BBO Discussion Forums: negative inferences alertable? - BBO Discussion Forums

Jump to content

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

negative inferences alertable? with an example

#1 User is offline   billw55 

  • enigmatic
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,757
  • Joined: 2009-July-31
  • Gender:Male

Posted 2012-June-15, 08:51

My partner and I play Jacoby 2NT. The other night at the club, we had this uncontested auction:

1 - 2NT! - 4 - all pass.

Seems pretty simple to me. After the auction, RHO (one of the strong players at the club) informed us that 4 must be alerted because it carries additional information: no shortness and minimum values. We had a brief talk about it; I thought that since the bid is natural and a signoff, there is no need to alert it. He maintained that the denial of shortness makes the call alertable.

Note, this was an entirely friendly situation, nobody was seeking a ruling or getting their feathers up, so we did not call the director. On the next hand, after LHO opened and my partner passed, I (being a wiseguy) alerted and explained that pass denies holding 20+ points. RHO rolled his eyes a little, probably justifiably, but my point was that almost every bid denies something.

So which is it? And in general, what types of negative inferences are alertable?
Life is long and beautiful, if bad things happen, good things will follow.
-gwnn
0

#2 User is offline   barmar 

  • PipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Admin
  • Posts: 21,594
  • Joined: 2004-August-21
  • Gender:Male

Posted 2012-June-15, 09:05

Jurisdiction? There are different alert rules for every NBO.

#3 User is offline   billw55 

  • enigmatic
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,757
  • Joined: 2009-July-31
  • Gender:Male

Posted 2012-June-15, 09:12

View Postbarmar, on 2012-June-15, 09:05, said:

Jurisdiction? There are different alert rules for every NBO.

Sorry, ACBL.
Life is long and beautiful, if bad things happen, good things will follow.
-gwnn
0

#4 User is offline   bluejak 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,686
  • Joined: 2007-August-23
  • Gender:Male
  • Location:Liverpool, UK
  • Interests:Bridge Laws, Cats, Railways, Transport timetables

Posted 2012-June-15, 09:40

The jurisdiction is important: for example, in the ACBL, 4 is not alertable at the time though could be alerted at the end of the auction.

The answer to the question is that what negative inferences are alertable depends on what the jurisdiction defines. Now, I do not know where, but on RGB I have been told that the ACBL have actually said that negative inferences are not alertable.

To compare, the EBU says

Quote

5 E Basic alerting rules
5 E 1 Passes and bids
Unless it is announceable (see 5 C and 5 D), a pass or bid must be alerted if
(a) it is not natural; or
(b) it is natural but has a potentially unexpected meaning.

So, if it is below 4 [bids above 3NT are not alertable after the opening bid] then a negative inference makes a bid alertable if that makes it a "potentially unexpected meaning". That would be one that the opponents are really unlikely to expect.

Suppose you play
1 - 2NT [Jacoby] - 3 as any hand with no side suit and at least six spades, and you always bid a side suit if you have one [3, 3, 4]. Is 3 alertable in the EBU?

In my view, yes, because while natural it clearly denies more than five spades, and that is a meaning that would not be expected.

But would it be alertable in the ACBL? Perhaps not!
David Stevenson

Merseyside England UK
EBL TD
Currently at home
Visiting IBLF from time to time
<webjak666@gmail.com>
0

#5 User is offline   jh51 

  • PipPipPipPip
  • Group: Full Members
  • Posts: 231
  • Joined: 2009-November-17

Posted 2012-June-15, 10:06

View Postbluejak, on 2012-June-15, 09:40, said:

Suppose you play
1 - 2NT [Jacoby] - 3 as any hand with no side suit and at least six spades, and you always bid a side suit if you have one [3, 3, 4]. Is 3 alertable in the EBU?


Just as a matter of courisity, if this is your set of rebids after 2NT, is it still appropriate to call 2NT Jacoby? The standard set of rebids is for the 3 level rebids other than the agreed suit to show shortness. At what point of modifying the rebids does 2NT stop being Jacoby and become a game forcing 2NT (not Jacoby)?
0

#6 User is offline   billw55 

  • enigmatic
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,757
  • Joined: 2009-July-31
  • Gender:Male

Posted 2012-June-15, 10:19

View Postjh51, on 2012-June-15, 10:06, said:

Just as a matter of courisity, if this is your set of rebids after 2NT, is it still appropriate to call 2NT Jacoby? The standard set of rebids is for the 3 level rebids other than the agreed suit to show shortness. At what point of modifying the rebids does 2NT stop being Jacoby and become a game forcing 2NT (not Jacoby)?

To resolve issues like this, I never use convention names when answering questions at the table. So for me, it would always be "game forcing spade raise" no matter what follow-ups are in use.
Life is long and beautiful, if bad things happen, good things will follow.
-gwnn
0

#7 User is offline   Bbradley62 

  • PipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 6,542
  • Joined: 2010-February-01
  • Gender:Male
  • Location:Brooklyn, NY, USA

Posted 2012-June-15, 10:21

ACBL Alert Procedures said:

PART X: DELAYED (or POST) ALERTS ALERTABLE CALLS ABOVE THE LEVEL OF 3NT STARTING WITH OPENER'S SECOND TURN TO CALL

Once the auction has progressed to the point that the opening bidder has had the opportunity to make a second call, conventional calls at the four level or higher are not Alerted until the auction is over.


These DELAYED ALERTS are REQUIRED to be made by the DECLARING side before the opening lead. The DEFENDERS are REQUIRED to Alert declarer AFTER the OPENING LEAD but BEFORE declarer makes a play from dummy (Alerting before the lead is turned face-up and the dummy is spread is best).

The declaring side must make their Delayed Alerts before the opening lead. Defenders wait until they have made the opening lead before they explain calls requiring a Delayed Alert. As with normal Alerts, the partner of the person making the Alertable call is the person who makes the Delayed Alert and explains the agreement.

EXAMPLES:

1-P-1-P 4 (splinter)
There is no Alert at the time for the 4 bid.
After the auction, the 1 bidder must Alert and explain as required the meaning of the call.

0

#8 User is offline   billw55 

  • enigmatic
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,757
  • Joined: 2009-July-31
  • Gender:Male

Posted 2012-June-15, 10:27

Bbradley, I read that too, before I posted. It sort of applies but maybe not. The question is, is 4 in my auction considered a "conventional call"? It is a natural signoff, but it carries additional meaning in context of the conventional 2NT call. Does that make it a "conventional call"? Perhaps.
Life is long and beautiful, if bad things happen, good things will follow.
-gwnn
0

#9 User is offline   Bbradley62 

  • PipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 6,542
  • Joined: 2010-February-01
  • Gender:Male
  • Location:Brooklyn, NY, USA

Posted 2012-June-15, 10:29

ACBL Alert Definitions said:

Convention: A bid which, by partnership agreement, conveys a meaning not necessarily related to the denomination named or, in the case of a pass, double or redouble, the last denomination named.
So, since 4 specifically tells you that partner has 2-4 clubs, 2-4 diamonds and 2-4 hearts, it is a conventional bid, not simply a natural one.
0

#10 User is offline   helene_t 

  • The Abbess
  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,199
  • Joined: 2004-April-22
  • Gender:Female
  • Location:Copenhagen, Denmark
  • Interests:History, languages

Posted 2012-June-15, 11:04

View Postbillw55, on 2012-June-15, 08:51, said:

On the next hand, after LHO opened and my partner passed, I (being a wiseguy) alerted and explained that pass denies holding 20+ points.

That pass denies 20+ points is expected so it should not be alerted. But if you mean that it could be as strong as 19, then it is probably alertable.

The expected meaning of a pass in the opening seat is something like "0-11, but not a nice distributional 10/11, nor a hand suitable for a normal preempt". If your style deviates significantly from that, for example if you open a weak two with any 0-10 count with a 5-card suit, then maybe the pass becomes alertable.
The world would be such a happy place, if only everyone played Acol :) --- TramTicket
0

#11 User is offline   barmar 

  • PipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Admin
  • Posts: 21,594
  • Joined: 2004-August-21
  • Gender:Male

Posted 2012-June-15, 15:22

View Postbillw55, on 2012-June-15, 10:27, said:

Bbradley, I read that too, before I posted. It sort of applies but maybe not. The question is, is 4 in my auction considered a "conventional call"? It is a natural signoff, but it carries additional meaning in context of the conventional 2NT call. Does that make it a "conventional call"? Perhaps.

The ACBL Alert Procedure calls this a "treatment":

Quote

A treatment is a natural call that carries a specific message about the suit bid or the general strength of the hand.

Although it doesn't specifically mention implications about distributions of other suits (i.e. no shortness), I think this can be considered part of "general strength". Treatments are only alertable if they have unexpected meanings (despite their popularity, the document specifically mentions weak jump shifts as being "unexpected" -- the problem with listing specific agreements is that a document can easily become out of date).

But if you don't agree with my interpretation, there's also this clause:

Quote

In general, when the use of conventions leads to unexpected understandings about suit length by negative inference, a natural call becomes Alertable. Some such agreements have become expected and are fairly common, therefore no Alert is required.

(Highlighting from the original.) So the question is whether this agreement about rebids after Jacoby is common enough that it has become expected. The examples they give are 1-1 promising 5 spades when playing Flannery, and bypassing diamonds to bid a major over 1; I'd argue that Jacoby 2NT with its standard rebids is at least as popular as Flannery, so the negative inferences are not alertable.

However, since this bid is above 3NT and is opener's second bid, if it's alertable it would be a delayed alert. Since there's no UI from a delayed alert, there's little reason NOT to clarify it after the auction is over.

#12 User is offline   Mbodell 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,871
  • Joined: 2007-April-22
  • Location:Santa Clara, CA

Posted 2012-June-16, 00:33

You definitely don't need to give the immediate alert because of the above 3nt and openers second call (and not a conventional X or pass which do still need an alert even above 3nt) reason. I'm not sure you'd need a delayed alert, since it seems common and expected, but full explanations rarely hurt.
0

#13 User is offline   Vampyr 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,611
  • Joined: 2009-September-15
  • Gender:Female
  • Location:London

Posted 2012-June-16, 07:45

View Postjh51, on 2012-June-15, 10:06, said:

Just as a matter of courisity, if this is your set of rebids after 2NT, is it still appropriate to call 2NT Jacoby?


Convention names are never appropriate.
I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones -- Albert Einstein
0

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

2 User(s) are reading this topic
0 members, 2 guests, 0 anonymous users