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Zar points for opening bids terrible evaluation method

#1 Guest_Jlall_*

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Posted 2004-October-25, 21:07

The zar craze has caused me to look a little into the opening bid evaluation method. The method basically overlooks the most crucial aspect of initial hand evaluation: honor location. Also, it pays no attention to spots, or rebid problems. It pays too much importance to controls and short suits which only become really important ONCE A FIT IS ESTABLISHED. Initially, these are not as big as zar points makes them into. Lets look at a few hands:

A
KJxx
Jxx
Jxxxx

26 zar points, an opening bid (!!). Are you serious? weak suit, rebid problem, stranded jacks, no spots. Nobody in their right minds would open this

KQT98
AJT9
xxx
x

Also 26 zar points. Quite different hands???

-
x
Kxxxxxx
Kxxxx

27 zar points, a clear opening bid. Are you kidding? Your hand isnt worth much UNTIL YOU HIT A FIT. One cannot seriously open this hand.

QJT
KT9
QJT
KQJx

25 zar points. Not an opening bid. A spot rich, albeit aceless hand. I wouldnt be ashamed to open this ONE NOTRUMP, let alone pass?

--
Axxx
Axxx
xxxxx

26 zar points. opening bid. Let alone the rebid problems, the weak suit, and the lack of texture.

OK perhaps im giving some hands that dont come up much. How about a few balanced 10-12 counts.

QTx
QJ9x
AT8x
Kx

25 Zar points. Not an opener. A 12 count with working honors and good supporting spot cards, and 2 four card suits. hard to see how this could not be opened.

AK
Kxx
Jxx
xxxxx

26 zars, an opener. forget the terrible suit, and the short suit honors and stranded jack.


Count me out of zar points please, thanks.
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#2 User is offline   HeartA 

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Posted 2004-October-25, 22:11

JL, I am with you. Zar points make sense only after fitting is found.
Senshu
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#3 User is offline   jikl 

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Posted 2004-October-26, 00:40

What I tell people I am teaching when choosing to make an opening bid has little to do with points...

What is the worst bid you can hear from partner? And then, do you have a comfortable rebid?

Seems to work well with intermediates and below.

Sean
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#4 User is offline   Gerben47 

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Posted 2004-October-26, 02:34

Good post Justin!
Zar points just don't work. We all know that more distribution equals more potential and that aces are undervalued. Zar points try to put this in numbers but there are many aspects it does not recognize as Justin pointed out.

Also I think that some people open hands with few HCP with Zar points as an excuse that should not be opened, mostly this means hands with 8-9 HCP and much distribution. In my opinion hands under 10 HCP should either be passed or opened with some preempt.

If you have a misfit then partner will drive to game with 13 HCP and you will be in 3NT with a combined 22-count and a misfit. Oh joy.
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#5 User is offline   joker_gib 

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Posted 2004-October-26, 02:59

I'm also with Gerben and Justin (very good examples !!) !

Zar can only be used to re-evaluate the hand after a fit is found :wub:

Alain
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#6 User is offline   whereagles 

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Posted 2004-October-26, 03:08

Honor location is NOT the most crucial point of opening bids. That would be shape and hcp count. Also, over-evaluating two-suiters is statistically justified: if I recall correctly, about 75% of all 5-4 shapes have a fit somewhere. A whooping 85% for a 5-5, and like 95% chance of fit for a 6-5.
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#7 User is offline   EricK 

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Posted 2004-October-26, 03:09

Gerben47, on Oct 26 2004, 08:34 AM, said:

Good post Justin!
Zar points just don't work. We all know that more distribution equals more potential and that aces are undervalued. Zar points try to put this in numbers but there are many aspects it does not recognize as Justin pointed out.

Also I think that some people open hands with few HCP with Zar points as an excuse that should not be opened, mostly this means hands with 8-9 HCP and much distribution. In my opinion hands under 10 HCP should either be passed or opened with some preempt.

If you have a misfit then partner will drive to game with 13 HCP and you will be in 3NT with a combined 22-count and a misfit. Oh joy.

This last point is the key.

You can't play Zar points (or similar) and keep the normal responding basis as if opener weren't playing Zar points. The fact that that doesn't work is not surprising, but also not a point which should be held against Zar points!

If partner makes adjustments to his misfitting 13 points then he will realise that it is not a GF opposite a minimum Zar opener and not bid game! Zar says that all 26 point hands (and so on) are of the same strength as each other opposite random hands for partner. That does not mean of course that they have the same chance of being totally useless opposite certain hands for partner, or that they will be as easy as each other to bid in your system.

His method of calculating the strength of the hand is totally separate from his advice to open all 26 point hands.

Personally, I think Tysen's point count (which can be found on these message boards somewhere) is a better scheme. It tends to agree with Zar on run-of-the-mill hands but is more accurate on balanced hands or hands with singleton honours, isolated quacks and so on.

FWIW, the hands in the original post are valued at 16, 19, 20, 21, 18, 18, 16 which I think is pretty close to the relative playing strengths of the various hands.

Eric
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Posted 2004-October-26, 05:08

I've never been convinced about ZAR points anyway. It gets you in slams on finesses (one or more), but it might help you to find sharp games imo. However, it's not worth the energy if you know how to evaluate your hand good enough...
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#9 User is offline   Chamaco 

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Posted 2004-October-26, 05:10

jlall said:

QJT
KT9
QJT
KQJx

25 zar points. Not an opening bid. A spot rich, albeit aceless hand. I wouldnt be ashamed to open this ONE NOTRUMP, let alone pass?


This hand is terrible.
Opening it a 15-17 NT is really bad.
4333 and no aces it is worth a 12-14 NT not more, despite the tens and the 9.
Amd, after opening it either a weak NT or 1C, I would pass throughout if pard does not force me to bid.
Much better to defend.

Ok, the above comments of mine were given BEFORE checking the Kaplan-Rubens evaluator (http://www.gg.caltec...u/~jeff/knr.cgi)
The k&R evalkuator rates the hand 13.75 hcp




Quote

QTx
QJ9x
AT8x
Kx

25 Zar points. Not an opener. A 12 count with working honors and good supporting spot cards, and 2 four card suits. hard to see how this could not be opened.


This is also a pretty bad hand, and opening it depends on your standards.
Even many people who do not play Roth-Stone, will pass that kind of hand, because it is worth less than 12 balanced.
It lacks controls.
I'd much rather open xx-Axxx-Kxxx-Axx, e.g. an 11 count with good controls rather than this.
The point is, controls matter more than intermediates.


In any case, this is a borderline hand, which I'd open, but considering it a stretch; i'd open only for the "in quick-out quick" principle.
And if pard goes down, I'd apologize to him for my overbid.

I wrote the above without checking K&R evaluator, now let's see how it rates the hand: 11.3 hcp


All in all, such balanced hands are evaluated in a similar manner by K&R and ZAR points.

As fare as the rest of the post is concerned, I agree that misfit hands are overvalued by ZAR.
It's up to you to use the right tools for hand evaluation at the right moment: even if you use Goren points to evaluate a 6-5 hand, you won't have much success.
Or if you use the Losing trick count or the law of total tricks for notrump contracts.

I think of ZAR as a tools very useful for distributional hands: you may hit a misfit and get a disaster, true.
So what ? Almost any freak hand is at risk of losing something, often large swings: going for a number in a doubled contract can be as high a risk as missing a slam that you would have found using ZAR or LTC.
The fact that ZAR suggests pushy actions with a 6-5 and 2 Kings is not in contrast with other much more accepted theories such as the LOTT or the LTC.
Of course it requires a calibration by pard because ZAR openers do not promise any defensive strength, so doubling opponents will need extra defensive strength by responder. But nothing comes for free.

Truth is that we like to remember only the disasters (or potential disasters) that support the theories we are fond of ... :wub:
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#10 Guest_Jlall_*

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Posted 2004-October-26, 06:01

QJT
KT9
QJT
KQJx

i can see a case for downgrading this hand from a 1N opener, but you definitely downgrade the potential of these spot cards. consider partner having a few normal hands

Kxxx
Axxx
Kxxx
xx

Because of the spots game is excellent, despite the misfit and the 2 balanced hands. If you downgrade this to a weak NT you will not find game.

Axx
QJxx
Kxxx
xx

Game is still good, a spade lead MIGHT set, but its worth the risk. Again you'll miss game if you downgrade.

Kxx
Qxx
A9xxx
xx

once again we will find game, and again its iffy on a spade lead, but its still not bad.

These are normal hands, and i dont think its worth the risk of missing game to not open 1N. Certainly the trick taking potential is massively increased by the spots (change the spot cards to low cards in these 3 examples and you'll see my point)

you claim that xx Axxx Kxxx Axx is a better hand than QTx QJ9x AT8x Kx. I think this is a gross misevaluation that is prevalent in ZAR thinking. WHEN OPENING THE BIDDING, controls are not as important...yet. Say you later discover that partner has 5 hearts. No i will definitely prefer the first hand. But that doesnt mean you cant reevaluate when that information comes to light. If you end in some contract like 1N or 3N, the second hand is a much better hand. Consider the following examples (where you dont have a major suit fit and land in 3N)

Axx
KTx
QJx
QJxx

on a spade lead (your partnerships combined shortes suit) youre going to have very little play for 3N opposite the first hand. The second hand yeilds very good play (again the spots play a major role). All of your prime values didnt mean much when partner bid a normal 3N on a normal 4333 13 count.
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#11 User is offline   Chamaco 

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Posted 2004-October-26, 06:27

Quote

i can see a case for downgrading this hand from a 1N opener, but you definitely downgrade the potential of these spot cards. consider partner having a few normal hands

Kxxx
Axxx
Kxxx
xx


In this case it is your partner that should reevaluate his hand.
His hand is a nice 10 count with good controls.
Controls matter much more than spot cards.

Partner will invite to game, and opener will accept the invitation, just like ANY 14 count would.


Quote

Axx
QJxx
Kxxx
xx

Game is still good, a spade lead MIGHT set, but its worth the risk. Again you'll miss game if you downgrade.


Same here: responder invites with a good 10 count with no wasted quacks, opener accepts as before.

I do not see any problem with these 2 hands.
Note that in both cases, using ZAR points responder's hand is well evaluated here as invitational hand (22-25 ZAR).

Quote

Kxx
Qxx
A9xxx
xx

once again we will find game, and again its iffy on a spade lead, but its still not bad.


Here too, this hand is a 9 countwith a 5 carder.
Using ZAR, it amounts to 9 hcp + 3 controls + 8 length points + 3 points (long suit- short suit ) = 23 = invitational hand.
This may be a stretch, but, just as you mentioned, here game IS a stretch, so it is fair.

THE POINT IS THAT IF YOU KNOW HOW TO DOWNGRADE THE HAND, YOUR PARD MUST KNOW HOW TO REEVALUATE HIS HAND, BASED ON SHAPE AND CONTROLS.
The first 2 responder hands you posted are nice invitational hands, not NORMAL hands, responder must know how to deal with them. The 3rd (BTW evaluated as invitational by ZAR) is borderline, but so is the chance for game (and the spade lead is far from unlikely, regardless of what you open).

Quote

you claim that xx Axxx Kxxx Axx is a better hand than QTx QJ9x AT8x Kx. I think this is a gross misevaluation that is prevalent in ZAR thinking.


The value of controls is something that has been acceopted since a long time, it certainly is not a singular feature of ZAR evaluation.
For example, the Kaplan-Rubens evaluation system rates the following hands as:

QTx QJ9x AT8x Kx = 11.30
xx Axxx Kxxx Axx = 12.00

So, if the primary importance of controls is a gross distortion (which I do not believe it is), it is not peculiar to ZAR, but it is common to many other systems of evaluation.

The point is that Aces are worth more than 4 hcp, and Q and J s are worth less than 2 and 1.
This concept is well known from much before ZAR.

Quote

Say you later discover that partner has 5 hearts. No i will definitely prefer the first hand. But that doesnt mean you cant reevaluate when that information comes to light. If you end in some contract like 1N or 3N, the second hand is a much better hand.


Sure.
It is absolutely obvious that the hands have to be reevaluated during bidding.
And good players know that Queen and Jacks (and even tens) are the honor-types which are more prone to be reevaluated when fitting with partner's suit.
It is well described in the Jeff Rubens article on "In and Out" principle of hand evaluation.

This concept is certainly not under discussion: but it applies to whichever system of hand evaluation you will use.
Even ZAR evaluation systems reevaluates the hand based on the fitting / misfitting honors.

So the final examples you mention are not conflicting with the view I am expressing :-)
These hands have no evidence neither against nor in favour of ZAR points (or whichever hand evaluation system), nor dealing with the deeavluation/reevaluatio issues I discussed previously.
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#12 Guest_Jlall_*

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Posted 2004-October-26, 06:42

partner will invite game opposite a zar opener with those hands???? *GASPS*. you are very full of contradictions now...lets see:

you open with:
xx Axxx Kxxx Axx

and invite with:

Kxxx
Kxx
Axxx
xx

HMM... you are VERY high, arent you?

Kxx
Qxx
A9xxx
xx

again, you seem very high! you are in 2N with both of these hands? Now this is just silly. You say you will invite with 9 counts with 5 card suits, and balanced 10 counts opposite a weak NT? in case partner has a perfecta FIFTEEN count? and game is terrible if partners 15 includes no spots. Partner will accept your invite with QJx Kxx QJx KQJx surely, and will be very surprised to go down. As for getting to 2N vul down several undertricks with your balanced 11 opp 9 and 10, that is just silly, and yet that is what you'd get to playing with yourself, by your own words. Inviting with these hands when you go down opposite most 14s and some fifteens (!!) should be a wakeup call. As for the debate about teh 15 point given in my example, the point is moot because ZAR downgrades it to a PASS. Not even worthy of a weak NT. Now, which is a better hand

QJT
KT9
QJT
KQJx

or

xx
Axxx
Kxxx
Axx?

the latter IS an opener in zar
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#13 User is offline   Acesfull 

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Posted 2004-October-26, 06:50

In terms of opening balanced hands, I believe the person who invented Zar points advocates not using them in those situations.

From http://public.aci.on...NeverMiss.html:


KQx
KQxx
QJx
Qxx

Quote

Would East open the bidding to begin with? The answer is yes, because he has more than 12 HCP and it’s an opening hand by any system. If the HCP power warrants an opening by itself, you open the bidding the way you usually do with the system you are using – most people would open 1 NT with the East hand. NOTE, that counting Zar Points with a balanced hand will NOT help you – with these 15 HCP you collect only 25 Zar Points which “formally” means you should pass.



Zar Points are geared towards aggressive bidding with distributional power rather than hands with brute HCP force and balanced hands


As for your other points, I have to agree.
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#14 Guest_Jlall_*

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Posted 2004-October-26, 06:58

thx acesfull, i didnt know that. Zar is so bad when it comes to evaluating unbalanced hands that i think it is even better (less worse) in evaluating balanced hands. lol.
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#15 User is offline   Chamaco 

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Posted 2004-October-26, 07:01

Quote

you open with:
xx Axxx Kxxx Axx

and invite with:

Kxxx
Kxx
Axxx
xx

HMM... you are VERY high, arent you?


I disagree.
These combined hands have a much better play that most 22-23 combined counts lacking aces.

However, depending on which system of bidding you use, you have the chance for a safe retreat in 3 diamonds, which is a fair contract after all
(e.g. if you play a form of checkback, a sample auction may go):
1D:1S
1NT:2C (invitational)
2H:3D

Even the second sample hand you posted will play better in 3 diamonds than 2NT and there is a way to get there.

Quote

You say you will invite with 9 counts with 5 card suits, and balanced 10 counts opposite a weak NT? in case partner has a perfecta FIFTEEN count?


The point is to stop thinking of points (sorry for the joke :) ).

But rather consider the overall quality of the hand.
Controls are of utmost imposrtance, and points as Q and J often are of no value at all (untile they are reevaluated).

Shape is also of more importance than a 2 pouint count difference if those hcp are Q or Js.

inviting with a 4432 10 count ? Yes, if the 10 count is Ace and Kings, because Aces are worth more than 4 hcp.
Yes, even opposite a 12-14 NT.

Inviting with a 9 hcp 5332 ?
This is stretching the limit, and I wrote it before.
I wrote that it is a borderline action, and that it depends on many issues (most important, fitting or misfitting honors).
Yet, even in that case, you have a safe retreat to 3 diamonds.

Quote

QJT
KT9
QJT
KQJx

or

xx
Axxx
Kxxx
Axx?

the latter IS an opener in zar


If you read carefully my post, I wrote that one should use the right tool at the right moment.
i am not a ZAR "adorator", blindly using it every time.

I think the two hands are of a much more similar playing strength than the hcp diufference expresses.
The first is more defense oriented and is worth about a max for a weak NT (about 14). It will accept any invitation by responder.
The second has a higher ODR ratio and is worth a miniumu weak NT (about 12). It will pass any invitation by pard.

I would open them both, despite what ZAR says of the first.
So what ?
I use the right tools in the situations where I think they work, I do not care about the war of religions between a system and another.

the point of my post is that ZAR is not such a novelty nor so crazy: it incorporates well known traditional concepts such the importance of controls and the Losing Trick Count.
Some times it works, some time it does not.
It is just another tool to be used under the right circumstances: try using a shovel to mix your tea, and you won't have much success :-)
"Bridge is like dance: technique's important but what really matters is not to step on partner's feet !"
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#16 Guest_Jlall_*

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Posted 2004-October-26, 07:17

You are right 3D will play well (you have a fit) which is the only reason the controls are now worth their upgrade. In NT you have no tricks. You will nevertheless be in 2N with

xx Axxx Kxx Axxx opp Kxxx Kxx Axxx xx

and go down a few most likely

you simply cannot invite on hands that go down in game opposite most maximums and go down many opposite minimums in 2N
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#17 User is offline   Chamaco 

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Posted 2004-October-26, 07:33

Jlall, on Oct 26 2004, 01:17 PM, said:

you simply cannot invite on hands that go down in game opposite most maximums and go down many opposite minimums in 2N

sometimes you go down, it happens even for some 28 hcp games.

But on balance, you'll find out that opening 11 counts made of AK only (and nothing wasted) and inviting with 10 count made of AK only (and nothing wasted) tends to payoff. (DISCLAIMER- do not provide 4333 hands please :) )

Remember, most of the time you won't have the overlapping of the 2 most minimum hands you posted, worst case scenario, admittedly possible, but not the percentage scenario.
Most of the time you'll have:
- a "normal" opener opposite a good 10 count made of AK , which makes 2NT (min opener) or 3NT (max opener) more often than not, OR
- an 11 count opener made of AK opposite opposite a "classical" GF or invitational hand, which also makes quite often.

You'll bid many games that have play in a combined 24 count, sometimes you'll go down, sometimes game will be cold, and sometimes you will make thanks to your magnificent dummy play technique :D
You'll also put moire pressure on opponents which will need to defend very accurately to avoid sllipping.
And the increased frequency makes it such that defenders tend to slip here and there or on opening lead (ask the Meckwell... ;-).

Furthermore, we have the added bonus everytime we discover a fit after inviting. (e.g. typical example, checkback after 1x:1y:1NT)
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#18 Guest_Jlall_*

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Posted 2004-October-26, 08:03

ah the old "sometimes you go down" argument. The question is how often will you go down?

Kxxx Kxx xx Axxx

1D p 1S p 1N p ?

now lets see what happens when you invite

Jx Axx AJxxx Kxx: parttner will surely go, a nice 13 with a 5 card suit (and aces and kings). this hand has almost no play for game.

Axx xx AKxxx Qxx: another very nice 13, terrible game.

Qxx Axxx AQJx Jx: 14 points, certainly a maximum. Very poor game.

do you really want to be inviting with this hand? will it really usually payoff?
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#19 User is offline   hrothgar 

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Posted 2004-October-26, 08:05

Jlall, on Oct 26 2004, 04:17 PM, said:

You are right 3D will play well (you have a fit) which is the only reason the controls are now worth their upgrade. In NT you have no tricks. You will nevertheless be in 2N with

xx Axxx Kxx Axxx opp Kxxx Kxx Axxx xx

and go down a few most likely

you simply cannot invite on hands that go down in game opposite most maximums and go down many opposite minimums in 2N

From my perspective, most of the discussion regarding Zar points has been overly simplistic. Ideally, this discussion should be decompossed into three separate threads:

Thread 1: Are Zar points an "accurate" system of defining hand strength? Sadly, Zar was never willing to provide a robust statistical analysis.

Thread 2: If Zar points are, indeed, and accurate hand evaluation technique, what strength is necessary for a constructive opening?

Thread 3: What type of response structure needs best complements the opening bids.

Needless to say, some recursion is desirable between these three threads.

Justin accurately points out that you can't blindly graft highly aggressive, highly distributional openings onto a traditional response structure without severely compromising the integrity of the system.
Alderaan delenda est
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#20 Guest_Jlall_*

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Posted 2004-October-26, 08:08

heh, my original post does not and will not address issue 3. However I do not think Zar points evaluates an initial hand's value well enough because it overlooks some crucial things and weights others wrongly. As such issue 2 is nullified
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