BBO Discussion Forums: UI problem - BBO Discussion Forums

Jump to content

  • 2 Pages +
  • 1
  • 2
  • You cannot start a new topic
  • You cannot reply to this topic

UI problem

#1 User is offline   gnasher 

  • Andy Bowles
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,993
  • Joined: 2007-May-03
  • Gender:Male
  • Location:London, UK

Posted 2012-April-12, 02:51


Your raise to 3NT was intended as natural, but was alerted and explained (correctly) as non-forcing with four spades.
LHO's double was described as "not discussed but penalty I think".
If partner had redoubled, that would have expressed confidence.

(1) Is the description of this double AI or UI?

(2) Should you ask what a double would have meant in the auction 2NT-3NT(natural)? What if they refuse to answer?

(3) Suppose that you ask, and they say that the double in the authorised auction is also "not discussed but penalty I think". What are the logical alternatives, what's suggested by the UI, and what do you do?

This post has been edited by gnasher: 2012-April-12, 03:06

... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
0

#2 User is offline   WellSpyder 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,627
  • Joined: 2009-November-30
  • Location:Oxfordshire, England

Posted 2012-April-12, 03:04

I assume your first sentence describes the raise to 3N not 2N?

Should I also assume that when bidding 3N I had forgotten the system rather than deliberately psyched?
0

#3 User is offline   gnasher 

  • Andy Bowles
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,993
  • Joined: 2007-May-03
  • Gender:Male
  • Location:London, UK

Posted 2012-April-12, 03:05

View PostWellSpyder, on 2012-April-12, 03:04, said:

I assume your first sentence describes the raise to 3N not 2N?

Should I also assume that when bidding 3N I had forgotten the system rather than deliberately psyched?


Yes and yes - sorry. I've edited the original post.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
0

#4 User is offline   RMB1 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,841
  • Joined: 2007-January-18
  • Gender:Male
  • Location:Exeter, UK
  • Interests:EBU/EBL TD
    Bridge, Cinema, Theatre, Food,
    [Walking - not so much]

Posted 2012-April-12, 03:34

(1) The explanation of double is authorised as an explanation of double in the auction where 3NT is artificial.

(2) I don't think there is a requirement to ask. If you want to know (in order to better determine your logical alternatives) I think you should call the TD, explain the problem away from the table, and follow his direction. (This should deal with "what if they refuse to answer").

(3) I suspect Pass and 5 are LA, and perhaps 4: I would need to poll. I am not at all sure if any LA is suggested over others.
Robin

"Robin Barker is a mathematician. ... All highly skilled in their respective fields and clearly accomplished bridge players."
0

#5 User is offline   WellSpyder 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,627
  • Joined: 2009-November-30
  • Location:Oxfordshire, England

Posted 2012-April-12, 03:36

1) Surely has to be AI - it is an explanation of what the opponents have actually shown, after all, even if it is not the auction you thought it was.

2) It seems sensible to me to ask, yes. The uncertainty over the first explanation means you are not causing any UI problems for your own side since this is an obvious follow-up to ask anyway. If they refuse to answer I guess you just accept that.

3) Pass is certainly a LA. I think it is possible that 4 is too, especially if you are of a nervous disposition, but a poll might be needed to establish that. 5 might be possible too, and indeed redouble - although partner has not expressed confidence, you do have a huge source of tricks. I suppose the UI might suggest pass over 4 since there is presumably some risk if you bid on that partner might decide to put you in a presumed 4-3 fit which would actually only be a 3-3 fit, but I think you could bid 5 over this, anyway. I expect I would pass without UI considerations, and I'm not sure I am constrained in practice to do anything else in the scenario set out.
0

#6 User is offline   paulg 

  • PipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 5,054
  • Joined: 2003-April-26
  • Gender:Male
  • Location:Scottish Borders

Posted 2012-April-12, 04:04

I guess this is not an auction that comes up regularly enough to establish what the 3NT is likely to do. Are his only practical options pass and redouble, or is he allowed to run to four clubs with a 2236 hand or 1345 distribution with singleton K?

If his only options are pass or redouble, then I don't think LAs matter as none will be suggested. If he can pull, then you know (at least a certain percentage of the time) that he will not have pulled 3NT because you have shown four spades. But even then this seems fairly tenuous and, in this situation, the double has not been explained as 'lead spades' or 'lead your shorter major', so I've come to the conclusion that you can do whatever you think is right. There is UI, but no LAs are suggested.
The Beer Card

I don't work for BBO and any advice is based on my BBO experience over the decades
0

#7 User is offline   gnasher 

  • Andy Bowles
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,993
  • Joined: 2007-May-03
  • Gender:Male
  • Location:London, UK

Posted 2012-April-12, 04:26

View PostRMB1, on 2012-April-12, 03:34, said:

(1) The explanation of double is authorised as an explanation of double in the auction where 3NT is artificial.

But isn't it "affected by UI from another source"?

Maybe that's the wrong question, though. What I meant was, can you use that explanation in determining the LAs? If, for example, they tell you that

2NT-pass-3NT(nat)-dbl

asks for a heart lead, I think you can use only that explanation in determining the LAs. Is that correct?

This post has been edited by gnasher: 2012-April-12, 04:31

... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
0

#8 User is offline   lamford 

  • PipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 6,420
  • Joined: 2007-October-15

Posted 2012-April-12, 06:11

View PostWellSpyder, on 2012-April-12, 03:36, said:

I suppose the UI might suggest pass over 4 since there is presumably some risk if you bid on that partner might decide to put you in a presumed 4-3 fit which would actually only be a 3-3 fit, but I think you could bid 5 over this, anyway.

I think bidding 4 is carefully avoiding taking advantage of the UI. Partner may indeed bid 4 on a three-card suit, and you will pretend that is a 4-card suit and pass. However I do not think 4 is an LA, and I think the only LAs are Pass and 5. Neither is particular suggested, whatever the meaning of Double in either auction. You pays your money ...
I prefer to give the lawmakers credit for stating things for a reason - barmar
0

#9 User is offline   nige1 

  • 5-level belongs to me
  • PipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 9,128
  • Joined: 2004-August-30
  • Gender:Male
  • Location:Glasgow Scotland
  • Interests:Poems Computers

Posted 2012-April-12, 06:48

gnasher writes "Your raise to 3NT was intended as natural, but was alerted and explained (correctly) as non-forcing with four spades. LHO's double was described as "not discussed but penalty I think". If partner had redoubled, that would have expressed confidence.
(1) Is the description of this double AI or UI?
(2) Should you ask what a double would have meant in the auction 2NT-3NT(natural)? What if they refuse to answer?
(3) Suppose that you ask, and they say that the double in the authorised auction is also "not discussed but penalty I think". What are the logical alternatives, what's suggested by the UI, and what do you do?

IMO: (1) AI
(2) You may ask but don't have to ask.
(3) Logical alternatives include Pass, XX, 4, 5. Partner;s explanation is UI. It makes it more likely that your partnership lacks a stop. This suggests bidding over passing. Hence, you should pass.

0

#10 User is offline   WellSpyder 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,627
  • Joined: 2009-November-30
  • Location:Oxfordshire, England

Posted 2012-April-12, 06:51

View Postlamford, on 2012-April-12, 06:11, said:

Partner may indeed bid 4 on a three-card suit, and you will pretend that is a 4-card suit and pass.

Good point, which I missed earlier. You are, of course, still constrained by UI on the next round and I agree that if you bid 4 and partner responds 4 then pass is indeed a LA (and 5 would be suggested over this by the UI).
0

#11 User is offline   RMB1 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,841
  • Joined: 2007-January-18
  • Gender:Male
  • Location:Exeter, UK
  • Interests:EBU/EBL TD
    Bridge, Cinema, Theatre, Food,
    [Walking - not so much]

Posted 2012-April-12, 07:07

View Postgnasher, on 2012-April-12, 04:26, said:

Maybe that's the wrong question, though. What I meant was, can you use that explanation in determining the LAs? If, for example, they tell you that
2NT-pass-3NT(nat)-dbl
asks for a heart lead, I think you can use only that explanation in determining the LAs. Is that correct?

Yes. I think that if you have an explanation of 2N-P-3NT(nat)-X then only that explanation should be used when determining LAs.

But if all you have is the explanation given, then you should determine LAs on the basis that the auction was 2NT-P-3NT(nat)-X where X is explained as "no explanation on this sequence, but if 3NT showed 4 then double is ....".
Robin

"Robin Barker is a mathematician. ... All highly skilled in their respective fields and clearly accomplished bridge players."
0

#12 User is offline   WellSpyder 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,627
  • Joined: 2009-November-30
  • Location:Oxfordshire, England

Posted 2012-April-12, 07:31

View PostRMB1, on 2012-April-12, 07:07, said:

Yes. I think that if you have an explanation of 2N-P-3NT(nat)-X then only that explanation should be used when determining LAs.

But if all you have is the explanation given, then you should determine LAs on the basis that the auction was 2NT-P-3NT(nat)-X where X is explained as "no explanation on this sequence, but if 3NT showed 4 then double is ....".

I understand the logic behind this, I think, but it sounds quite tricky in practice. Does it mean that you really ought to ask about the first sequence even if the explanation of the second sequence is quite clear (eg "it asks for a spade lead")? Your first response indicated that you didn't think there was an obligation to ask, but you might well expect the answer to be different (eg "it asks for a heart lead"). Perhaps the decision not to ask is an example of choosing between LAs (both asking and not asking are presumably LAs?) because of the UI you have????? It seems quite easy to tie yourself in knots, here.
0

#13 User is offline   RMB1 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,841
  • Joined: 2007-January-18
  • Gender:Male
  • Location:Exeter, UK
  • Interests:EBU/EBL TD
    Bridge, Cinema, Theatre, Food,
    [Walking - not so much]

Posted 2012-April-12, 08:02

View PostWellSpyder, on 2012-April-12, 07:31, said:

... It seems quite easy to tie yourself in knots, here.


Definitely. I would be entirely satisfied with a player who called me at the end of the hand and explained that he knew he had UI and had tried to avoid using it (Law 73) - but could not get his mind round what were logical alternatives and what was suggested (Law 16).
Robin

"Robin Barker is a mathematician. ... All highly skilled in their respective fields and clearly accomplished bridge players."
0

#14 User is offline   WellSpyder 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,627
  • Joined: 2009-November-30
  • Location:Oxfordshire, England

Posted 2012-April-12, 08:17

View PostRMB1, on 2012-April-12, 08:02, said:

I would be entirely satisfied with a player who called me at the end of the hand and explained that he knew he had UI and had tried to avoid using it (Law 73) - but could not get his mind round what were logical alternatives and what was suggested (Law 16).

That's good to know. But I must admit I'm still not entirely convinced that I shouldn't be taking account of what my opponents bids mean in the auction we are actually having, rather than the one I have to pretend we are having. Is the following thought experiment any use?

I tend to think of the implications of disclosure as being a situation where the opponents are always entitled to know what your bids mean, and you are always entitled to know what their bids mean, but you are not necessarily entitled to know what your bids mean (and, of course, you are not entitled to know what your partner thinks they mean). One way of achieving this without screens is to imagine playing on computers but where you still explain your partner's bids not your own. So in the case under discussion, the explanation of 3N would pop up on your opponents' screens, but you would have no way of knowing this. Then the explanation of their bid (x asks for a spade lead, say) would pop up on your screen, but you have no way of knowing why it asks for that (in this case maybe because you actually showed spades), simply that that is what is shows. That seems OK to me, and it seems equivalent in the actual case to say you can use info about what the opponent has actually shown, rather than what he would have been showing with a different explanation of your bid, regardless of which explanation of your bid is actually right.
0

#15 User is offline   Phil 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,092
  • Joined: 2008-December-11
  • Gender:Male
  • Location:North Texas, USA
  • Interests:Mountain Biking

Posted 2012-April-12, 12:03

This is the part of the question I am struggling with:

Quote

(1) Is the description of this double AI or UI?


I cannot see how it can be AI. Partner's explanation wakes us from our slumber, so how can we have the right to differentiate between a standard 2N - p - 3N - x and a conventional* 2N - p - 3N* - x?

The wall analogy arises here. I cannot hear my partner's alert, so the only explanation of the double that is authorized information to me is how they play the double in a standard 2N - p - 3N - x auction. But yet...

Muddling through:

Quote

(2) Should you ask what a double would have meant in the auction 2NT-3NT(natural)? What if they refuse to answer?


You can ask, and they would required to disclose their agreements. I am very uncomfortable when the partner who has misbid starts the interrogation, because it potentially transmits to his partner, "I forgot". Here, that is specifically what will happen, since it is such a leading question: "What does the double over a NATURAL 3N be"? Uh huh, sure.

I would feel a lot better if the 2N opener were to be asking the questions.

Quote

(3) Suppose that you ask, and they say that the double in the authorised auction is also "not discussed but penalty I think". What are the logical alternatives, what's suggested by the UI, and what do you do?


Assuming the wall is still up, its a judgment call, but why would you pull? I can see taking a flyer in 3N over a 1N opener with this same hand type, and pulling to 4 if it gets smacked. However, pulling over 2N it seems wrong to me. We have a great source of tricks and they haven't taken five tricks yet. However, the only way to know for sure is to poll your peers with the exact hand and ask them leaving out the alert.

As far as partner's alert about NF with four spades, I don't think this explanation and partner's subsequent pass suggests anything about bidding or sitting.
Hi y'all!

Winner - BBO Challenge bracket #6 - February, 2017.
0

#16 User is offline   FrancesHinden 

  • Limit bidder
  • PipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 8,482
  • Joined: 2004-November-02
  • Gender:Female
  • Location:England
  • Interests:Bridge, classical music, skiing... but I spend more time earning a living than doing any of those

Posted 2012-April-12, 12:10

View PostWellSpyder, on 2012-April-12, 03:36, said:

I suppose the UI might suggest pass over 4 since there is presumably some risk if you bid on that partner might decide to put you in a presumed 4-3 fit which would actually only be a 3-3 fit....


But as other people have said, the UI suggests pulling over passing because we have fewer spades than we might have done and partner might be thinking his spade stop is more robust than it actually is.
I don't think any particular LA is demonstrably suggested, and I can't see what you could do that would be taking advantage of the UI, so I think you can do what you fancy.

p.s. given I know the hand, why did partner forget to redouble?
0

#17 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,919
  • Joined: 2009-July-13
  • Location:England

Posted 2012-April-12, 12:19

View PostWellSpyder, on 2012-April-12, 03:36, said:

3) Pass is certainly a LA. I think it is possible that 4 is too, especially if you are of a nervous disposition, but a poll might be needed to establish that. 5 might be possible too, and indeed redouble - although partner has not expressed confidence, you do have a huge source of tricks. I suppose the UI might suggest pass over 4 since there is presumably some risk if you bid on that partner might decide to put you in a presumed 4-3 fit which would actually only be a 3-3 fit, but I think you could bid 5 over this, anyway. I expect I would pass without UI considerations, and I'm not sure I am constrained in practice to do anything else in the scenario set out.

If you decide that pass is not an LA (and I would here, double of a freely bid 3N by the hand not on lead is usually a running or near running suit specific or otherwise and you can see 3 of them to choose from), are you allowed to foresee the UI problem that you're going to have if partner hypothetically bids 4 over your 4 and bid 5 instead precisely to avoid that problem ?
0

#18 User is offline   sfi 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,576
  • Joined: 2009-May-18
  • Location:Oz

Posted 2012-April-12, 13:32

View PostCyberyeti, on 2012-April-12, 12:19, said:

If you decide that pass is not an LA (and I would here, double of a freely bid 3N by the hand not on lead is usually a running or near running suit specific or otherwise and you can see 3 of them to choose from), are you allowed to foresee the UI problem that you're going to have if partner hypothetically bids 4 over your 4 and bid 5 instead precisely to avoid that problem ?


No - that would be choosing an option suggested by the UI, because it's easy to foresee winding up in a 3-3 spade fit. On the actual hand I can't see wanting to play a part score in diamonds rather than a game though, so don't think 4D is a logical alternative anyway. Agree with the posters who say that the UI doesn't particularly suggest pass or 5D over the other.

Any agreements on redouble from this hand in the pass-out seat?
0

#19 User is offline   gnasher 

  • Andy Bowles
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,993
  • Joined: 2007-May-03
  • Gender:Male
  • Location:London, UK

Posted 2012-April-12, 16:16

View Postsfi, on 2012-April-12, 13:32, said:

Any agreements on redouble from this hand in the pass-out seat?

That would express confidence too.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
0

#20 User is offline   gnasher 

  • Andy Bowles
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,993
  • Joined: 2007-May-03
  • Gender:Male
  • Location:London, UK

Posted 2012-April-12, 16:19

View PostFrancesHinden, on 2012-April-12, 12:10, said:

p.s. given I know the hand, why did partner forget to redouble?

I didn't ask. When you've just scored +950 by forgetting your system, a question like "Why didn't you redouble?" might be construed a breach of Law 74A2.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
0

  • 2 Pages +
  • 1
  • 2
  • You cannot start a new topic
  • You cannot reply to this topic

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users