[tysen2k]

I agree that Binky points are not meant to be used at the table, and I say so much in my articles. In my point of view they do some good in a number of ways.

• Computer bridge programs can use them for more accurate evaluations
  
• It allows us to quantify what changes occur during the bidding. We all have judgement on how valuations change during the bidding, but it's nice to be able to quantify it.
  
• We may be able to derive other "simpler" formulas from these that capture most of the accuracy but don't require a calculator. This is the project I'm currently working on.

[Flame]

tysen2k, on Mar 26 2004, 12:41 PM, said:

5332 – Zar gives this 11 distribution points, or 3 more than a 4333 pattern. Therefore Zar says it should take 0.6 tricks more than 4333, when in reality it only takes 0.339 more tricks.

6322 – Similar story. Zar says it’s 1 trick better than 4333 when it’s only 0.660 tricks better.

5422 – Zar says 0.8 tricks when it’s 0.595

4441 – This time Zar undervalues the holding. Zar says it’s 0.6 tricks better when it’s really 0.810.

you say that 4441 is better then 6322, this seems wrong till you consider that the 4441 will worth more when i got my p suit support but then i will have additional zar points too.
my point is that the 4441 only become good when supporting p and then u get more zar points for it, while the 6322 is better before p have something to say.
That might or might not be true but that my "feeling" about it which reflects well with zar points.

[GijsH]

JonnyB, on Mar 18 2004, 03:08 AM, said:

Talking about hand evaluation......Iread a book a couple of years ago, by Laurence Drabble. Unfortunately, cant remember the title, but it dealt with a different way to evaluate combined hand strength - "Complete Hand Evaluation" he called it.
Has anyone heard of this..it seems to be totaly unknown here in NZ, but is possibly the most consistently accurate way to judge hand stength, that I have ever come across.
The second half of the book dealt with his bidding system.. "MidMac" if I recall. Well worth a read, if you can find a copy!

His name is Jon Drabble and the book is "A new approach to bidding", it is still for sale at book sellers like Amazon. I played MIDMAC several years, with good results, but like every system: two good players do better with it than two beginning players.

[Zar]

Hi all:

Thanx for the "heated" discussions - just noticed this discussion list, never been here before. And since I am Zar himself, I decided that I may be able to shed a light on any questions or confusions you might have. Would be glad to.

A quick remark - I noticed somewhere that you count 3+ Zar Points for any SIDE suit of a length of 4+. That's incorrect - you count "superfit" points of 3 per card above a fit of 8, regardless if that's a trump or a side suit.

Also, this is the simplified fit-version, rather than the "Zar Ruffing Power" calculations, which assigns 3 points for a super-fit card (above 8) if you have a side void, 2 points if you have a side singleton, and 1 point per super-trump if you only have a side doubleton. With 4333 your additional trump gets no points at all.

The simplified Zar Points that you know are programmed into the Zar Pid Mashine which you will find at the home-page (everything related to Zar Points, the Machine
including, is free as you probably know).

A last short note - comparing the Zar Points you know about (the simplified version) with Computer Bidding methods is comparing apples and oranges. I would be glad to run any comparison with the full version of Zar Points System (never published anywhere), which includes the Ruffing Power, the Footprints, sophisticated relays etc. which the average bridge player neither is interested in, nor would pay any attention to anyway.

Zar Points with the 3-points fit adjustment are just an easy-to-remember and easy-to-use at the table Hand Evaluation system, tested on millions of boards, while the research itself involves tens of millions indeed. I intend to publish the bidding system itself, but I am still working on it. In the mean time simply try the Bid Machine at

http://public.aci.on.ca/~zpetkov/

You simply use the SLIDERS to adjust the HCP, Controls, and Shape of the 2 hands and the Bid Machine bids in Goren, Bergen, and Zar (simplified Zar Points with 3-points superfits).

The Contracts may look strange (like 3.75 H or 6.40 NT) but the goal is to let you play with the sliders and see WHAT is the effect of having 1 more control for example, or what is the effect of slightly shifting the Shape etc. I hope you'll find it interesting and illuminating. Have fun.

ZAR

P.S. You may find the seven articles on Zar Points in the Japan Bridge Bulletins (Eric Kokish editor) at

http://bridge.cplaza...fest04/nec.html

Each short one-page article addresses different issues regarding Zar Points. Also an article will appear in tye next issue of The Bridge World.

Make it a great day:

ZAR

[inquiry]

Dear Zar Petkov,

Welcome to the Bridge Base Online Forum. We obviously welcome your input on this and other topics. I must say, I have been testing your hand evaluation methoid against a fair number of tough hands, and it is holding up very nicely. As the initiator of this thread I haven't formed a final decision yet on rahter I am gong to use it every day or not, but I have decided, for me, the answer to the question of useful or waste of energy seems clear, it is useful.

On the other hand, it does take a while to get use to all the counting.

Welcome again.

Ben

[mishovnbg]

Spoiler

---------------------------------------------

Hi Zar!

Spoiler

-------

Welcome to forum! Will be nice if you join to our discussiond here too! You can explain for example you realy bidding ideas in thread about unnatural systems for example...
Will you be so nice to add sveral typical examples of Zar counting with detailed explanation?

Spoiler

----------------------------------------------------------------

Misho

[Zar]

*** Ben wrote:
>
I have been testing your hand evaluation methoid against a fair number of tough hands, and it is holding up very nicely. As the initiator of this thread I haven't formed a final decision yet on rather I am gong to use it every day or not, but I have decided, for me, the answer to the question of useful or waste of energy seems clear, it is useful. On the other hand, it does take a while to get use to all the counting.
<

I certainly hope it is useful - thank you. As with anything new, it takes awhile to get used to it, but soon you will not be counting points from distribution often, since you memorize the Basic Shapes themselves, so you know that if you see a 5-4-3-1 it's 13, if you see a 4--4--3-2 it's 10 etc. I first add the Shape and the Controls then go "back" to the HCP which you count anyway. This gives me a perspective on how the OTHER tables would treat this hand and how different the Zar Points view is. A 5-4-3-1 with 2 A and a K is already 18 Zar Points ahead, while a 4-3-3-3 with a K is HALF that (only 9) even though they might have the same amount of, say, 13 HCP. The first hand is in the "Second Division" of opening (31+ Zar Points) while the other one belongs to the garbage bin :-) I'd take advantage of both, since the field will threat them as 13 HCP hands basically, plus a couple of points from distribution either by Goren or Bergen. So they ALSO see these hands differently, but by 2 points, while I see them different by DOUBLE that, or 4 of "their points"(since Zar Points are roughly 2 times lighter than Goren, like the requirement of 52 for a Game against 26 for Goren - you adjust to 8 Zar Points to 4 of the "other" points).

Do you make adjustments as the bidding progresses? Sure - you just use your head as usual :-)

*** Misho wrote:
>
Welcome to forum! You can explain the bidding ideas in a thread about unnatural systems for example...
<

Thank you. I may post here the BASIC ideas of the Zar Points Bidding and get an earlier feedback actually. That would be great! I may post a short description of the ideas - like 20 lines for example. You'll see the basics immediately without the need to jump into the sophisticated relays and footprints and "non-rounded coefficients" (for example an A is 6.18 Points etc.). Just the fundaments on which the system stands (besides the Zar Points Evaluation which you already know) – easy to understand indeed.

Make it a great day:

ZAR

[Zar]

Hi all:

I found another thing worth commenting on:

*** Erick wrote
... you open 1♠ on this hand ♠AQxxx ♥Kxxx ♦Qxx ♣x (zar point 27), and partner responds 2♣. I think the value of this hand has gone down... I suspect that subtracting a trick (5 points?) for a singleton opposite length would improve their accuracy.
<

This is an IMPORTANT consideration, which I have discussed with a number of former and current world champions indeed. So should we DECREASE the hand's value by 5 points, should we leave it AS-IS, or should we INCRESE the value by 5 points? The answer is (as usual) simple - it depends :-)

Depends on 2 things:
- side fit in the partnership;
- footprints in clubs (there are many more things on the website besides the "Never Miss a Game Again" article).


1) The side fit.
Let us consider these 2 hands of the player who bids 2C after the opening of 1S:

- ♠xx ♥QJx ♦KJ10 ♣KQxxx, with 12 HCP: bids 2C and rebids 2NT to show the values in the unbid suit and NT orientation

- ♠KJ10x ♥AJx ♦--- ♣Axxxxx, with 13 HCP: bids 2C to enable his PD evaluate his club holdings and rebids 3S.

With the first hand you'll have a hard time moving the cards around on any contract ...

With the second one, the SINGLETON is golden - it puts you at a GRAND with 87%, assuming that either trumps are not 4:0 or you have the filler trumps (10 and 9) if they ARE 4:0. Here is where the percentage comes from - [ 84% (36% for the 3:3 clubs + 48% for 4:2) + 3% (the heart-fines' 50% in half of the 5:1 (14%) when the singleton is after the A so you don't get overruffed) for a total of 87%]. Do you play 87% GRANDS? :-)


2) The clubs footprint.

The first hand has a footprint of 1, while the second one - 0. "Misfit" with 0-footprint and a side fit is a powerhouse.

I am sure we all realize the difference of the value of this singleton in the partner suit. Bottom line - re-evaluating at the first round is a no-no. Wait for the second round in such forcing situations and then re-evaluate. And yes - Zar Points make deductions in various situations and re-evaluations on as-you-go basis.


Cheers:

ZAR

[inquiry]

I have been playing with Zar's Bidding machine using hands grabbed from the myhands site at part score, game, and slam level (and from fairly large tournments with lots of participants).

To use it yourself, get hand info quickly from www.bridgebase.com/myhands, and fiind the ZAR bidding machine at the following link.

Zar's cool bidding machine

Ok. First, thing. As pointed out in his article, when using Zar points and the like, you must pay attention to controls in suits, and the like. Here is a slam hand that Zar's machine says the correct contract is 6.8♠'s, but of course, you are off an ACE so clearly the correct contract is 6♠. We all know how to use blackwood. I find the estimate is off frequently with one losing ACE in form like this example.

Scoring: IMP

---

West North East South

 -     -     -     2NT
 Pass  3♣    Pass  3♦
 Pass  3♥!   Pass  3♠
 Pass  4NT   Pass  5♣
 Pass  6♠    Pass  Pass
 Pass  
ZAR points = 66, Zar contract 6.8♠ by south

Here is a "partscore" one using the bidding machine.

Scoring: IMP

---

West North East South
 -     -     -     1♣
 Pass  3NT   Pass  Pass
 Pass  
What did the machine say? It said north had 25 ZAR points and recommended opening. If you swap South's spades and diamonds, the points still is 25, but the machine recommends pass. This follows the concept expressed in the article to open with 25ZAR points and four card+ in spades, I guess. The combined ZAR points is only 49, not enough for game. Here the bidding machine seems to fall down. It recommends a contract of 0.0♣, it seems like 2♣ is makable. In the actual event, however, overbidding was rampant NS. With 3NT a very popular contract (and as you can see, even 2NT can not make on a ♦ lead). This hand was played at 75 TABLES, at which 2NT/3NT was played at 26 tables, and 4♣/5♣ at 12 more tables, and 3♣'s at a ton of tables. At my table, we played 2♥NS when my partner choose to open 1♥ playing 5 card majors with south hand.. After a negative double, and my partner's pass, I balanced back in as north to 2♥'s. But here, ZAR's bidding machine clearly warns against overbidding.

This next hand shows a somewhat problem with the ZAR machine as presented. It ignores the location of honors/controls/points.

Scoring: IMP

---

West North East South
 Pass  Pass  1♣    1♠
 Pass  Pass  Dbl   2♦
 2♥    2♠    3♥    4♠
 Pass  Pass  Pass  

Having said that, the Zar points LOVES south's hand (32), and the suggested contract is 4.6♠. Even though the ♣K is totally wasted, it takes a ♦ lead and the ♠K off side doubleton (instead of tripleton) to beat this given the ♦Q is falls. And practically, everyone in ♠ made at least 10 tricks. Also note, the EW pair does very well in ♥ as well, with 4H played from one side laydown, and 4♥ from the other requires ♣ lead to set.

All in all, it was fun using ZAR machine and it seems to be a quick and dirty reasonable approximation, but as the three examples above show, the machine ignores some logis. In first, the fact that you are off an ace, in the second, that a part score is availabe in 2♣ (hard to stop there), and in the third? Well you want to be in 4♠ anyway, but it points out this mathematical machine doesn't factor into its calculations the location of honors.

[Flame]

About these example.
The first one, i would like a hand estimating machine to tell me that these hands is 6.8, because there are 13 tricks here, Id give the system 100% here.
hand 2 - oviously the system is wrong giving it only 0.0
hand 3 - i think 4.6 is a bit higher but not too much.

[inquiry]

Flame, on Apr 6 2004, 10:17 AM, said:

About these example.
The first one, i would like a hand estimating machine to tell me that these hands is 6.8, because there are 13 tricks here, Id give the system 100% here.
hand 2 - oviously the system is wrong giving it only 0.0
hand 3 - i think 4.6 is a bit higher but not too much.

Well on hand one, they will take their ♦A, or at least could take their ♦A, so I think 13 tricks is going to be tough to take after that one.

On hand 3, you go down on a ♦ lead. As the defense can manage a ♠, a ♦ ruff and two ♥'s. Fact is, not an easy defense to find. But they can start with two ♥ and then switch to a ♦, but the temptation to lead through ♣s was just too great.

[Zar]

>>> ZAR points = 66, Zar contract 6.8♠ by south
<
Conventions are often barred in many bridge clubs, but even in the high-stake clubs in London the one convention allowed everywhere is … Blackwood. Zar Bid Machine doesn’t “allow” even Blackwood, though :-) It just calculates points (Goren, Bergen, and Zar) and shoots. No “if”s, “but”s, and “about”s, so ... have mercy, please :-)

>>> What did the machine say? It said north had 25 ZAR points and recommended opening.
<
You probably mean SOUTH here ...

>>>If you swap South's spades and diamonds, the points still is 25, but the machine recommends pass. This follows the concept expressed in the article to open with 25ZAR points and four card+ in spades, I guess.
<

Correct – with 25 (only) you get an upgrade of 1 pt (just enough to open) if you hold the spades suit. I have to tell you that I was really surprised that several world champs mentioned that 1 Zar Point for holding the Spades suit is NOT enough! They thought (independently of each other) that 2 Zar Points is the correct upgrade.

>>>The combined ZAR points is only 49, not enough for game. Here the bidding machine seems to fall down. It recommends a contract of 0.0♣, it seems like 2♣ is makable.
<

Thank you for pointing this out – I am going back to Toronto for Easter and I’ll fix that. With 49 Zar Points and 8-card fit it will certainly give you 3.40 in the longest fit. Thanx again (no idea off the top of my head why it’s doing it, but I’ll fix it by the end of the week – I noticed that if you increase the Controls of N from 2 to 4 it gives you correctly 3.80 Clubs ...).

Cheers:

ZAR

[Flame]

inquiry, on Apr 6 2004, 10:22 AM, said:

Flame, on Apr 6 2004, 10:17 AM, said:

About these example.
The first one, i would like a hand estimating machine to tell me that these hands is 6.8, because there are 13 tricks here, Id give the system 100% here.
hand 2 - oviously the system is wrong giving it only 0.0
hand 3 - i think 4.6 is a bit higher but not too much.

Well on hand one, they will take their ♦A, or at least could take their ♦A, so I think 13 tricks is going to be tough to take after that one.

On hand 3, you go down on a ♦ lead. As the defense can manage a ♠, a ♦ ruff and two ♥'s. Fact is, not an easy defense to find. But they can start with two ♥ and then switch to a ♦, but the temptation to lead through ♣s was just too great.

Zar points imo arent suppose to tell you what is the right contract, they suppose to help you estimate the hand potential. the machine is giving you aresult like 6.8S is a cool thing but the machina shouldnt be alowed to transfer information like number of aces , or else it will be 100% accurate and 100% useless, I was happy with the 6.8 result because the machine got it right, there are 13 tricks to take.
At least in natural system this kind of estimate is just what you need. The process in slam bidding is usually, first check if there is slam potential (and this is what the machine answer for was yes) then if that exist check if we dont have 2 losers , meaning missing two aces, or missing a control in a suit. and same idea for grand.

[inquiry]

Well, Zar and Flame, I do not accept your characterizations of what I said as fair interpretation. It is true you can't make 7, and I noted not once but twice that this is understandable and not a real problem. First I said....

"Ok. First, thing. As pointed out in his article, when using Zar points and the like, you must pay attention to controls in suits, and the like. " This not only proved that I read his articles, it shows that I understand that making sure you are not off two quick tricks in one suit or an ace in grand slam is important.... This was a point he made in his articles, and on I repeated. I followed it up with, "Here is a slam hand that Zar's machine says the correct contract is 6.8♠'s, but of course, you are off an ACE so clearly the correct contract is 6♠. We all know how to use blackwood." Clearly stating we would not bid to Grand Slam even if we are the most ardent ZAR points supporter without checking.

Now Zar's sarcasim about using conventions aside, which I found humorous, a second post point out that Blackwood would have prevented bidding grand slam is hardly needed... since I said that myself, as a way of pointing out the obvious to anyone who plays with the ZAR bidding machine... I assure you, I already understood this limitation in the bidding machine and in the point counting part without the machine.

Ben

[Flame]

inquiry, on Apr 6 2004, 01:22 PM, said:

Well, Zar and Flame, I do not accept your characterizations of what I said as fair interpretation. It is true you can't make 7, and I noted not once but twice that this is understandable and not a real problem. First I said....

"Ok. First, thing. As pointed out in his article, when using Zar points and the like, you must pay attention to controls in suits, and the like. " This not only proved that I read his articles, it shows that I understand that making sure you are not off two quick tricks in one suit or an ace in grand slam is important.... This was a point he made in his articles, and on I repeated. I followed it up with, "Here is a slam hand that Zar's machine says the correct contract is 6.8♠'s, but of course, you are off an ACE so clearly the correct contract is 6♠. We all know how to use blackwood." Clearly stating we would not bid to Grand Slam even if we are the most ardent ZAR points supporter without checking.

Now Zar's sarcasim about using conventions aside, which I found humorous, a second post point out that Blackwood would have prevented bidding grand slam is hardly needed... since I said that myself, as a way of pointing out the obvious to anyone who plays with the ZAR bidding machine... I assure you, I already understood this limitation in the bidding machine and in the point counting part without the machine.

Ben

Ben
Let me expain maybe i wasnt clear.
I would like my hand evaluation process to give me a 6.8 result on these pair of hands, because this is the potential of pair, therefore i said that for me on this hand the zar machina was 100% accurate.

[inquiry]

Flame, on Apr 6 2004, 01:50 PM, said:

Let me expain maybe i wasnt clear.
I would like my hand evaluation process to give me a 6.8 result on these pair of hands, because this is the potential of pair, therefore i said that for me on this hand the zar machina was 100% accurate.

Ah, I stand corrected... yes. I am happy with the 6.8 ♠ estimate myself. I don't see this as a problem at all. I am not bdding the grand slam without asking for controls here...

Ben

[Zar]

*** Ben wrote:
>>> Now Zar's sarcasm about using conventions aside,
<

No, I am not sarcastic, Ben – I just talk this way :-) I really truly appreciate and think on any input on Zar Points and I assure you I take them all seriously (despite the fact that I cannot address them all the way I’d like to).

>>> I already understood this limitation in the bidding machine and in the point counting part without the machine.
<

No doubt.
>
I would like my hand evaluation process to give me a 6.8 result on these pair of hands, because this is the potential of pair, therefore I said that for me on this hand the zar machina was 100% accurate. I am happy with the 6.8 ♠ estimate myself. I don't see this as a problem at all. I am not bidding the grand slam without asking for controls here...
<

Yes, I also think we paid too much attention to this one. Going beyond Game without having an idea about Controls and Aces is not worth discussing :-)


Cheers:

ZAR

[hrothgar]

As I have noted before, I think that much more analysis is required before we can make a meaningful assessment regarding the accuracy of Zar points.

From my own perspective, I would very much like to see some "pure" research.

For example, consider the following experiment.

Step 1
Randomly deal a million hands in which North holds

AT63
K952
Q84
J7

and South, East, and West are unconstrained.

Step 2
Use a double dummy engine to sort the hands based on the number of tricks that North South can take.

Step 3
Bucket 1 = the set of all hands where N/S can take 13 tricks
Bucket 2 = the set of all hands where N/S can take 12 tricks
...

Step 4

Look at all of the South hands in Bucket 1
Calculate hand strength using a range of hand evaluation techniques
[Zar Points, Bum Rap, Goren Points, Losers, ...]

Repeat for bucket 2, bucket 3, ...

Step 5

Calculate a standard set of summary statistics [Max, Min, Standard Deviation, interquartile range] for each hand evaluation technique.

I argue that the shape of the probability density function of hand strengths can be used to measure the accuracy of the evaluation technique.

[Fluffy]

Think you all missed an important point, regardless you distribution having some HCP has huge importace on competitive biddings because Opponents do not have your high cards!, ZAR´s can be more accurate on not competitive but... is it better on competitive, its agresiveness can deceive opponents? or maybe help them to play when you failed to bid?: finding you are strong->balanced hand or shaper ->poor hand.

Anyway there is no better good hadn evaluating system by itself, I just use HCP at start so I don´t differ from the rest tables, but when very unbalanced or finding a fit and trying for a game/slam I quickly switch to either count losing tricks or missing Key cards, mixing systems is probably the best system.

[tysen2k]

hrothgar, on Apr 8 2004, 07:58 AM, said:

For example, consider the following experiment.

Step 1
Randomly deal a million hands in which North holds

AT63
K952
Q84
J7

and South, East, and West are unconstrained.

This is exactly what Binky points do, except that instead of taking just the one North hand in your example, it was based on over 700,000 hands. Additionally, you don't want an evaluation method that is best opposite an "average hand", you want one that is weighted over all the hands that partner can have. Binky takes the evaluation method that is best simultaneously for both players instead of just one.

Binky and other double-dummy evaluators can give some insight into competitive bidding as well. Based on your own hand, you can make some estimations about how many tricks the opponents can take as well. Not as accurate as our own tricks, but still... You can generate a sort of "total tricks" estimate and use that for preemptive or competitive bidding. So if you have a shapely hand, you may not have that many "points" but you see that you have no defense and can bid it up.