[mike777]

Winstonm, on May 3 2006, 06:16 AM, said:

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

ya on that auction you pretty much have to X to give partner a chance to bid 3nt.
If she cannot bid 3nt or pass your x then you make your best guess of 5-3 minor or 4-3 heart fit. NFB is not perfect, you just see if you can live with the tradeoffs.

[han]

Stephen, you are not doing yourself a favor by claiming that you (or anybody) can show that a treatment of NFB is better than another by running a bridgebrowser analysis. The analysis completely ignores the treatments the pairs use!

Bridgebrowser is a great program that is extremely helpful to gain a better understanding of bridge. For instance, there have been many searches that Ben has posted on this forum that showed us what hands we should expect for a certain auction. It is not hard to imagine many other advantages of a program that uses bridge hands that have been played by real people instead of double dummy analysis.

But by making such claims that are clearly false to anybody that takes the effort to think about it, both you and your program lose credibility. At least in my eyes.

[sfbp]

Ben made one point: that the 2H bid by a passed hand is nonforcing. I'll check that asap.

But it's a pretty good bet that if an unpassed hand bids 2H and it goes P P that the agreement is Negative Free.

Heck i got messed up when someone from Eastern Europe (pick up pd) insisted that 2S free was weaker than double. So it's not as rare as you think, either.

[joshs]

sfbp, on May 2 2006, 08:10 PM, said:

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

Stephen, Can you please explain how this was demonstrated?

I am certain that if 1C-P-2H showed 7-8 HCP and a 6 card suit to 1 or 2 top honors your game bidding over that will be very accurate. So I want to know exactly what the study was, and what the methodology was.

I am equally certain that if one partner plays 2H as 0-6 and the other partner plays it as 4-7, their bidding accuracy will not be much better than when one partner thinks they are playing a 15-17 NT and the other partner thinks its a 12-14 NT.

My one statistical claim is that the % of highly edjucated people who can devise a basic statistical test correctly, is very small.... Its very sad but true. I made a living for many years explaining basic statistics to engineers at NASA and those working for the DOD...

This has been demonstated repeatedly on this forum by proposed used of bridge browser data to prove various things that the proposed test didn't even come close to proving or measuring....

[sfbp]

Quote

I am certain that if 1C-P-2H showed 7-8 HCP and a 6 card suit to 1 or 2 top honors your game bidding over that will be very accurate. So I want to know exactly what the study was, and what the methodology was.

I am equally certain that if one partner plays 2H as 0-6 and the other partner plays it as 4-7, their bidding accuracy will not be much better than when one partner thinks they are playing a 15-17 NT and the other partner thinks its a 12-14 NT.

Sure I will redo it immediately.

Bottom line, when JS was made with 7+ it got bad results.

[sfbp]

It actually doesn't matter what the response shows.

I checked.

If you have more than 6 points when you make a weak jump shift (over pass by opp), you get a negative score. Period.

Stephen

[Stephen Tu]

I don't understand your methodology. How do you filter out people who think they are playing 5-8 when their partners think they are playing 0-6? How do you filter out people who are playing wjs when partner thinks they are playing strong jump shifts?

It sounds like you are just looking at the total score of hands that made a jump shift with that point range. That tells you nothing about whether the cause of the bad results was lack of partnership agreement, or because it actually is a poor treatment. It also tells you nothing about gains from negative inference on hands when it is not used. There is nothing here to support your conclusion that wjs with moderate hands is a bad treatment. I think everyone agrees that playing a different range from what partner expects would be problematic.

How about looking only at hands where opener passed the 7-8 pt wjs with <= 15pts, < 4 cd support? This would at least look at a subset of valid results, and filter out some people with range discrepancies. Although it still wouldn't lead to any real conclusion about the overall effectiveness of the method.

[sfbp]

Who cares what was in their minds?

Who cares if they were on the bottom end of one range or the top end of another?

There is more to making a result than the two players and what they thought each other's bid means. These results are what happened under the stated conditions. I've already built a bidding system from this and many other results like them.

At any moment in time, a player takes an action in a similar situation based on his hand and a set of circumstances. Playing 2NT contracts is a heavy loser. I don't need to explain WHY in order to believe that it is. However armed with my belief I will attempt to play to better scores by avoiding it except when there is no alternative.

Correct me if I am wrong - but your argument appears to be that any treatment, if played correctly is capable of the best score?

Stephen

[Stephen Tu]

Quote

Correct me if I am wrong - but your argument appears to be that any treatment, if played correctly is capable of the best score?

No, my argument is that you can't use Bridgebrowser data in an entirely too simplistic fashion to make sweeping blanket statements about the efficacy of a treatment, when there are significant variations in the way the treatment is played, and the data is coming from a pool where a lot of the results are from pickup partnerships where there is little system discussion. It is impossible to conclude whether the poor results are the result of range expectation mismatches, or if the treatment itself is really a loser.

Look through a bunch of your results board by board. I am sure you will find hands where opposite a 7-8 wjs, opener despite a very strong hand passed, expecting much a much weaker hand from responder. I am sure you will also find hands where opener despite a weak hand bids on, probably expecting a strong jump shift. Basically, a lot of your data is garbage, therefore your conclusion may also be garbage.

I won't dispute that if you make weak jump shifts on 7-8 pts and partner expects a significantly weaker range that you can miss games and will get poor scores. But I find it hard to believe that a regular partnership that is in sync on a tightish range of the bid would lose significantly on these hands.

The only thing I am sure of is "avoid jump shifting with a pickup partner".

[42]

inquiry, on May 1 2006, 10:43 PM, said:

Hannie, on May 1 2006, 03:21 PM, said:

I don't play negative freebids, mostly for the reasons Mike gave. I have tried them in the past and found that double becomes too heavy.

I do play transfers in some limited situations right now. With Ben I used to play much more extensive transfers in competition. I think that "equality" is a theoretically superior method than negative freebids, but I found the memory load to be too heavy. If I was to form a regular face to face partnership with a partner who likes these methods too, then I would consider adopting equality again.

equality has some huge downsides as well...

I am happy with Switch, as you described in your PDF.. Maybe you should post that here.

Hi!
I now have some additional questions:
- what is switch?
- how works "equality"?
- what are the main advantages of playing transfers? Is a negative double out? If so, how do you show a hand with both open suits? Is the range for transfers only 6+ pts? What do you do later when 4th man preempts and you have a GF hand? I think I did not yet get the idea of transfers (= being a 4+ or 5° suit?)

[hotShot]

The main advantage of playing transfer is, that the weak hand gets dummy.
You know in Rieneck-Standard the sequence:
1m - 2M
where 2M is a NFB.
Bridgebrowser results indicate hat 2M should have 6+cards and 6-HCP.
Using transfer would not change the hand, but the bidding would be:
1m - 2(M-1)*
2M*
* transfer
(M-1)=♦ => M=♥
(M-1)=♥ => M=♠

[42]

hotShot, on May 4 2006, 11:39 AM, said:

The main advantage of playing transfer is, that the weak hand gets dummy.
You know in Rieneck-Standard the sequence:
1m - 2M
where 2M is a NFB.
Bridgebrowser results indicate hat 2M should have 6+cards and 6-HCP.
Using transfer would not change the hand, but the bidding would be:
1m - 2(M-1)*
2M*
* transfer
(M-1)=♦ => M=♥
(M-1)=♥ => M=♠

I know in general the advantages of transfers and how to bid them But I do not know the specific requirements in this special situation (after intervention). It is easy to see (even for me) that it must be good with a weak 6° suit, but how does the bidding proceed when responder is intermediate/strong with 4-6 cards?

[helene_t]

There is a description of Equality on Daniel's System Pages

[Gerben42]

There are a lot of gains of 5 - 8 jump shifts when you don't bid them, so in a way it is hard to measure anyway...

I agree with being careful with jump shifts opposite a pickup partner.

[cherdano]

42, on May 4 2006, 10:54 AM, said:

Hi!
I now have some additional questions:
- what is switch?
- how works "equality"?
- what are the main advantages of playing transfers? Is a negative double out? If so, how do you show a hand with both open suits? Is the range for transfers only 6+ pts? What do you do later when 4th man preempts and you have a GF hand? I think I did not yet get the idea of transfers (= being a 4+ or 5° suit?)

About negative double: when we (Ben, Han, Matt, me) were toying with various ideas about transfers in competition, we learned to be very reluctant to give up negative double (especially when there is exactly one unbid major). You can't afford not to find 4-4 major fits, but bidding (or transferring into) the suit directly on 4-cards is very dangerous when it consumes space. Negative double is really a great bid!

About switch: an example auction is 1♦-(2♠), where we play 3♣ as showing hearts, a good NFB or better, and 3♥ as showing clubs, GF. Compared to standard (non-NFB) methods, you lose two steps when you bid 3♥ instead of 3♣, but you gain both a bit of space and the ability to show both a NFB-type or a GF hand when you have hearts.

I think it works well, but it doesn't come up very often. (We only play it when there is exactly one unbid major and the opponents overcalled 1-3♠ or 2-4♣.)

Arend

[cherdano]

sfbp, on May 4 2006, 07:02 AM, said:

Who cares what was in their minds?

Who cares if they were on the bottom end of one range or the top end of another?

There is more to making a result than the two players and what they thought each other's bid means. These results are what happened under the stated conditions. I've already built a bidding system from this and many other results like them.

At any moment in time, a player takes an action in a similar situation based on his hand and a set of circumstances. Playing 2NT contracts is a heavy loser. I don't need to explain WHY in order to believe that it is. However armed with my belief I will attempt to play to better scores by avoiding it except when there is no alternative.

Correct me if I am wrong - but your argument appears to be that any treatment, if played correctly is capable of the best score?

Stephen

Stephen, your logic is fundamentally flawed. How many of the partnerships playing in MBC do you think have discussed what to expect from a WJS? (Assuming, they have agreed whether they are playing WJS or SJW at all....) My guess would be around 1%, maybe even less. Do you really think the results these partnerships achieve on average with a 7pt WJS are convincing to show that 4-8 hcp WJS with good discussion are better than 0-6 hcp WJS with good discussion?

Do you really still believe your methodology when it seems to indicate a treatment (0-8 NFBs) that no top player at all is using?

Han's point about credibility is exactly on the mark.

Arend

[whereagles]

There's some logic in trying transfer responses after overcalls. I myself devised a couple of transfer gadgets after 1x (1y), 1x (dbl) and even up to 1M (2M-2).

However, it is my experience that natural methods are perfectly fit to deal with most situations. The occasional gains of transfers do not compensate for the memory load.

[inquiry]

cherdano, on May 4 2006, 06:05 AM, said:

sfbp, on May 4 2006, 07:02 AM, said:

Who cares what was in their minds?

Who cares if they were on the bottom end of one range or the top end of another?

There is more to making a result than the two players and what they thought each other's bid means.  These results are what happened under the stated conditions. I've already built a bidding system from this and many other results like them.

At any moment in time, a player takes an action in a similar situation based on his hand and a set of circumstances. Playing 2NT contracts is a heavy loser. I don't need to explain WHY in order to believe that it is. However armed with my belief I will attempt to play to better scores by avoiding it except when there is no alternative. 

Correct me if I am wrong - but your argument appears to be that any treatment, if played correctly is capable of the best score?

Stephen

Stephen, your logic is fundamentally flawed. How many of the partnerships playing in MBC do you think have discussed what to expect from a WJS? (Assuming, they have agreed whether they are playing WJS or SJW at all....) My guess would be around 1%, maybe even less. Do you really think the results these partnerships achieve on average with a 7pt WJS are convincing to show that 4-8 hcp WJS with good discussion are better than 0-6 hcp WJS with good discussion?

Do you really still believe your methodology when it seems to indicate a treatment (0-8 NFBs) that no top player at all is using?

Han's point about credibility is exactly on the mark.

Arend

To be fair to stephen, he is not using main bridge room hands here, but rather some very old okb data because there is a lot more hands in that database. I think the data is from 1997 to 2001 time range.

I think there is a reason that higher hcp on 1x-p-2y is worse. Opener has 11+, lets say average of 14 (guess) and responder has some number. If he has "too much" his preempt prevents his side from finding the best spot when the hand BELONGs to his side. I think a study might be to hold the suit to some minimum quality and lenght and check the results with 4,5,6,7,8,9 pts including bids like pass, simple bids and jump to different levels.

this does address a lot of issues (which is the best winning strategy, for example, weak jump shits, strong jump shift, fit jumps, interemediate jump shifts), but it will demonstrate trends on what happens with minimum quality suit and minimum points based on what you bid. And this is easy with bridgebrowser.

[Codo]

inquiry, on May 4 2006, 08:34 PM, said:

.... ( for example, weak jump shits)

I am quite interessted in this new tool, may you explain me your new concept please?

[hrothgar]

sfbp, on May 4 2006, 08:02 AM, said:

Who cares what was in their minds?

Who cares if they were on the bottom end of one range or the top end of another?

The short answer to your question is "Anyone with a halfway decent understanding of statistics"

There is a big difference between statistical analysis and data dredging. Unfortunately you don't seem to want to understand the distinction.

As an analogy: If you applied the same methodology to studying a Precision style 1C opening I'd by 90% sure that your analysis would show that no one should ever play a strong club. After all, any time that you open a strong club your expected score is significantly worse than any other bid in the system. Equally significant, the strong club opening often isn't as accurate as the "natural" bidding styles that most players use. Needless to say, this analysis would be badly flawed. The poorly defined 1C opening is a systemic cost of the light / limited openings bids that comprise the rest of the system. You can't analysis one piece without the other. Unfortunately, your making precisely this same type of mistake.

Please understand: I'm not knocking BridgeBrowser. Its a great product. Used correctly, you can shed light on a lot of interesting questions. But your not doing so here. Moreover your blind insistence that you are undertaking valid analysis doesn't do you or your product any good.

From my perspective, I think that you should starting by analyzing some very basic questions. For example, you might want to consider looking at board results are seeing whether there is a relationship between the expected score that a given player achieves on boards and the variance of their scores.