Zar points, useful or waste of energy

[tysen2k]

*** Zar (answering Mikestar) wrote:

Where is that method? :-) Utter it and I’ll run it through the millions of boards I have run Goren and Bergen through. So you can substitute the “here is a method” with “there is no method” :-)

 

I’d be HAPPY to see a PROOF (as opposed to IHMO) that ANY other method is better.

 

Not only that – I’d USE it instead of Zar Points :-)

As I've said in previous posts and Mikestar has echoed, the evaluation scheme

 

A = 4.5

K = 3

Q = 1.5

J = 0.75

T = 0.25

 

Plus distribution of 5/3/1 for void/single/double is more accurate than ZAR.

 

This ratio of values for high cards (4.5/3/1.5/0.75 or 6/4/2/1) is not new. The Dallas Aces were using 3/2/1/0.5 in the 70's.

 

But the ZAR distribution scheme is simply less accruate than 5/3/1. Yes using 4.5 for aces involves fractions, but it allows me to use my existing bidding methods. I don't have to worry if my strong club requires 30 or 31 ZAR or whatever. To me, if I have to change my bidding methods, it just isn't worth it.

 

I have done extensive studies on many evaluation systems (see my previous posts). Zar, while I admire your research I do question a lot of your methods for determining how accurate a system is. One of your reasons that ZAR is more accurate is that ZAR has more "separation power" and a higher standard deviation than standard (meaning that there are more possible values and more spread out values). This does not give accuracy. I can create an evaluation scheme that doesn't give any values to high cards, counts the ♣2 as 1 point, the ♦2 as 2 points, ♥2 as 4, ♠2 as 8, ♣3 as 16, etc. I could make this scheme have 100 times more separation power than ZAR. Should I claim I've found a new system that's 100 times more accurate than ZAR?

 

You also seem to sometimes go backwards in your assigning of accuracy. You find hands that make game or slam and then see what % of Goren, ZAR, etc. would bid that high. That's going the wrong way. You should first take hands and see where the points say you should be, then assume you bid there and see how well you do. Maybe the points say game, but the hand doesn't make it. Look and see how far you were off and how much that would have cost you. You're finding hands that already make game and then seeing if you would have bid it.

 

Zar, don't get me wrong. I admire people trying to break new ground in research like this. Just make sure you're measuring the right thing.

 

Let me know if you want more information about my studies and findings.

 

Tysen

[Zar]

*** tysen2k wrote: Plus distribution of 5/3/1 for void/single/double is more accurate than ZAR.

<

 

Plus, you forgot to say IMHO :-) How many boards did you test it on? Using 0.25, 0.75 etc. is not for “at the table’ use – otherwise I’ll use the real computed coefficients for Zar Points like 6.18 for an A etc. You have to be “in line” with any comparison. I certainly have checked 1-3-5 also, but with Goren – no comparison. You are certainly welcome to check it yourself. In fact, I would SUGGEST you check it first and then “claim” 1-3-5 is better.

 

>

The Dallas Aces were using 3/2/1/0.5 in the 70's. But the ZAR distribution scheme is simply less accurate than 5/3/1.

<

 

Again – “simply” doesn’t cut it. Check it and then say “simply” or “not-simply” :-)

 

>

You should first take hands and see where the points say you should be, then assume you bid there and see how well you do. Maybe the points say game, but the hand doesn't make it.

<

 

You haven’t read it at all then ... That’s exactly what I do. All dozens of millions of boards have been INDEPENDENTLY played by a DD-program – it’s not me who decides this and that. Anyway – you certainly can use 1-3-5 or 0.25 – 0.75 etc. It’s all a matter of choice:

 

ZAR

[mikestar]

I've never published the method--but Tysen advocates something very similar and slightly more accurate that has been seen before.

 

To do testing, simply change the Goren distribution figures from 1-2-3 to 1-3-5 and chance the HCP to 4.5-3-1.5-1 --even with no further adjustments it tracks more closely with Zar points than the other methods.

 

The figures usch as .133 were used to describe the degree of discrepancy between 1-3-5 and Zar--these are not used at the table.

 

At the table I would count HCP 4-3-2-1, distribution 1-3-5 then compare the number of aces and queens in my hand, adjusting 1/2 point plus for each excess ace or 1/2 point minus for each excess queen. This is quite simple enough for a beginner and uses the same point count targets as all beginners are taught.

 

As for the discrepancy shapes, some Zar evaluations are a bit strange -- you are the only authority who asserts that 6-5-2-0 is better than 6-5-1-1, absent inferences from the bidding.

[Zar]

** mikestar wrote: To do testing, simply change the Goren distribution figures from 1-2-3 to 1-3-5 and chance the HCP to 4.5-3-1.5-1 --even with no further adjustments it tracks more closely with Zar points than the other methods.

<

 

This is a good spec – I’ll run it through, despite the fractional numbers.

 

>

The figures such as .133 were used to describe the degree of discrepancy between 1-3-5 and Zar--these are not used at the table.

<

 

I am not sure I understand the table (I assume you are talking about the previously published table on this topic). Can you elaborate a bit, please?

 

>

As for the discrepancy shapes, some Zar evaluations are a bit strange -- you are the only authority who asserts that 6-5-2-0 is better than 6-5-1-1, absent inferences from the bidding.

<

 

I wish I had your problems, Mike :-)

 

ZAR

[Flame]

"6-5-2-0 is better than 6-5-1-1" Im not an autority by IMHO ;) this is right.

[mikestar]

Shape      (1-3-5 tricks  minus Zar tricks)

4-4-4-1                    +.400   

5-3-3-2                    -.267 

5-4-4-0                    +.467

6-3-2-2                    -.333

6-3-3-1                    -.200

6-5-1-1                    +.400     

6-5-2-0                      +.200

7-2-2-2                      -.200

7-3-2-1                      -.267

7-4-1-1                      +.200

8-3-2-0                      -.200

 

 

The first entry will serve as an example. 1-3-5 gives 4-4-4-1 3 distribution points vs. 0 for 4-3-3-3. Dividing by the 3 points per trick for the 1-3-5 scale, this is 1 trick. Zar counts 11 points for the 4-4-4-1 vs 8 points for 4-3-3-3 for a difference of 3 points. Dividing by Zar's 5 points per trick, this is 0.6 tricks. So 1-3-5 rates 4-4-4-1 0.4 tricks higher than Zar does. The same methodology was uses for all shapes.

 

I excluded superfreaks (too infrequent to matter much) and those cases where 1-3-5 and Zar agree withing the limits imposed by the different scales-- a three point scale and a five point scale cannot agree exactly for fractional trick values, but if 1-3-5 says something is 1 1/3 tricks and Zar says it is 1.4 tricks, this is not really a disagreement about the item's value.

[mikestar]

>

Bergen is not intended for overall evaluation, but for the specific purpose of determining whether to open.

<

 

True. BUT you can always apply the Culbertson’s Rule stating that “Two opening hands make a Game” – to ANY opening-hand evaluation system actually. And this converts the evaluation system into ab overall evaluation system - think about it.

 

Because it is possible doesn't mean it's appropriate. Culbertson himself passed hands that had opening-bid playing strength by his own evalualtion methods but had insufficient defense (honor tricks).

 

Bergen's method intentionally underates unbalanced shapes to reflect his judgement about how much defense is needed and how much negative revaluation in case of misfit should be risked. You would open a 6-5-2-0 hand with 7 HCP and 2 contols at the 1 level, Bergen would not, insisting on 9 HCP. This is not a difference in the evaluation of the trick taking ability of the hands, this is a differnce in opening bid philosophy--Bergen chooses to be less agressive than you in this area. (Bet he's more aggressive with preempts!)

[Zar]

*** mikestar wrote: The first entry will serve as an example. 1-3-5 gives 4-4-4-1 3 distribution points vs. 0 for 4-3-3-3. Dividing by the 3 points per trick for the 1-3-5 scale, this is 1 trick.

<

 

The 5 Zar Points per trick come based on HCP, Controls, and distribution. Where do the 3 points per trick come from in the 1-3-5 count? Don't get me wrong - I just cannot see (or don't know) where this comes from.

 

In other words, what is an opening hand in the 1-3-5 count for example (certainly added to HCP or controls or whatever else is used). Do you still open with 13?

 

ZAR

[mikestar]

Zar,

 

Yes, you still open with 13--that is the whole point of my advocacy of 1-3-5 you can use the same magic numbers youv'e used for your whole bridge career. It may be 1-3-5 is slightly less acurate than Zar it may be that is is slightly more accurate, but the difference is in any case nowhere nearly as great as the difference between Zar points and other point count method. Let's assert without proof that 1-3-5 is only 85% as accurate but is twice as easy to use because you have been programmed for years to think in terms of 13/26/33/37, instead of 26/52/62/67. If this were true. which should a beginner/intermediate use? And if 1-3-5 is 98% or 102% or Zar's accuracy the answer is obvious.

 

My own experience is that Zar points works great as an after the fact analytical tool but gives me a brain cramp at the table because of the unfamiliar numbers. IF the superiority or Zar points is sufficent, this price is worth paying, but if I'm fairly close with something else that I can count in my sleep, the price isn't worth paying.

[inquiry]

Shape       (1-3-5 tricks  minus Zar tricks)

4-4-4-1                    +.400   

5-3-3-2                     -.267  

5-4-4-0                     +.467

6-3-2-2                     -.333

6-3-3-1                     -.200

6-5-1-1                     +.400     

6-5-2-0                      +.200

7-2-2-2                      -.200

7-3-2-1                      -.267

7-4-1-1                      +.200

8-3-2-0                      -.200

 

 

The first entry will serve as an example. 1-3-5 gives 4-4-4-1 3 distribution points vs. 0 for 4-3-3-3. Dividing by the 3 points per trick for the 1-3-5 scale, this is 1 trick. Zar counts 11 points for the 4-4-4-1 vs 8 points for 4-3-3-3 for a difference of 3 points. Dividing by Zar's 5 points per trick, this is 0.6 tricks. So 1-3-5 rates 4-4-4-1 0.4 tricks higher than Zar does. The same methodology was uses for all shapes.

 

I excluded superfreaks (too infrequent to matter much) and those cases where 1-3-5 and Zar agree withing the limits imposed by the different scales-- a three point scale and a five point scale cannot agree exactly for fractional trick values, but if 1-3-5 says something is 1 1/3 tricks and Zar says it is 1.4 tricks, this is not really a disagreement about the item's value.

I think you are short changing ZAR's method in this description, although he didn't mention it above. Upon intial counting, ZAR would count 4333 as 8, and 4441 as 11 as you point out. But once a fit is found, the 4441 is worth more than 11. He would add two more points, to come to a full 13. In otherwords, 4441 (with a fit) would be worth a full five points more (and one level higher) than a hand with 4333. In addition, there could be more points added for 4441 if a superfit is found, at least that is my reading. So if a fit exist, ZAR point count shows the full 1.0 trick that you claim for the 1-3-5, and may indeed show more.

 

Ben

 

PS, as the initiator of this thread, I have been "researching" on my own the use of ZAR points for making game/slam/grand slam decisions, and I must say, that IMHO (Zar will hate that), they are most definetly worth the "trouble" to learn. And the good thing is, it really isn't much trouble at all.

[mikestar]

Ben,

 

Thus far I have only been discussing initial valuation. As to revaluation in case of a superfit 2 points per extra trump is fairly equiavlent to Zar's simplified 3 points per extra trump. I'll publish details about revaluation later.

[Zar]

Mike,

 

Let me get this straight since I intend to run some boards through the 1-3-5 valuation (some means like 100K of course, rather than a couple :-). You say "programmed for years to think in terms of 13/26/33/37, instead of 26/52/62/67" and I take that as you add the 1-3-5 for xx-x-void to the HCP and "flag" a Game if you get to 26, Small with 33, and Grand with 37. Prety much like with Goren, correct?

 

It will be the same set of boards that were reported in the "Reserch" section of the book on the website (where the xx-x-void are calculated via 1-2-3 though). Let me know.

 

Cheers:

 

ZAR

[tysen2k]

Thus far I have only been discussing initial valuation. As to revaluation in case of a superfit 2 points per extra trump is fairly equiavlent to Zar's simplified 3 points per extra trump. I'll publish details about revaluation later.

And see my articles on revaluation (although long and detailed). I think I mentioned them earlier in this thread:

 

[improving Hand Evaluation Part 1]

http://tinyurl.com/25huc

 

[improving Hand Evaluation Part 2]

http://tinyurl.com/383e6

 

 

Zar, in reference to how many hands I've tested it on it's over 2.8 million.

 

Let me just show some hard data so we're not talking about "IMHO."

 

           Tricks  Tricks  Tricks  Error   Error
          Real    ZAR     5/3/1   ZAR     5/3/1
4-3-3-3   0.000   0.000   0.000   0.000   0.000
4-4-3-2   0.296   0.400   0.333   0.235   0.030
5-3-3-2   0.339   0.600   0.333   1.061   0.000
5-4-2-2   0.595   0.800   0.667   0.447   0.055
6-3-2-2   0.660   1.000   0.667   0.655   0.000
4-4-4-1   0.810   0.600   1.000   0.133   0.109
5-4-3-1   0.864   1.000   1.000   0.241   0.241
6-3-3-1   0.918   1.200   1.000   0.276   0.023
7-2-2-2   0.999   1.200   1.000   0.021   0.000
6-4-2-1   1.154   1.400   1.333   0.286   0.152
5-5-2-1   1.183   1.200   1.333   0.001   0.073
7-3-2-1   1.208   1.600   1.333   0.290   0.030
5-4-4-0   1.519   1.200   1.667   0.127   0.027
6-4-3-0   1.624   1.600   1.667   0.001   0.002
5-5-3-0   1.643   1.400   1.667   0.054   0.001
7-3-3-0   1.697   1.800   1.667   0.003   0.000
6-5-1-1   1.703   1.600   2.000   0.008   0.063
7-4-1-1   1.712   1.800   2.000   0.003   0.032
7-4-2-0   1.923   2.000   2.000   0.002   0.002
6-5-2-0   1.964   1.800   2.000   0.018   0.001
              
                         Totals   3.862   0.842

 

We're looking at how many more tricks you take with certain hand patterns over a 4333 hand. The first column shows what the actual average difference is over the 2.8 million hands. The second column is what ZAR predicts the difference will be. Third column is what 5/3/1 predicts. Fourth and fifth are the squared errors weighted by frequency. The totals on the bottom show that ZAR has over 4.5 times as much error as 5/3/1. Note that I'm using 3 points per trick for 5/3/1 even though it should be slightly less since 26/29/33/37 aren't perfectly 3 point steps. If I change it to a little more than 3, then the 5/3/1 count gets even better.

 

Tysen

[mikestar]

Zar,

 

you understand me correctly.

[Zar]

Hi, guys:

 

I ran the Grand Slams for WTC and for the 1-3-5 evaluation.

 

I DO realize that in the Slam / Grand area Zar Points are hard to come close to and that 4S/4H (Games) is the more important one to get right. But still, here are the runs:

 

 

7 (GRANDs, 7813 boards)========Overall Results ===========

 

GOREN Points ( HCP + 3-2-1> 36 ) got 135 contracts

The WTC (Number of tricks > 12) got 667 contracts

The GOREN 135 ( HCP + 5-3-1> 36 ) got 1231 contracts

Basic Zar Points (no fit points) got 1925 contracts

Fit Zar Points (+3 extra trump) got 3760 contracts

 

I'll run the Games ( 5C/5D and 4S/4H) probably during the weekend (will try earlier). I'll also ZIP the files and make them available for download on the site.

 

Again, Grand Slam area is the "extreme" for Zar Points so the comparisson in the Small Slams and Games would be more interesting. One thing I noted immediately, though, is that 1-3-5 is almost 10 TIMES better than Goren 123 - it is much more interesting to go through all the 7813 boards and observe the specific differences.

 

Cheers:

 

ZAR

[mikestar]

I'm inclined to think that putting up with the brain cramp while changing my ways might be worth it.

 

Did you also allow for +1/2 HCP for each ace and -1/2 HCP for each queen in the 1-3-5 calculations? If not, then part of Zar's superiority is the more accurate honor count.

 

A fit version of 1-3-5 is easily defined-- add 2 points per extra trump instead of Zar's 3 to reflect the different size of the scales.

 

I suspect these two changes (or one if you already did the HCP adjustment) will bring 1-3-5 closer to Zar. It is also possible that the targets should be one point lighter--American beginners are taught 26 for game and European beginners are taught 25.

 

I wouldn't be surprised to see that Zar is still superior even with these adjustments to 1-3-5, but for me the test is how much superior--how much improvement do I get in exchange for the mental effort.

 

For anyone who can adjust to using Zar at the table easily, I'm sure the effort is worth it. I can envision that many people would find changing the targets easier than using half points as I advocate or quarter points as in BUM Rap. For me I find it harder to change targets.

[mikestar]

I wanted to share something I came up with during my mental meanderings aroung Zar points. Here is a formula for converting HCP/Goren point/Bergen point etc. bidding requirements to Zar points. First determine an appropriate base shape for the bid. For bids such as opening one bids that can be unbalanced but don't show extreme shape, I would suggest using 5-4-2-2: note that its 12 Zar DP is halfway between 11 Zar DP for 4-4-4-1 (the weakest unbalanced patern), and 13 Zar DP for 5-4-3-1 (the most common unbalanced pattern).

 

We assume that the point count requirement applies to a hand of the base shape with a normal number of controls. Proceed as follows:

 

1. Convert the requirement to HCP if it isn't already in HCP, by deducting the distribution points for the base shape.

2. Multiply the HCP by 1.3 to convert HCP to Zar honor Points.

3. Add the Zar DP for the base shape.

 

Some examples:

 

Goren opening one bid (13 Goren points):

 

Subtract the 2 Goren DP from 13 yielding 11 HCP.

Multiply 11 HCP by 1.3 yielding 14.3 Zar HP--round to 14.

Add the 12 Zar DP for 5-4-2-2 shape to the 14 Zar HP, yielding 26 Zarpoints B)

 

A Rule of 18 opening:

 

18 - 9 (Bergen value of 5-4-2-2) = 9

9 * 1.3 = 11.7, round to 12

12 + 12 = 24 Zar points

 

 

Precision 1C (with unbalanced hand):

 

16 HCP, no subtraction.

16 * 1.3 = 20.8, round to 21

21 + 12 = 33 Zar points

 

Romex Dynamic NT (with unbalanced hand):

 

(Converting Rozenkranz's more complex requirements to "Rule of 27")

 

27 - 9 =18

18 * 1.3 = 23.4, round to 23

23 + 12 = 35 Zar points

 

This technique might be useful for setting Zarpoint standards for premepts (with different base shapes, of course). For example, thet's say our partnership's minumum weak two is something like KQxxxx xxx xx xx. We chose 6-3-2-2 as our base, giving 13 Zar DP. Now

 

5 * 1.3 = 6.5, round to 7

7 + 13 = 20 Zar points

 

Note that we don't do any of this calculating at the table--this is done when we are coverting our system notes to using Zar points. At the table we just count Zars.

Edited April 24, 2004 by mikestar

[Zar]

*** Mikestar wrote: I'm inclined to think that putting up with the brain cramp while changing my ways might be worth it.

<

 

I hope it’s not a typo and you didn’t mean “brain crap” :-)

 

>

Did you also allow for +1/2 HCP for each ace and -1/2 HCP for each queen in the 1-3-5 calculations? If not, then part of Zar's superiority is the more accurate honor count. A fit version of 1-3-5 is easily defined-- add 2 points per extra trump instead of Zar's 3 to reflect the different size of the scales.

<

 

None of these, Mike – just what you told me, HCP and 1-3-5. These +-½ will neutralize in most cases I believe, but if you insist I’ll put them in ...

 

>

I suspect these two changes (or one if you already did the HCP adjustment) will bring 1-3-5 closer to Zar.

<

 

The fit +2 will, that’s for sure.

 

>

It is also possible that the targets should be one point lighter--American beginners are taught 26 for game and European beginners are taught 25.

<

 

I am taught 24 :-)

 

>

I wouldn't be surprised to see that Zar is still superior even with these adjustments to 1-3-5, but for me the test is how much superior--how much improvement do I get in exchange for the mental effort.

<

 

I have the feeling I am pulling your teeth with these Zar Points :-) Have you ever worked harder? :-)

 

>

For anyone who can adjust to using Zar at the table easily, I'm sure the effort is worth it. I can envision that many people would find changing the targets easier than using half points as I advocate or quarter points as in BUM Rap.

<

 

These quarters and halfs and rounding stuff ... How come none of them is a brain cramp for you? Cannot seize to wonder :-)

 

ZAR

[mikestar]

[Mikestar post]

I'm inclined to think that putting up with the brain cramp while changing my ways might be worth it.

 

 

[Zar reply]

I hope it’s not a typo and you didn’t mean “brain crap” :-)

 

[mikestar reply]

Not a typo (for once!)

 

[mikestar post]

It is also possible that the targets should be one point lighter--American beginners are taught 26 for game and European beginners are taught 25.

 

[Zar reply]

I am taught 24 :-)

 

[mikestar reply]

Always were an agreesive game bidder, weren't you? ;-)

 

[mikestar post]

I wouldn't be surprised to see that Zar is still superior even with these adjustments to 1-3-5, but for me the test is how much superior--how much improvement do I get in exchange for the mental effort.

 

[Zar reply]

I have the feeling I am pulling your teeth with these Zar Points :-) Have you ever worked harder? :-)

 

[mikestar reply]

Well, yes--not at bridge however. It seems I always resist a new idea most strongly before adopting it.

 

You show both the ability and the willingness to defend your ideas with excellent supporting data--that counts for a lot. Many new ideas never got adopted by me because their inventors couldn't defned them or couldn't be bothered to do so.

 

[mikestar post]

For anyone who can adjust to using Zar at the table easily, I'm sure the effort is worth it. I can envision that many people would find changing the targets easier than using half points as I advocate or quarter points as in BUM Rap.

 

[Zar reply]

These quarters and halfs and rounding stuff ... How come none of them is a brain cramp for you? Cannot seize to wonder :-)

 

[mikestar reply]

I don't actually count them: noticing a couple of aces and no queens, I add a point.

 

My bridge history with regard to hand evaluation has involved many different point count methods (plus non-PC methods like the LTC). All of the methods had 26 for game, however much they differed otherwise (with the exception of a couple which clearly had no merit--for example, one with a 5-4-3-2 scale for honors). So the equation of 26=game is more firmly rooted in my unconsious than any method of counting to 26. I think it fairly likely that my experience is atypical.

 

In any event, the fact that I am considering such a radical overhaul of my methods is a testimony to the great merits of Zar points--I don't have the time or mental energy to waste wrestling with something merely above average.

 

As a side note, I find it interesting that 1-3-5 even without a fit adjustment is so much better than Goren 1-2-3: you would think it would be more widley played, as the adjustment from 1-2-3 is so simple.

[inquiry]

Hi Zar,

 

I have a question. I was plugging through your example of 7 level grand slams and lookng at the hands. And I noted a few hands that the opitmal contract (double dummy solver) was 7 that I think 7 is not a good contract on.

 

This is when I noted that you don't show the EW hands, so for example if the double dummy solver will drop a singleton trump K offside to make slam missing 4 trumps would that show up as the optimal contract? Would the fact that a grand slam had precisely 50% to make, would it be included in the "grand slam" group if the hand actually dealt was one where 13 tricks could be made, but listed as a six level contract if it was one where six was limit by the position of the opponents cards? I note that most of the 63 ZAR point grand slams that I looked as so far, even looking at the hands (but not the opponents), that a small slam would be the preferred contract (actually as predicted by ZAR Points I guess).

 

Ben

[Zar]

** Mikestar wrote: the fact that I am considering such a radical overhaul of my methods is a testimony to the great merits of Zar points...

<

 

I am happy to see a “hardliner” like you doing it, Mike – thank you.

 

>

As a side note, I find it interesting that 1-3-5 even without a fit adjustment is so much better than Goren 1-2-3: you would think it would be more widely played, as the adjustment from 1-2-3 is so simple.

<

 

I mentioned in another thread (read all the 3 threads on Zar Points here) that “...the “1-3-5 method” suffers the same “merging” deficiencies as Goren (since they assign values to the SAME parts of the 39 shapes). Not as bad as Drabble, but still 6-3-3-1 is same as 4-4-4-1 or 5-4-3-1 for example, or 5-4-4-0 is the same as 7-3-3-0 etc. meaning having 2 additional cards in a suit may not be reflected in any way.” I am sure you wouldn’t like someone to pull-out 2 cards from your longest suit from time to time, while you are playing a high-stake rubber bridge :-)

 

Another VERY important point that remains unnoticed. If you check the records from the experiments and read “The Research” section of the book, you’ll see that Zar Points is #1 in the “Not OVERBIDDING” comparisons!!! Being #1 is a 2-side coin – bidding the most Games and Slams and NOT OVERBIDDING part scores on Games and Games on Slams. I would have never published Zar Points if they didn’t demonstrate their ability to NOT overbid and I was happy to see Zar Points leading the comparison in the “NOT-overbidding” contest (see the records on the site).

 

Otherwise here a system for the previous “GRAND-slam” experiment that will beat both Goren 5-3-1 AND Zar Points – just bid a GRAND every time the bidding comes to you :-)

 

ZAR

 

P.S. I posted this reply by mistake to the other thread first, sorry.

[Zar]

*** Ben wrote: I was plugging through your example of 7 level grand slams and lookng at the hands. And I noted a few hands that the opitmal contract (double dummy solver) was 7 that I think 7 is not a good contract on.

<

 

I see you really think of me as a VERY hard-working guy, while I am just smart :-) I don’t check every single board of the millions I have in the databases. ALL of them are only played on Double-dummy by the (same :-) computer. There is a couple of them off – sure, but that’s a drop in the sea.

 

Now, here is an IMPORTANT note for you – WHY is Double-dummy SHARP for analysis? Here is why. The Double-dummy programs indicate an average 1.0 tricks MORE than you and I would make AGAINST THE COMPUTER, simply because “these guys” never make a mistake allocating the missing cards, never play in ruff-and-discard, never jump against forks etc. However, there was a study on 25 MILLION plays calculating that the average defender in those 25 million plays gives away 1.1 tricks as a defender!!! Yes, you and me too, my friend. Defense is not flagged as the hardest part of the game by chance.

 

That’s why I put the “AGAINST THE COMPUTER” in caps above – because it’s different at the table where there are 2 other PEOPLE (rather than computers) who are often willing to help you out. And you see that the 1.1 and 1.0 are close to neutralizing each-other.

 

>

This is when I noted that you don't show the EW hands, so for example if the double dummy solver will drop a singleton trump K offside to make slam missing 4 trumps would that show up as the optimal contract?

<

 

The direct answer is “yes”, but see above.

 

>

I note that most of the 63 ZAR point grand slams that I looked as so far, even looking at the hands (but not the opponents), that a small slam would be the preferred contract (actually as predicted by ZAR Points I guess).

<

 

Yes, I am glad you noticed that – Zar Points were the best performer in the NOT OVERBIDDING comparison and I value that equally if not more than the best performance in bidding Games and Slams. See my reply to Mike above.

 

Cheers:

 

ZAR

[Zar]

I owe you an appology for the GRAND slam comparison - it turned out that I

have left a filter throwing away hands with over 31 HCP (I make all kinds of

experiments and this filter was left from previous series). BUT - the good news

is that I have now run the GRANDS through several different filters and the

results will be of interest to you.

 

First, the GRANS slam area with no filters, meaning that the HCP restriction

is 40 points. Here are the numbers:

 

 

HCP_3-2-1 1427

WTC 1543

HCP_5-3-1 2913

Zar_NoFit 3753

Zar_Fit 5729

 

 

So in this "No-Filters" GRAND slam area where the HCP restriction is 40 HCP,

we can say that:

 

 

1) HCP_5-3-1 performs 2 TIMES better than HCP_3-2-1

 

2) Zar_Fit performs 2 TIMES better than HCP_5-3-1

 

 

This is the "worst-case-scenario" comparison for both 5-3-1 and Zar, meaning

that the lower you go on HCP the better their relative performance.

 

Here are the numbers for GRANDS with less that 35 HCP:

 

HCP_3-2-1 1232

WTC 1424

HCP_5-3-1 2718

Zar_NoFit 3567

Zar_Fit 5543

 

 

Here are the numbers for GRANDS with less that 31 HCP:

 

HCP_3-2-1 135

WTC 667

HCP_5-3-1 1231

Zar_NoFit 1925

Zar_Fit 3760

 

 

Here are the numbers for GRANDS with less that 27 HCP:

 

HCP_3-2-1 0

WTC 103

HCP_5-3-1 133

Zar_NoFit 224

Zar_Fit 1098

 

 

You see that the more aggressive the contract (in terms of low HCP), the bigger

the advantage of the Zar Points method, which is expected.

 

Compared to the 5-3-1 method, the difference grows from 2:1 for anay GRANDS,

to 10:1 for the aggressive GRANDS with less that 27 HCP.

 

Basically the same 10:1 ratio holds for 5-3-1 against 3-2-1 in the aggressive area,

and the same 2:1 advantage holds in the 40 HCP are. So:

 

 

1) HCP_5-3-1 performs 10 TIMES better than HCP_3-2-1

 

2) Zar_Fit performs 10 TIMES better than HCP_5-3-1

 

 

I guess it is safe to say that at any range, Zar Points are as much better than the

5-3-1 method as the 5-3-1 method is better than the 3-2-1.

 

These differences will get smaller and smaller as the Level of the contract goes down,

and eventually will disappear at the low-level partscores, where basically "all

methods are good enough for the 1 Club contract" :-)

 

Cheers:

 

ZAR

[inquiry]

It will be interesting to compare the ZAR fit with 5-3-1 using the corrections for Fit that Mikestar mentioned, but these ZAR numbers seem very impressive. I have definetly started trying to use ZAR points evalution during my bidding, and have started redefining some of my raises in terms of Zar points.

 

Ben

[Zar]

*** Ben wrote: "It will be interesting to compare the ZAR fit with 5-3-1 using the corrections for Fit that Mikestar mentioned, but these ZAR numbers seem very impressive.

<

 

I think I have mentioned in a previous post - for the 5-3-1 ONLY the HCP plus the distribution assignments are calculated, and for Zar Points ONLY the basic points AND the +3 per supertrump (in the case of Zar_Fit method) - no other adjustments of any kind. Similarly, for Goren ONLY the HCP and the 3-2-1 points are considered, despite the fact that obviously no expert plays bridge without any adjustments :-)

 

Ben, on the "Cavendish" thread (which surprised me), I can send you the 2000-2003 comparisons (I don't have your email address). In two words - the approach there is MUCH more exhaustive and scientific, so to say - every contract is played against the "Average Cavendish Defender", menaing all the results are "calibrated" against every single table on the Cavendish, rather than picking a single number. I guess you'll like it, and I'll try to do a session from the 2004 the same way. I'll certainly discuss the Cavendish thread once I go through it.

 

Cheers:

 

ZAR