big spade fit

[Finch]

No sarcasm intended in this question, are you trying to argue that straight ace ask hands are more common than keycard hands after 1M p, or are you just saying it as an interesting side note?

 

It was an interesting side note. Both hand types are (IMO) so rare that I have no useful frequency analysis.

Hands where opener wants to keycard at his second bid are not so uncommon, but hands that want to keycard directly in response to a 1M opener are very seldom seen. Particularly if you disagree with doing it on a hand like this.

[VM1973]

I know that Zar points overvalue controls because in NT 4321 is very close to reality and the most common game in bridge is 3NT. This is the third time I wrote this down, this is why I said Zar points overvalue controls. Let me write this down a fourth time: Zar points overvalue controls because controls are not as valuable in NT as in suit contracts and you do not know when you open 1♠ that you will play 4♠.

As I asked before, can you link me to something supporting your position? I guess the answer is no. So I link you to http://groups.google.com/group/rec.games.bridge/msg/0fe90fb84687c5e9

 

According to this link the average error rating of systems are:

HCPs: 1.23

Bergen: 1.08

HCPs plus 3-2-1 distribution: 1.07

ZP: 1.05

BUM RAP +321: 1.03

Binky Points: 0.99

 

Accordingly I conclude that the simple 4-3-2-1 system is bad, ZPs are superior and Evolved Binky Points may be the best of all, though I'm not sure yet as I still haven't found a coherent description of how the system works.

[gwnn]

Like I said, helene_t made a logistic regression analysis some time before, but I guess you skipped through that part of my post. This is for suit contracts: http://www.bridgebase.com/forums/topic/32125-hand-evaluation-for-suit-contracts-investigated/

 

and this is the post on 3NT: http://www.bridgebase.com/forums/topic/9893-tests-for-a-double-dummy-solver/page__view__findpost__p__94283

 

but VM, this is all slightly futile. Bridge will never be completely scientific, and no evaluation method will ever be very accurate. And what I conclude about your approach to the game from labelling AKxxx Axx xx xxx 1.5 kings above minimum is that you're willing, or striving, to suspend all your judgement in favour of the Zar point results. Similarly with accepting Axxxx Axxx x xxx without a problem. Your judgement in bridge is an asset, not a cancer. You will always run into problems where you need your judgement, for example if you sohuld double them or bid on or pass, etc.

 

Anyway, since when are you interested in scientific formulae for the game, I thought every hand was different and inductive reasoning was faulty?

Edited August 23, 2011 by gwnn

[Zelandakh]

gwnn, go easy! :) Most bridge players who are interested in innovative stuff go through phases where they think they have found the new way. Whether it be Zar points, forcing pass systems, combine carding, whatever. This is a natural part of the development for this type of bridge player. I am sure VM will move on after a while to develop other aspects of his game. In the meantime the lessons he learns with ZP will probably be beneficial, if for no other reason than seeing that yes, distribution is very important, but not the be all and end all that ZP would suggest. But nonetheless much more than simple 3/2/1 with a fit.

 

ZP are fairly close to 4.5 - 3 - 1.5 - 1 adjusted Milton with 5 - 3 - 1 for distribution. Hence they work extremely well when there is a fit. Unfortunately, when we have to play in NT they stop working. In most bidding systems it is easier to add unexpected extras than to suddenly say you have less than before. This is the inherent advantage of the above-mentioned adjusted Milton approach over ZP. You reach the same evaluation but you do it without overvaluing the misfits. You also do not reduce your credibility by saying that AKxxx Axx xx xxx is 1.5 kings above minimum. Perhaps it is close when partner has a good major suit fit, when they do not you need to re-evaluate.

 

While doing the re-evaluation think a little about what gwnn said VM. The point made here is extremely good. Use ZP by all means, always making sure to analyse the pros and cons later against alternative evaluation strategies so as to see the strengths and weaknesses of each. But above all work on your bridge judgement. This will pay dividends back to you irrespective of which evaluation system you eventually use. Listening closely to what some of the most experienced posters on BBF say can help but mostly this will come from experience. You cannot always rely on an evaluation system or generic rule for such decisions!

[VM1973]

Like I said, helene_t made a logistic regression analysis some time before, but I guess you skipped through that part of my post. This is for suit contracts: http://www.bridgebase.com/forums/topic/32125-hand-evaluation-for-suit-contracts-investigated/

 

and this is the post on 3NT: http://www.bridgebase.com/forums/topic/9893-tests-for-a-double-dummy-solver/page__view__findpost__p__94283

 

but VM, this is all slightly futile. Bridge will never be completely scientific, and no evaluation method will ever be very accurate. And what I conclude about your approach to the game from labelling AKxxx Axx xx xxx 1.5 kings above minimum is that you're willing, or striving, to suspend all your judgement in favour of the Zar point results. Similarly with accepting Axxxx Axxx x xxx without a problem. Your judgement in bridge is an asset, not a cancer. You will always run into problems where you need your judgement, for example if you sohuld double them or bid on or pass, etc.

 

Anyway, since when are you interested in scientific formulae for the game, I thought every hand was different and inductive reasoning was faulty?

You're right that bridge will never be scientific and considering that science is empirical and inductive that is a good thing. If you understood much about scientific philosophy, you'd realize that what I propose is falsificationism, which is an invention of Karl Popper in which theories are advanced and attempts are made to falsify them. As such, this method is logically consistent and avoids all the problems that plague induction.

 

First let me propose that we examine these two hands:

 

♠Kx

♥Kxx

♦Kxx

♣AJ10xx

 

♠QJxxxx

♥xx

♦AJ10x

♣Qx

 

Let us suppose that due to an auction best forgotten South is declaring 4♠ and the defense starts with three hearts, the 3rd ruffed. East wins the ♠A and returns a spade and you're left to make the rest of the tricks. How do you proceed? The percentage play for picking up the rest of the tricks is to cash ♦AK catering for the possibility that the ♦Q will drop and fall back on the club finesse. HOWEVER if you are using double dummy declarer play the declarer will magically know the right way to finesse against ♦Q. Needless to say this is patently unfair.

 

Now this doesn't mean that such evaluations are completely useless - rather that you must be careful how you apply them. I don't personally think that you can look at such a database and say "A 10 should be worth 0.4" because 10s are worth a lot more when you can look at your opponents' hands and know if you should hook the 10. Accordingly an 0.4 would be the maximum amount a 10 would be worth and its real value would be lower.

 

Additionally, let's look at this perfect hand:

 

♠AKQJ

♥AKQ

♦AKQ

♣AKQ

 

37 HCPs = 13 tricks so a trick is, on average, 2.846 HCPs. Even if we generously assume that 10s are worth 0.4 points that still means you need more than 7 tens to make a one trick difference... and there are only four 10s in the pack.

 

I also couldn't help noticing that the post said: "Interestingly, queens got a weight of 0.8 rather than the traditional 1.0...." In what system do queens traditionally have a weight of 1.0? Is he really implying that a queen is worth only twice as much as a ten? Or did he misspeak and mean the Jack? And if that's true, why did he continue, "It could be argued that DD-simulation understimates the values of queens because declarer often has to guess how to catch the queen: Kings can only be finesed in one way (except for sec Kings, throw-ins etc)."

[gwnn]

Yes I suppose she meant 1.6 instead of 2. I am not sure, but she is around, she can tell us.

 

Looking at AKQJ AKQ AKQ AKQ will not give you an accurate picture of how many HCPs are worth how many tricks. For example, it would mean that you need 28.5 hcp's for 10 tricks, a conclusions that nobody accepts. The reason why AKQJ AKQ AKQ AKQ gives you a false picture is twofold: first of all it is a hand that offers you certainty for 13 tricks, second of all because in real contracts you often take tricks with jacks, tens, or even twos, because of length.

 

I know about the pitfalls of double dummy evaluations, you do not need to give an example hand to tell me about it. However, you cannot dismiss such investigations altogether. Declarer plays much better when he sees all four hands, but defenders also make much better opening leads. There have been other investigations (sorry, no links) that came to the conclusion that double dummy results give better results than reality for declarer at grand and small slam level and worse results at smaller contracts, and that somewhere around the 3NT/4M level double dummy results actually come pretty close to reality. I will not look for this link, it is somewhere here on the forums, I think it was a bridge browser study. I suppose you can disregard this as my anecdotal non-evidence, but at least answer me this: how is it that Helene's numbers give much higher importance to controls in suit contracts and the coefficients are actually very close to 4321 for no trump? How can you explain that purely on double dummy errors? Surely if you want to talk only about double dummy errors favouring declarer, they favour declarer in NT and suit contracts as well?

 

Anyway, it is funny that you link to Tysen's investigations, where Zars perform only slightly better than HCP+321 and in his own words

 

I'm surprised at Zar's poor performance.

 

Surely you don't mean that people who use HCP's never think about their shortnesses? That we, the obsolete HCP addicts will reject invitations after, say

 

1♠-1NT

2♥-3♥

 

with all 11 counts, whether 5422 or 6430?

Edited August 23, 2011 by gwnn

[mikeh]

You're right that bridge will never be scientific and considering that science is empirical and inductive that is a good thing. If you understood much about scientific philosophy, you'd realize that what I propose is falsificationism, which is an invention of Karl Popper in which theories are advanced and attempts are made to falsify them. As such, this method is logically consistent and avoids all the problems that plague induction.

 

VM: why do you write as if the person you are addressing is ignorant of such ideas as falsification? Which, as you presumably know, is merely one aspect of the scientific method and, as such, predates Popper by more than a few years.

 

You may be as intelligent as you seem to want us to believe, but the empirical evidence is so far not supportive of that notion.

 

There is a fundamental difference between ignorance and stupidity. So it may be that ignorance is to blame for such faux pas as posting that, when holding AKQxxxx, partner will hold 3+ support more than 60% of the time, but that post did raise some eyebrows.

 

Ignorance is nothing to be embarrassed about. 99.999999% of the world population lacks the knowledge to be classed as an expert bridge player, and most of them don't care ;)

 

More importantly, ignorance can be cured, by the simple task of learning. However, assumptions of superior intellect and disdain for those who already possess such knowledge is likely to impede and possibly prevent your progress.

 

So, while I am not trying to stop you from posting.....engaging in robust discussion of the ideas that are new and appealing to you is a great way to learn....I am suggesting that you approach the forums as if those posting in response to you are (1) your intellectual equals , and (2) where warranted, possessed of greater knowledge than you.

 

That doesn't mean that they are 'right'. There are a number of highly skilled, highly accomplished players who post here and arguments amongst them are common. Which is, of course, one reason the game is so appealing to most of us who are hooked on it.

[gwnn]

Mikeh so you believe that there are about 0.7 bridge experts alive today? :)

[mikeh]

Mikeh so you believe that there are about 0.7 bridge experts alive today? :)

Unless I am seriously in error, and typed a 9 (or 99) too many, I think I suggested about 70....and that is an error....I'd go with 700. Of course, if we self-rated as on BBO, I'd have to extrapolate to 700,000.

 

Anyway, if I were VM, I'd make some caustic reference to your obvious failure to understand hyperbole, invoking a factoid picked up from wikipedia :D

[VM1973]

Yes I suppose she meant 1.6 instead of 2. I am not sure, but she is around, she can tell us.

 

Looking at AKQJ AKQ AKQ AKQ will not give you an accurate picture of how many HCPs are worth how many tricks. For example, it would mean that you need 28.5 hcp's for 10 tricks, a conclusions that nobody accepts. The reason why AKQJ AKQ AKQ AKQ gives you a false picture is twofold: first of all it is a hand that offers you certainty for 13 tricks, second of all because in real contracts you often take tricks with jacks, tens, or even twos, because of length.

 

I know about the pitfalls of double dummy evaluations, you do not need to give an example hand to tell me about it. However, you cannot dismiss such investigations altogether. Declarer plays much better when he sees all four hands, but defenders also make much better opening leads. There have been other investigations (sorry, no links) that came to the conclusion that double dummy results give better results than reality for declarer at grand and small slam level and worse results at smaller contracts, and that somewhere around the 3NT/4M level double dummy results actually come pretty close to reality. I will not look for this link, it is somewhere here on the forums, I think it was a bridge browser study. I suppose you can disregard this as my anecdotal non-evidence, but at least answer me this: how is it that Helene's numbers give much higher importance to controls in suit contracts and the coefficients are actually very close to 4321 for no trump? How can you explain that purely on double dummy errors? Surely if you want to talk only about double dummy errors favouring declarer, they favour declarer in NT and suit contracts as well?

 

Anyway, it is funny that you link to Tysen's investigations, where Zars perform only slightly better than HCP+321 and in his own words

 

 

 

Surely you don't mean that people who use HCP's never think about their shortnesses? That we, the obsolete HCP addicts will reject invitations after, say

 

1♠-1NT

2♥-3♥

 

with all 11 counts, whether 5422 or 6430?

I had assumed we were speaking about NT contracts. Suddenly now I find reference to shapes 5-4-2-2 and 6-4-3-0. Do you often bid NT with those while counting your 0.4 for tens? Somehow I doubt it.

 

As for Tysen's investigations, I refer you to http://www.bridgebase.com/forums/topic/2542-zar-points-useful-or-waste-of-energy/page__p__17560#entry17560 in which it was suggested that ZPs misevaluate 5-3-3-2 and 5-4-2-2 hands, among others. I've already written to ask for more information but in any event the solution could be quite simple, for example:

Subtract 1 point for 5-3-3-2, 6-3-2-2, 5-4-2-2, and add 1 point for 4-4-4-1. Surely this will improve the performance of ZPs if tysen's research is correct.

 

As for the idea that 2.846 points per trick is off, somehow I think that's unlikely as using those figures results in 25.6 HCPs for 9 tricks in 3NT, which is not far off from the people who figure 25 or 26 points. In case you've lost my train of thought, I should mention that I'm simply talking about NT, not 6-4-3-0 shapes.

 

And yes, to answer your question, I do think that those who use 4-3-2-1 to evaluate their hands for strictly no trump purposes do not include points for shortness.

[VM1973]

VM: why do you write as if the person you are addressing is ignorant of such ideas as falsification? Which, as you presumably know, is merely one aspect of the scientific method and, as such, predates Popper by more than a few years.

 

You may be as intelligent as you seem to want us to believe, but the empirical evidence is so far not supportive of that notion.

 

There is a fundamental difference between ignorance and stupidity. So it may be that ignorance is to blame for such faux pas as posting that, when holding AKQxxxx, partner will hold 3+ support more than 60% of the time, but that post did raise some eyebrows.

 

Ignorance is nothing to be embarrassed about. 99.999999% of the world population lacks the knowledge to be classed as an expert bridge player, and most of them don't care ;)

 

More importantly, ignorance can be cured, by the simple task of learning. However, assumptions of superior intellect and disdain for those who already possess such knowledge is likely to impede and possibly prevent your progress.

 

So, while I am not trying to stop you from posting.....engaging in robust discussion of the ideas that are new and appealing to you is a great way to learn....I am suggesting that you approach the forums as if those posting in response to you are (1) your intellectual equals , and (2) where warranted, possessed of greater knowledge than you.

 

That doesn't mean that they are 'right'. There are a number of highly skilled, highly accomplished players who post here and arguments amongst them are common. Which is, of course, one reason the game is so appealing to most of us who are hooked on it.

I don't see why throwing in an extra few words to set someone off in the right direction if they decide to Google what I've said is somehow insulting.

 

As for the scientific method, it's based on a logical fallacy and nothing can be demonstrated empirically because it runs into an infinite regress problem. So the existence or lack of empirical evidence is completely irrelevant and frankly I'm surprised that you would mention it... unless you simply meant to be insulting and didn't have the stones to say it straight out.

[Zelandakh]

And yes, to answer your question, I do think that those who use 4-3-2-1 to evaluate their hands for strictly no trump purposes do not include points for shortness.

This is true. Most add points for length instead. A 5 card suit is typically worth about 0.5 hcp in isolation, hence players often bump 5332 hands up to the next range category when at the top of their NT range unless there are compensating negatives.

[gwnn]

VM1973, before we go any further, I forgot to ask about Tysen's methods, I think he used GIB results from all sorts of contracts, and not just 3NT, or am I mistaken?

[Bbradley62]

unless you simply meant to be insulting and didn't have the stones to say it straight out.

I think he pretty much said it straight-out.

[mikeh]

I don't see why throwing in an extra few words to set someone off in the right direction if they decide to Google what I've said is somehow insulting.

 

As for the scientific method, it's based on a logical fallacy and nothing can be demonstrated empirically because it runs into an infinite regress problem. So the existence or lack of empirical evidence is completely irrelevant and frankly I'm surprised that you would mention it... unless you simply meant to be insulting and didn't have the stones to say it straight out.

This is degenerating into exactly the sort of exchange that led me to stop posting for several months. Since it is apparent that you can't even understand my earlier posts, I will stop now before I say something I would only come to regret.

 

Meanwhile I leave you to explore the fascinating world of calculating the precise arithmetical value of any given hand.

 

Once you've mastered that, you can consider moving on to learning how to play bridge :D

[gwnn]

It is true that I was slightly confused on what you meant by 2.846 hcp/trick, I thought you meant in any contract but you meant NT, but I will not apologise for that, because your train of thought was completely obscure. You replied to a post of mine which had two links: one to the NT analysis and one to the suit contract analysis and you started with an example on 4♠. How should I know that the rest of your post will be about no trumps? Where did you write that? Please try to make clear what you mean next time.

 

So my point still stands: HCP troglodytes do indeed look at their shortnesses, and their controls when they have decisions and it looks like they will play in a suit (i.e. they found a fit). They change their evaluation according to the way the bidding evolves. ZAR fans have a tendency to overbid with controls because a significant proportion of the time they will not play in suit contracts, but rather no trumps.

 

You gave one link, which I think compares results of all methods in all contracts. Unless you can show me a survey which differentiates between no trumps and suit contracts, your link is not especially helpful. I at least provided you with something, and Helene's surveys point to the conclusion that 6421 is roughly good for suit contracts and 4321 is roughly good for NT. Note that Helene also made some research on how much a shortness should be worth, etc. I did not want to complicate matters by mentioning that.

Edited August 23, 2011 by gwnn

[aguahombre]

Anyway, if I were VM, I'd make some caustic reference to your obvious failure to understand hyperbole, invoking a factoid picked up from wikipedia :D

Probably. But, certainly you and the rest of us just thought it was cute.

[tysen2k]

As for Tysen's investigations

 

[snip]

 

I've already written to ask for more information

So VM emailed me to bring me into this discussion...

 

Unfortunately I don't have much to contribute besides what I posted about 6 years ago. I haven't really looked at it since. Searching for my name and zar points should bring up a lot of stuff.

 

And as I've said several times before, I think the interesting stuff on hand evaluation isn't on who has the most accurate system down to the last decimal point. What's interesting is quantifying how your evaluation changes as the bidding progresses (the auction in the OP is a perfect example). Other interesting stuff that I always wanted to look into are things like how high cards and distribution really aren't additive and how the relative importance between strength and distribution changes depending on how balanced partner is (and the opponents). I feel there's a lot of potential here for someone to research, but I just don't have the time.

 

Tysen

[Zelandakh]

This is degenerating into exactly the sort of exchange that led me to stop posting for several months.

 

I think there is a distinct danger that threads like this will put other posters off too. Disagreements are normal, if they were not then we would not have much to talk about would we? But comments like "you didn't have the stones" and "you can consider moving on to learning how to play bridge" are not constructive and imho should not have a place on these boards.

[Yu18772]

Is there a way to delete your own reply on someones post?

[aguahombre]

Is there a way to delete your own reply on someones post?

yes. Edit out what you posted via delete key; then just make a brief statement that you deleted it. Doesn't work when someone has already quoted you, unless they edit out their quote also.

[cloa513]

This thread is way off track. The original question is one of what to bid with hand with moderate slam potential and low strength whether it be the example hand or

♠Axxx ♥Kxxx ♣Kxx♦Kx over an opening bid 1♠ and other possibles. Opener needs moderate slam potential (two aces at least) to continue and considerable strength in this example. A suggestion is 3NT, opener rebidding 4♣ with 2 aces allowing further asks for strength , 4♦ with 2 aces and a king outside of trumps, 4♥ 2 aces and king of trumps, 4♠ sign off.

[VM1973]

VM1973, before we go any further, I forgot to ask about Tysen's methods, I think he used GIB results from all sorts of contracts, and not just 3NT, or am I mistaken?

I'm not certain. As I said, I've written a letter and I'm still looking forward to a response. Temporarily I'm just deducting a point for the shapes he says are badly evaluated and adding a point for 4-4-4-1 and seeing how I feel about it.