[Sigi_BC84]

Chamaco, on May 2 2006, 01:59 PM, said:

2. Transfer response after a 1-level overcall

Can you describe your methods in more detail? I would be interested.

--Sigi

[mike777]

For those of you who often play NFB how do you play?

1C=(2D)=2H or
1C=(2D)=3H

[Gerben42]

Quote

1C=(2D)=2H or
1C=(2D)=3H

First NF, second natural and GF.

[Cascade]

mike777, on May 3 2006, 09:37 AM, said:

For those of you who often play NFB how do you play?

1C=(2D)=2H or
1C=(2D)=3H

2♥ = around 6-11 hcp with (5)6 ♥s

3♥ = GF and distributional and at least mildly slammish with six ♥s

4♥ = Nat to play - worse than 3♥

[luke warm]

mike777, on May 2 2006, 04:37 PM, said:

For those of you who often play NFB how do you play?

1C=(2D)=2H or
1C=(2D)=3H

2h=7-11, nfb
3h=5pcs with 4p clubs in a gf hand...

[sfbp]

Quote

I certainly don't play NFB the way Stephen describes.
The NFB partnership plays 2M as a sort of 'textbook' weak two, albeit possibly a 5-card suit. Vulnerable, something like KQ109xx with nothing outside would be an absolute minimum. There are quite a lot of hands where I'd bid 2M whether it's forcing or not (but then even when I play 2M as forcing, it's not as strong as mikeh plays it).

I think it was a while ago that someone (Carl Hudecek) did the work to establish that weak jump shifts by responder (usually of 2♠ or 2♥ over a std opening bid) in direct response without intervention work best when they are REALLY weak, in the 0-6 range. Otherwise the partnershp misses game too often. Your example hand is still well within those parameter, Frances.

I view this (2-level NFB) bid as an extension of that. It gives us the ability to play in our assumed 6-2 fit (a priori it's probable that pard has at least doubleton in unbid suits) at the 8-trick level, something that Larry and LOTT and Vernes tell us should be right.

Because of the intervention by opp we are able to make it on a bunch of hands where we were previously denied that privilege, and where frequently(unless opps are "smart" enough to overcall on bad 8 or 9 counts at the 2-level) it is in our best interest since opps promise an opening hand when they overcall in a minor. Sort of like the principle of support X - we have three bids instead of 2 available because they intervened.

Don't make it too constructive, or you confuse your par with overall par. There are some bids at the top of the range where for various reasons you make a NFB, and pray that you weren't too strong. Similar to the idea that when you overcall against 1NT, the better your hand the better it is to pass and defend.

When you don't have a 9 or 10 card fit with partner, the opponents cannot preempt you out of much.

What we concluded (this at the table, not in the datamining) is that if he does have a 10-card fit with your nfb, you shouldnt get too wild - most of the time you are pushing them into game instead of playing in your undoubled advance "sacrifice" at the 2 level when the hand is weaker. It's only when he has a rockcrusher in terms of HCP that he should support you to game.

Stephen

[Winstonm]

I haven't read all the posts as to not be influenced by others - I do not play negative free bids for a simple reason which is the bonuses in bridge are paid for game and slam bidding, not in precise partscore bidding. The hand that can get screwed to tears by opponents' preemptive action is the game forcing hand that needs a little room to help clarify - if I give the opponents the chance to preempt behind my forced double (what I must do with a good hand), then I've cheated myself out of a descriptive round of bidding.

That being said, I do pay homage to the the concept of not getting shut out, even when playing 2/1, by adopting standard Goren-ish 2/1 when RHO interferes, dropping the free bid requirements to around 11. And yes, every now and then I lose the heart suit when I have 9 and partner happens to hold 3 and we could have made 3H.

Nothing is perfect.

Winston

[FrancesHinden]

sfbp, on May 3 2006, 02:10 AM, said:

I think it was a while ago that someone (Carl Hudecek) did the work to establish that weak jump shifts by responder (usually of 2♠ or 2♥ over a std opening bid) in direct response without intervention work best when they are REALLY weak, in the 0-6 range. Otherwise the partnershp misses game too often.

I'm sorry, I simply don't believe this is true as you have stated it.

The more strength you have, the more likely you are to have game on. It simply cannot be true that you need to play WJS as 'really weak' otherwise you 'miss game too often'.

I only believe this statement if you tack on ....because opener is forced to pass your WJS/NFB.

But my partner is allowed to make game tries opposite a WJS or NFB.

[Winstonm]

I have a question for all the NFB enthusiasts. If I understand them correctly - I only tried them for a very short time years ago at mps - the strong hand has to start with double. So, Qx, Axx, xxx, AKJxx after 1D-1S should first double. Now when the auction continues: 1D-1S-X-3S-P-P-? What am I to do? If I double how does partner continue with Kxx, QJxx, AJxx, Qx or x, Axxx, KQJxx, Qxx?

However, I admit that the auction: 1m-2H-2S might be best used as a NFB, as with spades and a good hand I can double and later on bid spades. I understand the frequency issue, but being able to bid freely on 7 or 8 points to me is not a big issue if you drop the requirements in competition of a 2/1 being a 1-round force only. That allows you to still bid with the 10-11 point hand.

Winston

[sfbp]

Quote

The more strength you have, the more likely you are to have game on. It simply cannot be true that you need to play WJS as 'really weak' otherwise you 'miss game too often'.

I only believe this statement if you tack on ....because opener is forced to pass your WJS/NFB.

But my partner is allowed to make game tries opposite a WJS or NFB.

Believe it. It's a raw measurement. If you analyse what happens by point count, the better the responding hand, the worse the overall result.

You can interpret it any way you like; so can I. But in terms of imps/matchpoints outcome, when WJS gets too strong, you lose.

It's harder to provide this for NFB, because I have only my experience as the guide unless I can separate out the folks who play NFB as non-constructive. Here's a start.

From the large dataset, 24 million hand records, the bidding started with a 1 spade overcall (of a minor opening) 11,332 times over 806 boards, when responder held a maximum of 8 HCP, and any of the following holdings in hearts:

KJxxxx, KQxxx, KQJxxx,Axxxxx,AJxxxx,AQxxxx

Of course I cant filter out precision/polish, but this the OKB dataset 1998-2001 and I promise you there aren't many playing non-standard in the mix there. (6778 times after 1D, 4554 times after 1C might appear to confirm this)

Constraining the bidding to 1m (1S) 2H (5929 times) gave by far the best outcome (+1.8 imps, or 65%, 296 times with reasonable SEM's) when opener passed (with our without double by the opps), with the HCP count for the partnership peaking at 20, and barely touching 25. So that appears to confirm my table experience, and the theory about not wanting to be in game.

The most frequent outcome of the 2H bid was 4S by the other side (of course on these hands it was anyway), for a reasonable plus (+0.80/50.8%) to the opposition - so the ability of our side to play in 2H was likely affected by the decision of the opponents to pass. But that wasn't known when opener passed the NFB, and the 1S overcaller still had a chance to act again. The most frequent contract by our side was 4H (+0.29/54%). I can't tell what their agreements were.

Interestingly a signficant contribution (1/3) to the success of passing the NFB came from playing 2HX

I'm sure there's more there, but this is a start.

Stephen

[Chamaco]

sfbp, on May 3 2006, 12:38 PM, said:

Constraining the bidding to 1m (1S) 2H (5929 times) gave by far the best outcome .......
SNIP

This specific sequence deserves a discussion.

After: 1m (1S) 2H
playing NFB, when responder holds a GF hand with 5+ hearts, is better handled by cuebidding 2S so to show GF with 5+ hearts before opps can bouce to 3-4S.
This is better than doubling, and reduces considerably the vulnerability to overcalls.

There is somewhat less vulnerability to opps bouncing when they overcall 2m because a minor is lower ranked than our major.

[Codo]

Stephen, I don`t get it:

Your data base confirmed, that it is best to pass 2 Heart as opener, if responder is limited to 8 HCPs? This does not sound very surprisingly to me yet.
Passing with a marginal opening hand opposite a limited opener seems to be a good thing and had been known even without your datas.

The issue is: Should you bid NMF with a range "0-7" "8-10" "11+" and we have mayn opinions, but no clear majority. So maybe anything is fine....

[sfbp]

Quote

Your data base confirmed, that it is best to pass 2 Heart as opener, if responder is limited to 8 HCPs? This does not sound very surprisingly to me yet.
Passing with a marginal opening hand opposite a limited opener seems to be a good thing and had been known even without your datas.

Right. And you also pass preemptive openings by partner on bad hands, yes?

The point is, if responder could have been constructive, might not opener have raised? Very likely the cases where opener passed, he *knew* responder was weak, presumably by agreement.

sfbp

[Chamaco]

sfbp, on May 3 2006, 02:38 PM, said:

The point is, if responder could have been constructive, might not opener have raised?  Very likely the cases where opener passed, he *knew* responder was weak, presumably by agreement.

Yes, this is an important point where precise agreements are needed.

Here are mine:

1- NFB on for Precision 1D opening, limited and unbalanced (12+/15 balanced shall open 1NT even with 5 diamonds).
NFB does not apply for 1M openers, nor after 1-level overcalls.

2- Responder is always constructive/invitational. A NFB is never made just as a shutout bid.

3- SPECIFIC ABOUT THIS ISSUE Opener is virtually forced to raise if he has a 3+ card fit (unless 4333) even with minimum hands.
In the worse case scenario we are most often at a LOTT-compliant level (most often the NFB will be a 6+ bagger, so with a 3+ support, we have a 9 card fit, often resulting in the right partscore even if both opener and responder are light)

This last point allows one more round of bidding to responder if he has indeed a good hand.
Indeed, such scheme seems to hit quite a few marginal game contracts (21-23 hcp)that are on a finesse at most.

4- One last agreement is that opener shall pass virtually any hand with less than 3 card support, with few exceptions (Hx support AND max hcp content, or selfsufficient own suit)

[Stephen Tu]

Quote

Believe it. It's a raw measurement. If you analyse what happens by point count, the better the responding hand, the worse the overall result

I'd really distrust any analysis done by Carl Hudecek. He has repeatedly shown an inability to do accurate mathematical analysis; he doesn't even understand restricted choice.

Bad results by relatively high pt count WJS responses can easily be explained by one partner assuming the ultra-weak 0-5 American variety (thus almost never trying for game), while another using the European 5-8 semi-constructive variety (w/ more frequent game tries). Using BridgeBrowser to just analyze these things in bulk can't tell you whether the bad results are due to it being a bad idea to WJS with 8hcp or if it's just pickup partnerships playing different styles.

Even if WJS with the 8 hcp loses in general, with both partners in the know (there certainly will be losses in making a game try & going down 1 at the 3 level), the semi-constructive style could be more effective style overall (much more frequent, benefits in 1/1 auctions when not used). See Hannie's "Bridgebrowser challenge" thread, it is hard to use the data to definitely say one treatment is definitely better than another.

As for NFB, I have never liked them because I think the losses when you have a strong hand and have to double are more frequent & larger in magnitude than the gains you get when you make the NF bid. I have no quantitative data to back this up, just memory of many auctions where opps playing NFB fixed themselves by not being able to show all features of their hand starting with the double (w/ advancer of overcaller just making a single raise) at the critical level below 3nt, with almost no memory of opps fixing us by making a NFB & reaching a good contract the field could not reach.

[sfbp]

Well I did it too and confirmed the results.

You can't gainsay it "just because it was Carl"

Anyhow the point is you missed all the hands that I would have bid 2 of a suit on because by many peoples standards they are simply too weak. Those don't show in your analysis. All you remember is the doubles?

Stephen

[jdonn]

sfbp, on May 3 2006, 02:04 PM, said:

You can't gainsay it "just because it was Carl"

Yes you can. Stephen (other one, not you) was being kind, if anything. I remember very clearly back from my okbridge days that any analysis CH performed by gathering large amounts of data were completely untrustworthy for many reasons. He consistently failed to account for many factors, some of which were obviously present. He has shown himself time and time and time again to have absolutely no idea how to conduct statistical studies and analyses.

Of course that doesn't mean any conclusion he reaches must be wrong, just that his studies give no evidence of a conclusion pointing in any direction.

[Cascade]

We have some special but simple treatments for the auctions 1m (1♠)

Quote

So, Qx, Axx, xxx, AKJxx after 1D-1S should first double.

We bid 3♣ forcing (to game) with this hand. These are the only auctions where we have to jump with a relatively flat hand. However we also have 2NT and 3NT natural available which we can bid with the other minor and a good stopper.

Quote

QUOTE (sfbp @ May 3 2006, 12:38 PM)
Constraining the bidding to 1m (1S) 2H (5929 times) gave by far the best outcome .......
SNIP 


This specific sequence deserves a discussion.

After: 1m (1S) 2H
playing NFB, when responder holds a GF hand with 5+ hearts, is better handled by cuebidding 2S so to show GF with 5+ hearts before opps can bouce to 3-4S.
This is better than doubling, and reduces considerably the vulnerability to overcalls.

There is somewhat less vulnerability to opps bouncing when they overcall 2m because a minor is lower ranked than our major.

We still play a cue-raise here. But we play double shows (100%) hearts - 4+. The weak hands with long hearts are unloaded out of the double we can make a negative free bid of 2♥ as are strong distributional hands with 6+ hearts where we can jump to 3♥.

Of course we are worse off when the 5-card heart suit hand turns up but we have better definition on some other hands. So far we have been happy with this compromise.

[inquiry]

I love Bridgebrowser, and have many hours of enjoyment messing with it each week. Having said that, there ARE limitations to what you can do with it. The Negative Free Bid concept seems one of them to me. Let's see if we can see what it is SFBP is doing and what is right and more importantly what is wrong with is approach.

I think he does this...

1) defines opener as bidding 1m (easy enough)
2) gives a 1♠ overcall (easy enough)
3) gives responser from "0" (well never 0) to 8 hcp and a sxi card heart suit headed by either the ACE or any two of the top five honors. This pass doesn't seem to matter if rho dbls or not.

Then he looks at the result where the OPENER passed the 2♥ bid (by definition, then 2♥ was not forcing, hence in this logic a negative free bid). The fallicy in his logic are multi-fold.

1) On many "negative free bid hands" opener rebids, he disregards those hands, self choosing ones where opener is weak.

2) Many of the 2♥ calls were made NOT in the context of a negative free bid, thus opener at those tables will bid on. This "bad bidding" at one table thus rewards the cautious pass at the tables he is looking at.

3) He doesn't mention rahter he controlled for opener being 3rd or even 4th seat.

4) His description of fpr a negatve free bid is probably not all that standard, many will have five card suits, and with six, it is not clear two honors and broke elsewhere are useful.

I am not certain how to study negative free bids, but clearly opener "does best to pass regardless what his hand is" approach can not be right. There has to be at least a subset where passing is wrong.

For me, I don't like negative free bids except in one very limited context. Playing matchpoints and precision, then I don't mind negative free bids were frequency is the name of the game, and where when I am weak I am pretty darn sure we don't have game (unlless partner has distributional fit with me).

[sfbp]

This is a silly argument along the lines of All elephants are pink - this animal is pink, therefore it must be an elephant.

trust me, I did the math - it was correct

In any event maybe my recollection was faulty, probably I did the original search and Carl simply wrote it up. Or maybe I did it and never publish it.

IN ANY EVENT, it's true. I have had dozens of good players and several experts confirm that wjs need to be very weak to be effective. Not mentioning my own experience.

Get a life, Josh. Carl's middle initial is not G. Maybe he didn't do the math right sometimes... that's why many of the features of BRBR were added, to check things like standard deviations and distinguishing contracts by opener from contracts by non-opener.

Hope this finds you in better humour than it left me