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Count vs. Restricted Choice

#1 User is offline   EricK 

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Posted 2014-April-15, 13:38

You get to 7NT after the sequence 1NT 7NT. Your are AJx opposite KTx. You get a complete count of the hand and you know LHO started with 3 (and hasn't discarded any), and RHO has 3 left as well. All else being equal, you should play RHO for the Q and the probability the finesse would win is 4/7.

But suppose your count of the hand shows that LHO started with, say, ?xx xxx Jxx Txxx. Should you apply restricted choice to LHO's opening lead choice and say if RHO had the Q, then LHO might equally have chosen to lead a from xxx, whereas with Qxx he wouldn't lead a , so the probability that LHO has xxx is not 4/7, but only 2/7. In which case we should play LHO for the Queen.
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#2 User is offline   Fluffy 

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Posted 2014-April-15, 13:41

yes, restricted choice applies, but only if he led a heart, and not from a safelooking suit like 98x.
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#3 User is offline   EricK 

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Posted 2014-April-15, 14:24

 Fluffy, on 2014-April-15, 13:41, said:

yes, restricted choice applies, but only if he led a heart, and not from a safelooking suit like 98x.

Yes. I meant to say the lead was a Heart!
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#4 User is offline   EricK 

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Posted 2014-April-15, 15:31

Follow up question: So if instead of trebletons, LHO majors were both doubletons i.e the have split 5-2, and the lead was, say, from 73, then we shouldn't play the person with 5 for the Queen ("naive" probability 5/7), but should play the opening leader for a doubleton Queen (probability 1 - 1/2 x 5/7 = 9/14)? Because that almost renders the process of counting a hand like that pointless!
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#5 User is offline   larlar 

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Posted 2014-April-15, 16:11

If the suit is 5-2 then it is 2.5 times more likely that the hand with 5 has the queen. Even with restricted choice (2-1) with xx in each major, it is more likely the hand with 5 spades has the queen
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#6 User is offline   winkle 

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Posted 2014-April-15, 16:20

Sometimes when I count out a hand I find that LHO has 2 cards in a suit to RHO's 3 and I finesse... into LHO's doubleton Q. @(#*@(*#(*#@.

Sometimes when I count out a hand I find that I've gained 2% from not counting at all. @*#@#*(@#*@#*.

A few more and I swear I'm going to switch to chess, or go, or tic-tac-toe.
My name is Winkle.
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#7 User is offline   gszes 

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Posted 2014-April-15, 20:04

 winkle, on 2014-April-15, 16:20, said:

Sometimes when I count out a hand I find that LHO has 2 cards in a suit to RHO's 3 and I finesse... into LHO's doubleton Q. @(#*@(*#(*#@.

Sometimes when I count out a hand I find that I've gained 2% from not counting at all. @*#@#*(@#*@#*.

A few more and I swear I'm going to switch to chess, or go, or tic-tac-toe.


Don't give up yet we always seem to recall the irritants and forget the successes. a 60% shot still
goes down 2 out of 5 times so keep track of all of your count related decisions and see how it works
out in the long run:))))))))))))))))))))))
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#8 User is offline   1eyedjack 

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Posted 2014-April-15, 22:17

 EricK, on 2014-April-15, 13:38, said:

You get to 7NT after the sequence 1NT 7NT. Your are AJx opposite KTx. You get a complete count of the hand and you know LHO started with 3 (and hasn't discarded any), and RHO has 3 left as well. All else being equal, you should play RHO for the Q and the probability the finesse would win is 4/7.


I am not convinced by this. IMO it depends on whether your knowledge of the count of the suit derives from its being extracted from the opponents under duress or whether that information had been volunteered by them.

If they volunteered the count when instead one of them might have discarded a spade, then they could be doing so in order to persuade you that the Q is in the 4 card suit when it is not.

This is all pre restricted choice adjustments of course
Psych (pron. saik): A gross and deliberate misstatement of honour strength and/or suit length. Expressly permitted under Law 73E but forbidden contrary to that law by Acol club tourneys.

Psyche (pron. sahy-kee): The human soul, spirit or mind (derived, personification thereof, beloved of Eros, Greek myth).
Masterminding (pron. mPosted ImagesPosted ImagetPosted Imager-mPosted ImagendPosted Imageing) tr. v. - Any bid made by bridge player with which partner disagrees.

"Gentlemen, when the barrage lifts." 9th battalion, King's own Yorkshire light infantry,
2000 years earlier: "morituri te salutant"

"I will be with you, whatever". Blair to Bush, precursor to invasion of Iraq
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#9 User is offline   dake50 

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Posted 2014-April-15, 22:25

I am not convinced by this. IMO it depends on whether your knowledge of the count of the suit derives from its being extracted from the opponents under duress or whether that information had been volunteered by them.
If they volunteered the count when instead one of them might have discarded a spade, then they could be doing so in order to persuade you that the Q is in the 4 card suit when it is not.
This is all pre restricted choice adjustments of course -- 1eyedjack

*** So I should always choose to discard from S:Qxx when declarer is trying to count out H+D+C??
I'll keep that justification in mind.
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#10 User is offline   1eyedjack 

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Posted 2014-April-15, 22:35

 dake50, on 2014-April-15, 22:25, said:

*** So I should always choose to discard from S:Qxx when declarer is trying to count out H+D+C??
I'll keep that justification in mind.


Are you being sarcastic? I find it hard to tell sometimes.

Let me pose another. If a defender had discarded a Spade, would you as declarer be persuaded to play for the drop?

BTW I don't think that you should ALWAYS discard from Qxx. That predictability may well lead to playing for the drop giving a better than 50% edge to declarer. I don't know the math but I suspect that playing at random from a population of all small cards including low Spades would render declarer a 50% guess (before restricted choice on lead). But this would certainly seem to indicate playing x from Qxx SOME of the time.

It is not actually clear to me that the drop is best if BOTH defenders let go a Spade (voluntarily) but am willing to be convinced that that is the case.




Psych (pron. saik): A gross and deliberate misstatement of honour strength and/or suit length. Expressly permitted under Law 73E but forbidden contrary to that law by Acol club tourneys.

Psyche (pron. sahy-kee): The human soul, spirit or mind (derived, personification thereof, beloved of Eros, Greek myth).
Masterminding (pron. mPosted ImagesPosted ImagetPosted Imager-mPosted ImagendPosted Imageing) tr. v. - Any bid made by bridge player with which partner disagrees.

"Gentlemen, when the barrage lifts." 9th battalion, King's own Yorkshire light infantry,
2000 years earlier: "morituri te salutant"

"I will be with you, whatever". Blair to Bush, precursor to invasion of Iraq
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#11 User is offline   Fluffy 

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Posted 2014-April-16, 00:06

When opponent's need to find a queen, you only need 4 defensive cards on the suit (and the queen not to be stiff in the end), you can pitch all the rest, but it gives away some info showing more pips.
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#12 User is offline   nielsfoged 

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Posted 2014-April-16, 09:22

 Fluffy, on 2014-April-16, 00:06, said:

When opponent's need to find a queen, you only need 4 defensive cards on the suit (and the queen not to be stiff in the end), you can pitch all the rest, but it gives away some info showing more pips.

I like discarding once from Qxx - it makes 7NT down 2! :P
/Niels
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#13 User is offline   Lovera 

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Posted 2014-April-27, 06:44

Designate a card, any card that is played before groped the impasse. If the designated card will be played from the East, joined 2% probability of assigning the missing Queen in the West and vice versa. With two cards +4% and so on. (Paul Lucaks).(Lovera)
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