Stayman with 44M less than invite

[bluecalm]

Interesting stuff, thanks for the link.

I tried some staymans like that recently but with mixed results I still wonder if passing with 4-4-3-2 after 2D might indeed better.

[rhm]

I don't get it with 4432. Instead of a (almost) certain 7 card fit, you would choose a fit that will (almost certainly) be anywhere from 5 to 8 cards?

 

It is close.

Some arguments for passing:

8 cards in diamonds are nearly 3 times more likely than 5 when partner admits to no major suit and a 7 card fit is also more likely than a 6 card fit.

If you have only a 7 card fit you have a ruffing value with your 3 card diamond suit. That is not guaranteed in a major. Opener will often be 4333.

When you are 0-5 with no good fit in a major, your objective should be to maximize your chances for any plus, not necessarily the highest one.

If you go down, there is no premium for going down in a major instead of a minor.

 

Rainer Herrmann

[gnasher]

I don't get it with 4432. Instead of a (almost) certain 7 card fit, you would choose a fit that will (almost certainly) be anywhere from 5 to 8 cards?

 

I think this has to be considered in the context of the rest of your Stayman structure. If you don't play 1NT-2♣;2♦-2♠ as a signoff, then you're probably already playing that opener gives preference after 1NT-2♣;2♦-2♥. Hence bidding this with 4=4 has no additional cost.

 

If, on the other hand, you play 1NT-2♣;2♦-2♠ as a signoff with 5=4, then 1NT-2♣;2♦-2♥ would currently be a signoff with 4=5. Adding 4-4 shapes would mean that opener had to give preference, so with 3=2 opposite 4=5 you'd reach what tends to be the wrong partscore.

[lalldonn]

Remember he is also bidding 2♣ then 2♥ with 4423. Also it seems (more than) a bit of a stretch to reach as little as a 5 card fit because you are worried that with one specific shape opposite another specific shape you will reach the worse of two 7-card fits.

[Statto]

Do you bid stayman? If the answer is "sometimes" what factors into your decision?

Usually the quality of the ♦ suit.

[Finch]

There are actually three questions here.

 

i) Is it a good idea to include very weak hands in the 2C response to 1NT i.e. hands that pass whatever opener's rebid?

ii) If you include very weak hands, is it a good idea to play that 1NT-2C-2D-2H is just scrambling and can be corrected to 2S by opener; or should 2H be to play (4-5 or possibly 3-5 in the majors)?

iii) If you include very weak hands, is it a good idea to respond 2C with 4-4 in the majors and 3 or fewer diamonds? If so, what do you do after 2D?

 

The discussion so far on the thread assumes that you play (i) (OK, that's obvious), but that you also play the first option in (ii) and are mainly discussing the answer to (iii).

 

As Free has observed, there are some good reasons not play play (i) at all: in one partnership we play that 2C guarantees invitational values. This allows you to stop in 2M much of the time you have an invitational hand with a 5-card major; it improves slam bidding; it improves choice-of-game auctions; it improves competitive bidding. Obviously there can be good results from bidding 2C on very weak hands, but it's a trade-off and it's not obvious which is better (in a strong NT framework in particular).

 

The most common 'English' approach to a weak 2C response is that you don't do it with 44 majors; 1NT-2C-2D-2H is to play in 2H. Traditionally it is a weak hand with 4-5 in the majors (and 1NT-2C-2D-2S a weak hand with 5-4) but it also works with, say, 3514 as 2S might well be a very good spot. It obviously works better if partner opens 1NT with a 5-card major every time he has one. So you might play some form of potentially weak 2C bid and still not want to do it with 4-4 majors.

[Finch]

I consider this a subject ideal for computer analysis Extensive results from double dummy analysis "Drop Dead Stayman" On what shapes and strengths is it appropriate?can be found at http://taigabridge.net/articles/dd/garbage.htmThe results indicate with few exceptions that those who do not pass are right much more often than not.To cite from the web site: "The two fundamental conclusions are having three cards in a suit is okay, but having only two is bad and the weaker responder's hand is, the larger the profit from using Drop-Dead Stayman." Rainer Herrmann

 

 

I didnt find what distributions were included in 1NT simulation......http://www.bridgebase.com/forums/public/style_emoticons/default/rolleyes.gifYu

 

 

Is it so difficult to read?QuoteIf you play very old-fashioned conservative 1NT openings -- especially if you rarely or never hold a 5-card major when you open 1NT -- you need to also be more willing to pass 1NTend-quote The extreme shapes in general (5422 etc) argue more for run-out than against it.Rainer Herrmann

 

 

I apologize for not repeating that clearly at the beginning of the drop-dead Stayman article; that was one of three articles on NT responses I wrote the same month, and more of the details are in the other articles. For the sim, opener's 1NT range was 15-17HCP. A 5-card major, 5422 pattern, or a 6-card minor is allowed. A singleton ace or king is not (always balanced or semibalanced.)As Rainer noted, I redid the results for a "classical" 1NT (15-17HCP, never more extreme than 5332, no 5-card major).I admit to being excited to know at least two people have actually read the article :)I have been 'practicing what I preach' since then, and getting raised eyebrows from partners for 2C on weak 3352s etc, but so far it has turned out reasonably well.A 4-3 fit does play better when you can ruff in the 3-card hand: that is a big reason why Stayman on 3352 or 3361 is a big winner, while with 4432 the case for running from diamonds to a 7-card major fit is not so compelling.

 

 

I'm surprised Rainer seems to miss exactly how important it is to specify exactly what a 1NT opening includes if you want to do this sort of analysis. Thanks to Siegmund for clarifying.

However, this simulation still only compares two possible strategies for opening 1NT:

 

(i) 4333, 4432 or 5332 with a 5-card minor

(ii) any 5422 or any 6322 with a 6-card minor {that's what the post says, although I don't know if you included 54 or 45 majors as a possibility}

 

We play

4333, 4432, 5332 with a 5-card minor, 6322 with a 6-card minor, 2425, 2452, or 2245 min.

This makes the chance of finding a better major suit fit much worse than either simulation for us.

 

I know what we play isn't that common, but a lot of people seem to play any 5332 allowed but only rarely a 6-card minor; for them 2C is more likely to get to a good contract. Similarly if you allow any hands with a singleton, 2C will be more successful.

[Mbodell]

I'm surprised Rainer seems to miss exactly how important it is to specify exactly what a 1NT opening includes if you want to do this sort of analysis. Thanks to Siegmund for clarifying.

However, this simulation still only compares two possible strategies for opening 1NT:

I know what we play isn't that common, but a lot of people seem to play any 5332 allowed but only rarely a 6-card minor; for them 2C is more likely to get to a good contract. Similarly if you allow any hands with a singleton, 2C will be more successful.

 

I agree. Assumptions about 1nt bids are very, very important for any sims of that auction, but especially important for this weak majors hand. I tend to open 1nt with nearly any (adjusted) in range hand with 4333, 4432, 5332, 5m422, 6m322 and very very rarely any other shapes.

[rhm]

I agree. Assumptions about 1nt bids are very, very important for any sims of that auction, but especially important for this weak majors hand. I tend to open 1nt with nearly any (adjusted) in range hand with 4333, 4432, 5332, 5m422, 6m322 and very very rarely any other shapes.

I understand you (and Frances) are great believers in David Burn's Law of Total Trumps:

 

"When you are declarer, the total number of trumps held by your side should be greater than the total number of trumps held by your opponents."

 

And believe it or not I also believe in David Burns complex theories. :rolleyes:

Nevertheless it is "very, very important" to understand that Bridge is a game of probabilities and this is what simulations are good at.

If I get time and again into a vastly superior partial, I do not mind if as a consequence I violate Burn's law of Total Trumps every second leap year. The trade-off is just too good.

 

Dogmatic fears can be exaggerated. Simulations help to put them in proper place

 

My experience with simulations are:

No matter how careful and conservatively you specify your assumptions, there will always somebody come along and doubt them, because he does not like the result.

When you then rerun the simulations with the modified specifications the average trick taking result changes 2 or 3 places behind the decimal point.

 

Rainer Herrmann

[gnasher]

My experience with simulations is:

No matter how many times you point out the inherent flaws in double-dummy analysis, the simulator continues to believe his findings implicitly, because he likes the idea that his simulation can substitute for experience. He rarely tells you what the exact criteria were, and is seems affronted when you ask for them. And he never ever provides any actual hands.

[rhm]

My experience with simulations is:

No matter how many times you point out the inherent flaws in double-dummy analysis, the simulator continues to believe his findings implicitly, because he likes the idea that his simulation can substitute for experience.

No they of course do not substitute for experience, but simulations complement experience, sometimes ideally, in particular when they have been set up carefully.

Experience is limited, and biased, because our mind remembers triumph and disasters and forgets run of the mill.

Our mind is not a rational robot, what we store in our memory is biased and invariably associated with emotion and there are very good reasons why our brain works like that.

Simulations can sample number of hands you will never hold in your lifetime. In that sense it is much more precise and it treats every deal the same.

 

He rarely tells you what the exact criteria were

I invariable do, when I report on my own simulations.

 

And he never ever provides any actual hands.

I rarely do, because reporting a sample from samples is bias, with which you can prove anything you like.

When I do, I try to convince myself that the hand is really representative for the total sample.

What matters is the overall result and that is statistical, average and variance being important.

 

Double Dummy is no substitute for single dummy. However, whatever the flaws are, it has been shown that over a large sample the results come surprisingly close to actual table results.

 

Rainer Herrmann

[cherdano]

Double Dummy is no substitute for single dummy. However, whatever the flaws are, it has been shown that over a large sample the results come surprisingly close to actual table results.

 

Has this also been shown for 4-3 fits in a partial?

[rhm]

Has this also been shown for 4-3 fits in a partial?

I am not aware that this particular issue has been researched specifically.

However millions of deals played have been researched and differentiated according to contract level and whether played in a suit or in notrump.

 

There were certainly plenty of 4-3 fits in partials when lower-level suit contracts were researched.

Double dummy makes very slightly less tricks (About 0.1 tricks at suit contracts below game level).

 

Rainer Herrmann

[gnasher]

I rarely do, because reporting a sample from samples is bias, with which you can prove anything you like.

When I do, I try to convince myself that the hand is really representative for the total sample.

I've just written some code. I know what it's supposed to do, I'm expecting it to work, and the compiler seems to like it. However, one of the things I'm going to do is to run it, look at some of the results, and compare them to what I'm actually trying to achieve. I think most writers of software would regard that as a normal thing to do.

 

If I were doing a double-dummy simulation, I would do the equivalent: I'd look at some of the hands, and consider (a) whether they were consistent with the auction I was trying to simulate, and (b) whether the double-dummy results were consistent with real-life expectations. If I were trying to persuade somebody else that my double-dummy simulation accurately modelled real-life bridge, I would invite them to do the same. I don't really understand the rationale for not doing this.

[steve2005]

Interesting idea. However, I will frequently bid 1N on 22(45) or even 22(36) distribution. 2♥ wont be fun opposite either of these hands. With 5-7 hcp surely 1N will be a playable spot. With 0-4 hcp opp might double then you can use rescues to get to best spot(maybe)

 

I think 2♥ is more useful as an invite with 5♥4♠ after 1N-2♣. Also 2♠ would be an invite with 5♠4♥ With a constructive use, i don't think a bid that may or may not help is advised.

[rhm]

I've just written some code. I know what it's supposed to do, I'm expecting it to work, and the compiler seems to like it. However, one of the things I'm going to do is to run it, look at some of the results, and compare them to what I'm actually trying to achieve. I think most writers of software would regard that as a normal thing to do.

 

If I were doing a double-dummy simulation, I would do the equivalent: I'd look at some of the hands, and consider (a) whether they were consistent with the auction I was trying to simulate, and (b) whether the double-dummy results were consistent with real-life expectations. If I were trying to persuade somebody else that my double-dummy simulation accurately modelled real-life bridge, I would invite them to do the same. I don't really understand the rationale for not doing this.

Oh I do inspect a few of the generated deals, mainly to check whether I have overlooked something and have to refine my specifications and because the deals in themselves are often interesting.

I do not use my own code but Dealmaster PRO and I found it to be reliable. The DD analyzer (DeepFinesse) is beyond doubt.

But all this is a completely different issue.

I think I can export generated deals out of Dealmaster PRO, but what do you want me to do with them?

Publish them all in BBO? Seems to me impractical to do. My sample size is usually 1000 deals, unless generating will take ages.

But why would we need to hide anything?

Best way to check results is for somebody else to repeat them with their own software and sometimes with the same or their own specifications.

Whenever I published results and others used similar specifications in their simulations they came to similar results.

But frankly I do not understand all this skepticism of their validity, as if people had any incentive of making false or careless claims.

Simulation results are sometimes surprising and refute "standard wisdom". That's why I like them. Others seem to hate them for that reason.

I wonder who has an open mind here.

 

Rainer Herrmann

[cherdano]

I am not aware that this particular issue has been researched specifically.

However millions of deals played have been researched and differentiated according to contract level and whether played in a suit or in notrump.

 

There were certainly plenty of 4-3 fits in partials when lower-level suit contracts were researched.

Double dummy makes very slightly less tricks (About 0.1 tricks at suit contracts below game level).

 

Rainer Herrmann

If the average of A and the average of B over the whole population are exactly the same, then that does not mean that the average of A and the average of B over a subset of the population is exactly the same.

[gnasher]

I think I can export generated deals out of Dealmaster PRO, but what do you want me to do with them?

Publish them all in BBO? Seems to me impractical to do. My sample size is usually 1000 deals, unless generating will take ages.

No, I'd expect you to produce a few examples. You say that you look at a few of the generated deals. Next time you do a simulation, why not share those deals as well as the conclusions?

 

But frankly I do not understand all this skepticism of their validity, as if people had any incentive of making false or careless claims.

You do know that this is the Internet, don't you?

 

Simulation results are sometimes surprising and refute "standard wisdom". That's why I like them. Others seem to hate them for that reason.

I wonder who has an open mind here.

I have an open mind, but I tend to be sceptical of assertions that aren't supported by either logic or evidence. I'm not saying that this applies to your simulations, but in this forum generally there is a culture of saying "I did a simulation. I'm not going to tell you how I did it, I'm not going to show you the actual hands, and I'm not going to offer any evidence that I know what I'm doing." That's not qualitatively different from telling us that sugar pills will cure cancer.

[rhm]

If the average of A and the average of B over the whole population are exactly the same, then that does not mean that the average of A and the average of B over a subset of the population is exactly the same.

True, so what?

 

Very likely DD simulation is way off on 4-3 fits and also way off on 5-3 fits but in opposite direction and the whole cancel each other miraculously out

I am not a missionary and I am not interested in convincing you to believe the earth is round if you want to believe the earth to be flat.

Continue dreaming if you like.

 

Rainer Herrmann

[cherdano]

I am actually quite open to the idea that garbage stayman should be used more often than it is.

But the idea that this is proven with the simulation data you linked to is laughable.

 

I have played a 4-3 fit or two in my life. And I know that (especially when our combined hands are fairly weak) I would really LOVE to know whether trumps split 3-3 or whether they split worse.

I also know that defending a 4-3 fit isn't easy, but it's much easier when you know it's a 4-3 fit from the beginning.

 

I would be happy to make a bet that double dummy results for declarer significantly outperform single dummy results in this situation (low-level partial, defense knows from the beginning that it's a 4-3 fit - say the auction was 1N-2C-2D-2H-2S).

I also know that defense again an unrevealing auction (1NT all pass) is harder than on average.

[fromageGB]

I agree with what Cherdano is saying. I don't place much faith in DD simulations because normally real life is nothing like DD. If there were single dummy simulations, then that is a different matter.

[Cthulhu D]

I agree with what Cherdano is saying. I don't place much faith in DD simulations because normally real life is nothing like DD. If there were single dummy simulations, then that is a different matter.

 

Is it? We always have hand records with deep finesse trick totals printed on them at the end of every club (team and pairs) game, and when we go through the results of a MP game against the deep finesse results most contracts come up the same, and of those that don't, 60-70%+ are the result of clear defensive errors.

 

The percentage of hands where deep finesse can roll it home taking some absurd line of play is very small.

 

If contract selection was being done by Deep Finesse that's a different question. It can often see that you want to be in some absurd 6C= in your 5-1 club fit rather than 4S+1 in your 9 card spade fit or whatever, but when you consider the strain selected by the room the results are usually pretty accurate.

[awm]

Is it? We always have hand records with deep finesse trick totals printed on them at the end of every club (team and pairs) game, and when we go through the results of a MP game against the deep finesse results most contracts come up the same, and of those that don't, 60-70%+ are the result of clear defensive errors.

 

The percentage of hands where deep finesse can roll it home taking some absurd line of play is very small.

 

This is often true in game and slam level contracts. I've found it to be much less so in partials. The various statistics seem to back that up. 1NT is a very difficult contract to defend, especially when declarer's hand is mostly unknown. Often the wrong opening lead can blow the contract, or the wrong very early switch. 4-3 major fits on fairly balanced hands are tough to play however; often you have to guess whether to draw trump early (which is usually right if the trumps divide 3-3 and disastrous if they don't).

[Siegmund]

I don't have any hard numbers on double-vs-single dummy for 4-3 partscore fits, specifically. That is true. Though it's not obvious to me that they should be wildly different, at least in a systematic way (in the case of NT vs suit comparions we are talking about here, it's the difference between two double-dummy results that matters, and it is likely that with a 3-3 break it is right to pull trumps in a suit AND right to peel the whole suit in NT while with a bad break it is right not to pull trumps AND right to retain a stopper in the suit in NT.)

 

I did inspect some number of the dealt hands, before running an automated script to deal out thousands of them. The most striking feature was that the hands where running to a suit made the most difference were the hands where responder was hopelessly weak and one suit was unprotected in notrump -- you don't get rich trying for 110 instead of 90, you get rich by conceding -100 instead of -400. Notrump on less than 20 HCP is often a huge disaster, while a 4-4 fit on less than 20 HCP is usually just fine and a 4-3 fit on less than 20 HCP is...well... not fun but often less painful by a couple tricks than 1NT would have been.

 

Anyone who is familiar with Deal 3.1 and cares to inspect the script is welcome to send me a PM.

 

The one way in which I consider this type of analysis most flawed has to do with the quality of the defense. I have done extensive sims of blind leads against 3NT and 4M reached by various auctions, and the less informative auctions consistently receive opening leads that blow a trick more often (to the tune of about 30% of the time vs. 2NT-3NT, 20% of the time vs 2NT-3C-3D-3NT, to 10% of the time vs 2NT-3C-3M-4M.) I have not done the same experiments on the impact of leads against partscores like we are talking about in this thread. If the effect is similar -- that the defense against 1NT is likely to be 0.2 tricks worse than against 1NT-2C-2H-Pass -- that does certainly swing some borderline cases against Stayman, but won't change 2C being right on a 3352 0-count.

[mikl_plkcc]

Currently, I use crawling Stayman to deal with all 4-4 major hands with less than 8 HCPs. My notrump opening, as already mentioned in another post, has the following criteria:

• Absolutely no voids or singletons
  
• No two doubletons
  
• No 5-card majors
  
• No good 5-card minors (such as AKJxx)
  

 

I currently play non-forcing Stayman, with 2♥ as crawling and 2♠ as invitational with 5 ♠s and 5 or 4 ♥s which can be passed with ♠ fit.

 

For weak 5-4 or 5-5 hands, I go through crawling Stayman;

for invitational 5-4 or 5-5 hands, I either bid Stayman or transfer to ♥, and then bid 2♠, which is non-forcing;

for game-forcing 5-4 hands, I use Smolen transfer;

for game-forcing 5-5 hands, I transfer to the higher than bid the lower at the 3-level.