016-September-12, 12:00

IMO this is another decision which feels important at the time but in the long term is hardly going to matter either way.

Even if partner holds perfect cards, your best case scenario is getting to a marginally positive grand. I'd worry about another hand heh
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#8 User is offline   nige1 

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Posted 2016-September-12, 17:44

View PostFluffy, on 2016-September-09, 11:02, said:

Thanks for those who answered, I was mildly critizied when I opted for small slam. Turns out partner has J10 so grand is good, and diamonds behave. Partner said maybe I could try 5NT since he can't have anything but another jack, so he cannot go wrong... not sure if he is just resulting.
Excellent seminars by top experts at the Eastbourne Congress are avidly attended by would-be improvers. Simon Cope treated us to a lecture on slam-bidding. One of his many recommendations, new to me, is:

After you establish that your side holds all the key-cards, if a good grand is possible, then you must bid 5N (or whatever) to tell partner. You provide him with the opportunity to boot the grand when he thinks that he holds a useful surprise.
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#9 User is offline   gszes 

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Posted 2016-September-13, 09:20

View PostFluffy, on 2016-September-09, 11:02, said:

Thanks for those who answered, I was mildly critizied when I opted for small slam. Turns out partner has J10 so grand is good, and diamonds behave.

Partner said maybe I could try 5NT since he can't have anything but another jack, so he cannot go wrong... not sure if he is just resulting.

It seems perfectly safe to ask where an extra J might be located. The appearance of the club J (as well as the virtual certainty it is Jx) in p hand seems to make a grand slam a worthwhile venture.
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#10 User is offline   cherdano 

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Posted 2016-September-13, 23:00

View PostWesleyC, on 2016-September-12, 12:00, said:

IMO this is another decision which feels important at the time but in the long term is hardly going to matter either way.

Even if partner holds perfect cards, your best case scenario is getting to a marginally positive grand. I'd worry about another hand heh

I really disagree with this attitude. Every small edge counts! If you keep leaking an expected value -0.5 IMP here and there, then suddenly you have lowered your odds of winning a 96 board match significantly. You don't want to miss a 65% grand where the other table is certainly in slam. Good players don't win game swings because they find one ingenious thing to do, they win game swings because they consistently find slightly better plays that pay off now and then.

I really think 5N is right here - there is no hand where partner will bid grand and it is wrong. He knows that I know that he can only have another jack. The odds of him having a minor jack are non-trivial, and when he does, he may figure out to bid 6 or 7.
The easiest way to count losers is to line up the people who talk about loser count, and count them. -Kieran Dyke
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#11 User is offline   WesleyC 

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Posted 2016-September-14, 07:37

View Postcherdano, on 2016-September-13, 23:00, said:

I really disagree with this attitude. Every small edge counts! If you keep leaking an expected value -0.5 IMP here and there, then suddenly you have lowered your odds of winning a 96 board match significantly. You don't want to miss a 65% grand where the other table is certainly in slam. Good players don't win game swings because they find one ingenious thing to do, they win game swings because they consistently find slightly better plays that pay off now and then.

I really think 5N is right here - there is no hand where partner will bid grand and it is wrong. He knows that I know that he can only have another jack. The odds of him having a minor jack are non-trivial, and when he does, he may figure out to bid 6 or 7.


I agree with you in principle - small edges certainly matter - but experience has taught me that seeking out small edges in grand-slam boards never works as well in practice as it does in theory.

The opponents are very likely to be in slam but (as always) the chance isn't 100%. Maybe teammates get 'caught' in an aggressive preempt and manage to get out for -1100. Maybe the opponents have a misunderstanding and land in an inferior slam? Maybe partner is reading the same "small edges" playbook and decides to bid 6NT over 5NT holding [AT9x AJTx Axx xx] because it might be safer and/or worth an extra couple of IMPs. Maybe partner pictures us with a hand like [x x KQJTx AKxxxx] and accepts on the basis that it's a club doubleton that we are looking for?

In other news after Fluffy comfortably took care of my NZ buddies i'm forced to start cheering for him against Monaco! Good Luck!
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