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Zar points, useful or waste of energy New to the concept, does it help...

#141 User is offline   pbleighton 

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Posted 2005-August-29, 18:28

I'm not going to attempt to pass judgment on this system as a whole, but I agree with Richard about the 1NT opening. I can see that a good response scheme could bid games pretty accurately (I play a 10-13 NT so I'm not so concerned about the wider range), but I see two problems with part score contracts:

With unbalanced hands 1NT will often be a quite inferior contract. Perhaps the most distinguishing characteristic of the 1NT opening versus 1 of a suit is that you will actually play your opening bid a lot. If the response scheme usually takes you past 1NT with a weak responder, then you have big problems with the balanced hands which form the majority of the 1NT openers.

Bailing into 2M with a weak hand is also much dicier.

Peter
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#142 User is offline   Zar 

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Posted 2005-August-29, 21:50

>
This heated discussion inspired me to read part of the Zar book again
<

That was the point of the heat, Hennie :-) Hopefully some other people would follow your simple approach towards the truth :-)

>
(I've read older versions of the book in the past, but there's much more in it now). I think that it is a very interesting read, but you have to be very very careful in accepting the conclusions that Zar draws from his calculations.
<

I don’t really do any calculations, Hennie, Seriously. I just copy and paste from the computer output. If you think that I am drawing tables and typing in numbers in a calculator, you are putting much more faith in me than I deserve.

>
For instance, here is an interesting quote from the Zar book, page 117:

"So in favorable vulnerability your opponents' chances to have a succesful sacrifice against a game are a good 70%!"

This is a very dangerous quote that should not be taken seriously imo.
<

It was just a joke, Hennie– thus, it was not supposed to be taken seriously :-)

>
all of the following must be satisfied:

1) We are playing in our best strain.

2) We have exactly 10 tricks in this strain.

3) Our best sacrifice is at the 4 level.
<

You are right with 1) and 2). And that is actually what the study suggests.

On 3) though you can see the exact numbers for ANY kind of sacrifice.

And I am sure you understand that these 70% do NOT translate to the Nike’s slogan “Just Do It” - it simply means that if you have a fit yourself, you would have a good sac 7 out of 10 attempts (I wish you play against me in the other 3 :-)

Also, the 70% refers to the COMBINED probability, right – down 1, 2, or 3 in favorability.

Plus, this is kind of “insurance” for me, so if you come and say “Zar, I followed your Rule and failed”, I’ll be able to reply “Sorry, Hennie, you are in the 30% bracket :-) Ask the statistics experts, they’ll explain :-)

>
So basically, it is only a useful guide when they know that their best fit is spades and we are playing in their best fit, namely hearts.
<

I assume the second “their” is a typo. BUT the sac is not necessarily in hearts, right?

Sine you are going to be “overboard” anyway, the suit doesn’t really matter – the only thing that matters about the suit is if it is below or above their suit (aka, the level you’d need to go to).

>
Furthermore, they have to know that we can make 4H but not 5H. If they know all of this, surely they have a good idea already of how many tricks they can take in 4S.
<

I am not sure I am following you here, but there is a separate table that shows the exact numbers for any combination. This certainly does NOT mean that “they know that we can make 4 but not 5”. In this respect you can consider that the study for the sacrifices is made “after the fact” rather than being a guideline of what to do once they reach 5 Hearts – it can only help you if you don’t have other pointers and considerations from the bidding. Just like you would fines a missing Q against the hand which you have counted to have 4 cards instead of the 2 his partner has (in lack of any other indication for the position of the Q).

>
If you are a gullible reader then you might be better of not reading this book.
<

You make feel like I am trying to trick some innocent girls :-) And you are trying to protect them :-)

>
However, if you are willing to think carefully about what Zar says, then this book can give you plenty new information.
<

That indeed is the absolute goal, honestly. I am not trying to change your MOSCITO system and trick you into playing ELEPHANT or something ... just use your head, that’s all.

>
That's my book review based only on the section on the law of total tricks . I was never interested in the bidding system (sorry Zar)
<

Oh, I think I have to go to the bathroom ... :-)

>
so I didn't read that part. I'm very skeptical about the idea that good statistical ideas alone will lead to a good bidding system. I don't know anything about Zar the bridge player (so please take no offense), but I think that good bidding systems are made by good bridge players.
<

Actually, may I kindly ask to move the previous sentence here? Thanx :-)

>

1) Is the variety of hands really so much greater than in standard? For instance, opener can have 1, 2 or 3 cards in each major, while in standard you can have 2, 3, 4 or 5 cards, wider by 1 level. You might say that 5 is quite rare, but 1 is also quite rare for Zar. In a minor you have 2-5 cards as in standard, but there is only one possible distribution for 2 (3-3-5-2 for clubs), compared to 3 in standard. So the number of cards in each suit is better known at Zar-1NT than in standard.
<

Hennie, you told everybody that you didn’t read the system :-)

The exact distribution may be known at Level 2, if you read the answers to the Responder’s “Zar Stayman” of 2 Clubs.

However, the 1NT opening is geared towards NEGATIVE inference rather than towards direct manifestation of values. Actually, the entire system is geared towards negative inference. When you open 1S I know that you cannot have more than 5 cards in the suit (since you would have opened at Level 2 with 2D or at Level 3 with 3S), and if you have 4 cards, you cannot have a 6-4 with a side 6-dars suit (since again you would have opened 2D and on the transfer bid would have bit 2NT to show 6-4).

When you open 1NT I know that you do not have any 4-card Major. That’s the vital information here, rather than the fact that you can tell me your exact distribution on your next bid – that’s just an added bonus.

>
2) The 6-Zar point range is not much wider than the 3-HCP range. Remember that an ace or king gets more Zar points than HCP's, and Zar gives extra points for distributional values. I'd estimate that 6 Zar points is about the same size as the 14+-17 range often used by 2/1 players, if they evaluate their hands properly.
<

They never do evaluate their hands properly, Hennie :-)

I am not sure what 6 Zar Points you are talking about ... may be you have in mind 5 – that’s the range. To see EXACTLY what the ranges are and what probability, you can go to page 20. The probabilities for every HCP holding are given in the right-hand-side column.

Having said that, from COMPARISON view point, Zar Points are 2 times LIGHTER than the “normal” points (I’m tempted to say the “abnormal points” :-) Meaning that in Goren terms you need 26 points for a Game, while in Zar terms you need twice that amount (52). However, that 2:1 ratio may be very misleading as you very accurately pointed out.

Since you are talking about the 1NT opening, the MAX distributional point you might possibly have there is 13, leaving you with 13 for HCP+ CTRL or an expected minimum of 10 HCP! You have to face that (not you personally since you don’t give a demn about the system :-). The max HCP would be when the distributional points are minimum, that is 8 at 4333. Then at 30 Zar Points (the MAX for the 26-20 interval) you would have 22 from HCP and CTRL, so an expected MAX of 18 HCP. So theoretically you may hold anywhere between 10 and 18 HCP.

Did you manage to catch your eyeballs, Hennie :-)

>
3) If (1) and (2) don't hold then this should also not be a problem, right?
<

Not sure what you mean exactly, but I hope I addressed the issue – let me know if there is anything unclear.

Thanx, Hennie:

ZAR
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#143 User is offline   POJC 

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Posted 2005-August-30, 01:17

hrothgar, on Aug 30 2005, 12:48 AM, said:

Zar, on Aug 30 2005, 01:24 AM, said:

We can leave it right here though, if it is tough for you :-)

Maybe my problem is that I haven't been able to see this wonderous system in action...
If its as good as you say, I'm sure I'll rush right over to adopt it.

I'd be happy to arrange a match some time. I'll play MOSCITO with Free or The_Hog. You can this use this thing.

As I noted, I think the structure is badly flawed. I expect that you'll have large losses on your Pass/1/1/1N openings. You're gonna need to score amazingly well with the rest of your structure, especially given that those openings occur slightly more than 25% of the time... However, I've been wrong before. I might be wrong this time around.

I'm sorry but your criticism really points out that u haven't READ what Zar writes. Try that out for starters...

What Zar has done is somewhat similar to magic diamond (reversed) but has shown a different way to evaluate hands, based much more on distribution and controls instead of mostly HCP.
Eg we all know that a very good 14HCP plus a good 5 card minor is not hurt by opening as a 15-17 1NT. Most of the time it won't be a problem, more often than not we will get a better score. What Zar has done is set this into system and proposed a biding system around it.

But by now you must know a most of your criticism was one helluva backfire. The question is are you man enough to try to look into what ZAR really has done ?
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#144 User is offline   POJC 

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Posted 2005-August-30, 01:30

I have a question for Zar:
I don't understand the "preempts", in your proposed system.
Eg.
KQTxxxx
x
xx
xxx

That's around 22 ZAR so no 3 opening in Zar. This i would normally open 3 in favorable
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#145 User is offline   hrothgar 

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Posted 2005-August-30, 05:47

POJC, on Aug 30 2005, 10:17 AM, said:

What Zar has done is somewhat similar to magic diamond (reversed) but has shown a different way to evaluate hands, based much more on distribution and controls instead of mostly HCP.
Eg we all know that a very good 14HCP plus a good 5 card minor is not hurt by opening as a 15-17 1NT. Most of the time it won't be a problem, more often than not we will get a better score. What Zar has done is set this into system and proposed a biding system around it.

But by now you must know a most of your criticism was one helluva backfire. The question is are you man enough to try to look into what ZAR really has done ?

I hardly think that my criticism has "backfired" on me

Zar has placed two different items on the table:

The first is his "Zar Points" evaluation scheme. Tysen and I have critiqued this evaluation scheme since day one. In particular, Tysen has some rather telling statistics that suggest that Zar points aren't particularly accurate compared to a variety of alternative hand evaluation metrics.

Zar has now proposed a bidding system. This system has three main characteristics:

1. It uses Zar points as its hand evaluation mechanism
2. It uses both 1 and 1 are strong artifical and forcing openings
3. It uses bids from 1 <--> 3 to show a variety of "common" hand types

I've enjoyed playing a lot of weird stuff in my day. I genuinely LIKE weird systems. However, his strikes me as badly flawed.
Alderaan delenda est
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#146 User is offline   POJC 

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Posted 2005-August-30, 06:14

hrothgar, on Aug 30 2005, 01:47 PM, said:

I hardly think that my criticism has "backfired" on me

Zar has placed two different items on the table:

The first is his "Zar Points" evaluation scheme. Tysen and I have critiqued this evaluation scheme since day one. In particular, Tysen has some rather telling statistics that suggest that Zar points aren't particularly accurate compared to a variety of alternative hand evaluation metrics.

Zar has now proposed a bidding system. This system has three main characteristics:

1. It uses Zar points as its hand evaluation mechanism
2. It uses both 1 and 1 are strong artifical and forcing openings
3. It uses bids from 1 <--> 3 to show a variety of "common" hand types

I've enjoyed playing a lot of weird stuff in my day. I genuinely LIKE weird systems. However, his strikes me as badly flawed.

No backfire?
As in:
hrothgar: " you don't know anything about statistics"
Zar: "except for my Ph.d. in statistics" .........

There is no reason to go namecalling. You don't like Zar, fine he won't force it on you.

1. Yes. i try to do a few Zar point evaluations once in a while on interesting hands. Haven't had bad results yet. It's not weird it's just ONE way to do a SYSTEMATICAL evaluation.
2. Not weird, same principle as Magic Diamond. Does it work? I don't know.
3. See my above post, I agree that something is a bit strange here, maybe even flawed
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#147 User is offline   Free 

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Posted 2005-August-30, 06:45

I wonder why you waste your 2M bids on hands which VERY rarely come up: 5M, 6+m and constructive strength :) Is it to fill a whole or something?
"It may be rude to leave to go to the bathroom, but it's downright stupid to sit there and piss yourself" - blackshoe
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#148 User is offline   Zar 

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Posted 2005-August-30, 07:30

>
I can see that a good response scheme could bid games pretty accurately
<

If your PD has the balance of the power to drill towards Game, of course.

Then you will be happy that you have opened 1NT since in a sec he’ll know your exact distribution, and from there - your HCP + CTRL power (deducting the points that come from your exact distribution).

I suspect that we will be discussing the other case though :-)

>
(I play a 10-13 NT so I'm not so concerned about the wider range), but I see two problems with part score contracts. With unbalanced hands 1NT will often be a quite inferior contract. Perhaps the most distinguishing characteristic of the 1NT opening versus 1 of a suit is that you will actually play your opening bid a lot.
<

Very true, Peter.

The question is what happens after you open 1NT and your PD passes (see below the case when he doesn’t pass).

The worse case scenario is you go down 2 vulnarable undoubled – your opponents do not have a game and collect 200. Cannot help that – just swallow the pill IF your PD has passed (correctly, of course).

If they double, then you bid your 5-card-suit if you have one (5332 or 5431), and simply pass with 4432 and 4333 (the 4-cards again can NOT be in any Major by definition – that’s why it is also much easier to maneuver after double since he knows that your 4-card suits are the minors). Your pd manipulates adequately, knowing your distribution. Note that you may use the rdbl as a reflection bid too.

Now, you realize that as a response to the 1NT opening, ONLY the 2C “Zar Stayman” response is forcing – even 2D from your PD is to play.

As Mike Rosenberg said once “the important thing is your PD to know what you open with”.

>
If the response scheme usually takes you past 1NT with a weak responder, then you have big problems with the balanced hands which form the majority of the 1NT openers. Bailing into 2M with a weak hand is also much dicier.
<

Weak responder can get you past 1NT only with his own playing suit as discussed above. His only forcing is 2C.

Hope that addresses the question – as I mentioned in the reply to Hennie, 1NT is geared towards negative inference (regarding the Majors) and towards pre-emptive effect (barring the 1H and 1S opening from the opponents at a moment when you don’t have any Major yourself).

Cheers:

ZAR
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#149 User is offline   inquiry 

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Posted 2005-August-30, 10:57

For those of you struggling with the ZAR bidding system (I don't mean learning it, I mean trying to figure out why it is designed as it is), I think the answer is simplier than you might suspect.

Zar has determined to his satisifaction that counting ZAR points is a good start to any hand evaluation, but that you need to also calculate ZAR FIT and ZAR MISFIT points. To do the Misfit point thingee, you need a good idea of your partners distribution. Then you can easily apply his metric, and the correct level falls out the other end (sometimes with a reality check for missing ACES).

Until you appreciate the ZAR MISFIT calculations he proposes (and which I find very interesting), trying to appreciate or understand the reason for his choices in his bidding system is, well, confusing to say the least. But once you "grok" (am I showing my age?) the basic principle on which the system is built, it begins to make a lot of sense. Is it really playable? I don't know. Haven't tried it. But at least I can answer the questions most of you ask.. and if you think about his evaluation method, most you will be able too.
--Ben--

#150 User is offline   han 

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Posted 2005-August-30, 12:41

Zar,

I'm not sure why you respond with "I have to go to the bathroom now" (twice in your reaction to some of my comments that were intended seriously), or with "This is getting grotesque now, I'll stop here" (half a dozen times in response to Richard's post). I thought that Richard's point (opening 2M with 5-6 distribution and 5 levels of Zar-points is quite restrictive) was interesting and I would enjoy seeing a better answer. You did give a reason for these openings in a later post (to make sure that 1M is exactly a 4-card suit I believe), but this does not counter the argument that 2M is made with a very low frequency.

Let me respond to a couple more of your reactions to my post:

"Hennie, you told everybody that you didn’t read the system :-)"

I didn't read the whole system, but I'm always eager to respond to any topic I think I understand. I don't know the numbers as well as you do, but I think my response was basically the same as yours.

"Did you manage to catch your eyeballs, Hennie :-)"

Not sure what you mean by that expression, I'm not a native English speaker. I think I catch my eyeballs on anything related to bridge (hoping I used the expression in a correct manner).

"I don’t really do any calculations, Hennie, Seriously. I just copy and paste from the computer output. If you think that I am drawing tables and typing in numbers in a calculator, you are putting much more faith in me than I deserve."

Ouch, did I make such a naive impression that you had to write this??? I sure hope that this was another one of your jokes.

BTW, my name is Hannie, or actually Han. Think that makes us even when it comes to typos :)
Please note: I am interested in boring, bog standard, 2/1.

- hrothgar
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#151 User is offline   han 

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Posted 2005-August-30, 12:57

inquiry, on Aug 30 2005, 11:57 AM, said:

For those of you struggling with the ZAR bidding system (I don't mean learning it, I mean trying to figure out why it is designed as it is), I think the answer is simplier than you might suspect.

Zar has determined to his satisifaction that counting ZAR points is a good start to any hand evaluation, but that you need to also calculate ZAR FIT and ZAR MISFIT points. To do the Misfit point thingee, you need a good idea of your partners distribution. Then you can easily apply his metric, and the correct level falls out the other end (sometimes with a reality check for missing ACES).

Until you appreciate the ZAR MISFIT calculations he proposes (and which I find very interesting), trying to appreciate or understand the reason for his choices in his bidding system is, well, confusing to say the least. But once you "grok" (am I showing my age?) the basic principle on which the system is built, it begins to make a lot of sense. Is it really playable? I don't know. Haven't tried it. But at least I can answer the questions most of you ask.. and if you think about his evaluation method, most you will be able too.

This part I got Ben. But I still think that good bidding systems will be made by people with a lot of high level bridge experience (and these experiences should lead to the basis of their system). I can't imagine that you disagree with this.

I've seen many books about bridge systems that tell you how to evaluate hands for the system. I don't like that, I will evaluate hands the way I want to, thank you very much, and then use the system if I like it. Now Zar has much interesting stuff to tell about hand evaluation. But then he also tells us to play which system to play with it!

I know this is not fair to Zar, he has made it very clear that he also considers hand evaluation and bidding system two completely seperate issues, and that we don't need to play his system to gain from the book.
Please note: I am interested in boring, bog standard, 2/1.

- hrothgar
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#152 User is offline   Double ! 

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Posted 2005-August-30, 13:16

inquiry, on Aug 30 2005, 11:57 AM, said:

But once you "grok" (am I showing my age?) the basic principle on which the system is built, it begins to make a lot of sense.

If my memory serves me well, I thought that to "grok" meant literally "to share water". Perhaps there is another definition. Am "I" showing MY age.

ps: someone in my family has a zillion Sci-Fi books and magazines.
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Posted 2005-August-30, 13:41

Hannie, on Aug 30 2005, 02:57 PM, said:

I know this is not fair to Zar, he has made it very clear that he also considers hand evaluation and bidding system two completely seperate issues, and that we don't need to play his system to gain from the book.

I have not "warmed up" to his system yet either. It is not that I don't think there is method in his "madness", there actually is. And it is not because I think his evalaution method is wrong, I think it is actually very very good (here tysen2 and richard will disagree with me probably). But it is a lot like the LOTT, it is not always right and you have to know how (or when) to apply adjustment. His MISFIT points give a big help in this way, I liked ZAR points before, I really, really like them now. The reason why I am not excited about his bidding system (backbone actually) is ecause I like (despite the complications I have added to my version) natural bidding.

Now, ZAR will tell you his is natural but I think I play as well as or better than the majority of the field, so I like starting off on the same footing as the field (five card major, normalish NT). I also prefer five card majors to four card ones. Yes, yes, I know it is perhaps an unfair view. But I have played both and I like five card better. Now, Zar's 1H and 1S opening bids are closer to weak 1NT openings (stregnth wise) than anything else. So maybe some of what I don't like about four card majors but with relativley unlimited stregnth will go away with his system. I don;t thiink I will like it, but eventually, I will try it out. As Roland says, I am a system freak, if I don't play it, I can't decide what works and doesn't work. Who knows, I may even steal an idea from it to fix some problem or the other I view in what I play.

What I do like about ZAR, is his evaluaiton criteria gives me extra things to think about when I am bidding my hands. I start imagining my partners distribuiion and calculating Zar fit or misfit points, I start adding huge numbers on misfit hands with a superFIT suit, and I start subtracting huge numbers on misfit hands without super fits... and you know what, I like the general result. Do I go strickly by the numbers? Nope, but it helps me focus and try to make an educated guess rather than a simple guess.

But I think the real focus should be on the evaluation method. No one has experience with the system to make useful comments, imho.
--Ben--

#154 User is offline   Zar 

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Posted 2005-August-30, 13:52

>
I have a question for Zar. I don't understand the "preempts", in your proposed system.
<

I don’t either, to be honest, POJC :-) I just read my book – didn’t find any :-) However, please read below for the real answer to your IMPORTANT question.

>
♠ KQTxxxx
♥ x
♦ xx
♣ xxx

That's around 22 ZAR so no 3♠ opening in Zar. This i would normally open 3♠ in favorable
<

This topic is discussed WITH the corresponding numbers in the book so you can make you OWN choice looking at these numbers. IF you decide to stick with your “normal” opening of 3S above, you can CERTAINLY do so – you just have to push the opening (meaning 26 ZP+) with any 6+ cards into the opening of 2S (or 2H correspondingly) – this also addresses the question of Free. You are absolutely free to do so AND to modify/add anything you decide. That’s why it is NOT called Zar Points Bidding System, but Biding BACKBONE – there are almost no conventions even, if you have noticed.

The point is the balance between a bid where your PD knows that he can RELY on 26 ZP and 7-card suit (thus being able to IMEDIATELY take the appropriate intelligent action) vs. opening 3S pre-emptive with all kinds of hands, lengths, and holdings (which again is just fine if that’s your choice – and your PD knows about it :-). Opening with 26 ZP and 7-card suit is just geared towards the most important thing in the Backbone – limit yourself early and use negative inference.

When your opening is 4-Levels wide and the suit-lengths are between 2 and 13, almost the only “negative” inference your pd can make is “OK – my PD opened, so he doesn’t have less than ... 13 cards – otherwise he would have called the Director”.

“Would-have” is the key to negative inference, right? I believe it is important to enable your pd to think on INFORMATION rather than just letting him scratch his head staring at the back of your cards fully concentrated in an effort to “see-through” and make an “expert judgment” :-).

Do you have a point in the importance of pre-empts though? Absolutely! And it’s up to you and your PD to decide what best fits your style and priorities.

>
I wonder why you waste your 2M bids on hands which VERY rarely come up: 5M, 6+m and constructive strength. Is it to fill a whole or something?
<
Free, please read the answer to POJC above - hope that helps.

>
Tysen and I have critiqued this evaluation scheme since day one. In particular, Tysen has some rather telling statistics that suggest that Zar points aren't particularly accurate compared to a variety of alternative hand evaluation metrics.
<

The “variety of alternative hand evaluations” has been put to a match of 105,000 boards. A total of 9 methods, including 2 flavors of LTC – the Classic and the Modern style. I know you are a writer, not a reader, but try to download the results and have a look – just glimps over, rather than “wasting your time” in detailed reading and thinking :-)

105,000 boards of Part-scores, Games, Slams, and GRANDS is a LOT – you have nowhere to hide behind “critiqued this evaluation since day one” (you obviously were quick to critique at “day one” back then also, as you admit – don’t know why that rush).

And you will see what is and isn’t “particularly accurate” (to use your “scientific statistical” term).

Is it OK to keep using LTC instead of reading about something else? Absolutely! You can keep counting HCP only if that’s what constitutes bridge-fun for you. Different people enjoy different things.

ZAR
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#155 User is offline   Al_U_Card 

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Posted 2005-August-30, 14:29

Double !, on Aug 30 2005, 02:16 PM, said:

inquiry, on Aug 30 2005, 11:57 AM, said:

But once you "grok" (am I showing my age?) the basic principle on which the system is built, it begins to make a lot of sense.

If my memory serves me well, I thought that to "grok" meant literally "to share water". Perhaps there is another definition. Am "I" showing MY age.

ps: someone in my family has a zillion Sci-Fi books and magazines.

"Grok" from the "Stranger in a strange land" Sci-Fi book by Robert Heinlein. Mostly used to replace adolescent fantasies about what transcendescent ecstacy you would experience from GROping and ***King but maybe that's just my twisted point of view. (It has been 40 yrs or so since I read the book.)
The Grand Design, reflected in the face of Chaos...it's a fluke!
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#156 User is offline   awm 

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Posted 2005-August-30, 14:56

There's a lot of different stuff on the ZAR website. The simulation results on different types of hand evaluation are actually pretty convincing. This seems like a fairly straightforward thing to figure out -- supposing that we make game (or slam) decisions primarily on the basis of some evaluation method (i.e. high card points + distribution, losing trick count, ZAR) how often will we get it right? He's careful to measure from both sides (both good games missed, and bad games overbid to). It's a fairly clear case that ZAR is better than any comparably "simple" evaluation system out there.

My own hand evaluation is based on several things -- primarily a combination of high card points and losing trick count, with some influence from suit quality and controls. Comparing my own evaluations (based upon years of playing experience) to ZAR points, there is remarkable similarity in the results. I doubt this is a coincidence, and for someone without extensive experience staring at hands, ZAR points are a great way to go about evaluation. I don't expect to see a flood of expert players (many of whom have played hundreds of thousands of hands) switching to ZAR. But for someone in the intermediate/advanced range hoping to improve it's a great idea.

Now as to the bidding system, I think some things may have been ignored. On many competitive hands, it is essential to evaluate the degree of fit early in the auction. This is actually more important than figuring out the combined level. It's often the case that you can figure out that you want to bid 4 on a hand, without actually knowing whether the contract will make or be a good sacrifice. This is where the ZAR bidding system seems to have a lot of holes. Artificial bids like the 1 and 1 calls tend to make it hard to find the best fit right away. Four card majors are also weak in this regard. The tight limits on the ZAR strength of opener's hand help you figure out what you can make, but in competitive auctions the goal is the par spot, not necessarily the making spot. I'd argue that precision style openings (accurate to within two levels) are sufficiently precise in terms of playing strength to reach a good spot in most constructive auctions.

This is also the reasoning behind the preemptive openings that ZAR bidding seems to ignore. How can partner know whether to raise to game if I open 3 on a wide range of hands? In general he cannot know whether game will make. But whether bidding 4 is right, is not necessarily the same thing as whether 4 will make! As long as partner frequently makes the right decision, it doesn't really matter how often we are making the contract (if we go down, the decision will often be right if opponents were making 4, or were talked out of a making 5-minor).
Adam W. Meyerson
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#157 User is offline   Zar 

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Posted 2005-August-30, 21:54

>
Zar,
<

Hi. Hannie (apologies for misspelling your name in the previous post – just an innocent typo really- forgive me).

>
I'm not sure why you respond with "I have to go to the bathroom now"
<

It was just a quote from Beavis and Buthead, Han (easier than Hannie). It says “Oh, I think I have to go to the bathroom”. It’s a common quote in the software circles (you may guess why :-) Nothing worth the space we devoted already to.

>
(twice in your reaction to some of my comments that were intended seriously), or with "This is getting grotesque now, I'll stop here" (half a dozen times in response to Richard's post).
<

Your counting is good! I did say that once :-)

Points was I just don’t’ want to get involved in personal “pseudo-attacks” for nothing, when I hoped we could discuss more interesting stuff (I think). Don’t you?

>
I thought that Richard's point (opening 2M with 5-6 distribution and 5 levels of Zar-points is quite restrictive) was interesting and I would enjoy seeing a better answer.
<

It was Free’s question and I did address it with the answer to POJC. I don’t know what you mean by “5 levels of Zar Points” – really. The 2M openings should not be considered “isolated” but part of the entire length-related structure. It’s not like you scratch your head and start thing “well, what should I put here ... why not 5-7 two-suiters both headed by a K? Sounds exotic enough ...”. Rather, it covers its “portion” of the “negative-inference” structure of the bids. As with the openings at level 3, you are free to make your own modification (like dropping the 7-card suits down a level) but you should take in consideration what happens with the OVERALL structure of lengths that you want to maintain clear for your partner and enable him to do the negative inference.

>
You did give a reason for these openings in a later post (to make sure that 1M is exactly a 4-card suit I believe), but this does not counter the argument that 2M is made with a very low frequency.
<

Please let me know if the above short addition is not enough.

>
Let me respond to a couple more of your reactions to my post:

"Hennie, you told everybody that you didn’t read the system :-)"

I didn't read the whole system, but I'm always eager to respond to any topic I think I understand.
<

You are taking all this jokes very seriously. OF COURSE you should be eager to respond – these are free discussions HOPEFULLY for the benefit of the Game in general, and to improve our skills in one or another direction.

>
I don't know the numbers as well as you do, but I think my response was basically the same as yours.
<

Don’t quite get that, but again – please take it easy and ask ANY question or express ANY opinion you want, that’s why it is called “Discussion Forum”. I personally don’t think it is a good place for personal attacks especially ones based on “air”, but it looks like even that’s OK here, so ...

>
"Did you manage to catch your eyeballs, Hennie :-)"

Not sure what you mean by that expression,
<

Han, that’s just my style.

I meant that you probably are VERY SURPRISED by the length of the interval. I just write what naturally comes to my mind, translating to English from Bulgarian on the fly :-)

>
I'm not a native English speaker.
<

That just makes two of us :-) Seriously!

I don’t know how to talk anymore ... :-) You knocked me off my feet :-)

>
I think I catch my eyeballs on anything related to bridge (hoping I used the expression in a correct manner).
<

I am afraid you didn’t actually – as silly as it might sound from the mouth of another ESL guy like me (ESL is English as a Second Language, nothing offending). Unlike you tough, I have some confidence in my grasp of the English Language (among other things :-)

This does NOT matter though - the important thing is that YES, you are obviously a serious player and please feel free to ask any question at any time. There is nothing wrong in being an ESL person like you and me.

That’s what the Discussion forum is about – exchange of ideas, questions, and opinions.

Ben, did I explain the BBO policy well here or am I stepping on someone’s toes (yours or Fred’s obviously).

I enjoy reading your posts and questions and have never had anything “behind” my jokes - that’s just my style.

>
"I don’t really do any calculations, Hennie, Seriously. I just copy and paste from the computer output. If you think that I am drawing tables and typing in numbers in a calculator, you are putting much more faith in me than I deserve."

Ouch, did I make such a naive impression that you had to write this??? I sure hope that this was another one of your jokes.
<

I guess you have deleted the word “dumb” in front of the word “jokes” from your initial response :-) I give you a personal card-banche to take anything that offends you in any shape or form as a joke. Never meant to hurt you in any possible way.

>
BTW, my name is Hannie, or actually Han. Think that makes us even when it comes to typos
<

It does :-)

Please let me know if you have any question on any Zar Points related matter – I’ll try to answer it the best way I can (I think I am qualified to do that).

Cheers:

ZAR
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#158 User is offline   Echognome 

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Posted 2005-August-31, 01:03

I find this all to be a bit strange of a discussion. I understand that Zar wants to sell his (her?) book, but it makes the discussions rather fruitless when the responses to legitimate questions are basically "read my book for the answer."

I also believe that we have two separate issues here: the Zar hand evaluation method and the Zar bidding "backbone" as it was called. In terms of hand evaluation, I thought Adam's comment on it being a useful tool for beginner/intermediate players was interesting and also Ben's point about Zar fitting points and misfit points. Now, one thing when I read Lawrence's book on hand evaluation was that it considered all kinds of auctions, mostly competitive ones. Forgetting for the moment about having a fit or not with partner, we also need to take into account honour location in light of opponent's bidding. The nice thing about the hand evaluation books I have read is that they have focused on being "system free." That is to say, learning hand evaluation should help me to become a better bridge player regardless of the system I choose. I believe that Ben does just this with Zar points and that's great. It certainly seems like a reasonable starting point when little else is known about other hands.

In terms of the Zar bidding system, from what I have seen discussed on this forum, I have my doubts about it as well. However, I'm a believer that preempts work, so any system that limits the amount of preempts I can make I will not likely be fond of. Before anyone answers with saying that the limited openers allow for more light openings, I can only say "so does my system!" The only ways we can make any comparisons are theoretically or empirically. If you read through Marston's notes on Moscito you will see plenty of theoretical foundations. Empirically, I don't believe the exercise should be to compare automata, but rather how the system does when good players are playing against other good players. Note that precision and moscito are played at the highest levels. Now, I'm not expecting that any new system will be instantly adopted, but if Zar thinks his system is worthwhile then why not take up Richard's challenge and choose a couple of players to play against he and teammates online? A good long team match would make for interesting viewing and a good comparison of the systems. Note it would also be a good advertisement for the system if it does well.
"Half the people you know are below average." - Steven Wright
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#159 User is offline   awm 

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Posted 2005-August-31, 01:30

The notion of aiming for the "par spot" instead of the "making spot" actually has a lot of repurcussions for hand evaluation and system design. To give an example:



On these two hands 4 is excellent. You will lose one trick in each suit except spades, unless the breaks are extraordinarily vile. Every hand evaluation method worth its salt will tell you to bid game:

LTC: 7 losers (ok 6 if you adjust for aces) opposite 7 losers (still 7 adjusted) = 14 (13) for game
LOTT: 10 trumps each way --> 20 total tricks, so contract for 10 tricks
ZAR: 28 opposite 25 = 53, more than enough for game
Even goren points: 20 total hcp, plus 5 (shortage), plus 2 (trumps beyond 8) = 27

So great, what's the problem? The problem is, suppose we change the ace of clubs to the king. Now game looks a little iffier according to ZAR and goren. But if the club king isn't scoring, then the opponents can make 4 (lose one spade and two diamonds). So you should definitely bid 4 even though it may go one set.

Now change the ace of clubs to the deuce. There's not really any play for 4 now, you will lose two clubs and one trick in each red suit. But the opponents are frigid for 4. So you should STILL bid 4, it is STILL the par spot. ZAR will tell you 4 is a bad game on only 47 ZAR points -- and correctly so! But when designing a bidding system (and selecting a contract in a serious field) you absolutely must be able to compete to 4 on all of these hands.

The key point here is that the distribution of the hands will determine the par spot almost regardless of the actual values. This is something ZAR (and the bidding backbone) don't seem to take into account. It might be interesting to try designing a hand evaluation method around the par spot instead of the making spot. I expect that when you hold the vast majority of the hcp strength these spots are often the same -- but just because you hold 52 or so ZAR doesn't mean the opponents can't hold the same. Taking the hand above with the club ace changed to the king (so your side holds 51 ZAR) the opponents hands may be:



Total ZAR points for E/W: 32+20 = 52.
Adam W. Meyerson
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#160 User is offline   mike777 

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Posted 2005-August-31, 02:53

The key point here is that the distribution of the hands will determine the par spot almost regardless of the actual values. This is something ZAR (and the bidding backbone) don't seem to take into account. It might be interesting to try designing a hand evaluation method around the par spot instead of the making spot. I expect that when you hold the vast majority of the hcp strength these spots are often the same -- but just because you hold 52 or so ZAR doesn't mean the opponents can't hold the same. Taking the hand above with the club ace changed to the king (so your side holds 51 ZAR) the opponents hands may be:


What does Par mean?

Is is the best theortical result?
Is it best practical result?
Is the the best Actual result?

The definition of Par is not clear and not obvious in this usage.

In any case Zar , I keep hearing Zar uses normal distributions? Is this valid assumption? If it is fine, if Zar in fact assumes something else fine. For those of those that think t-or p values are something that our kids use in T- ball help please.
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