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Zar evaluation and 2004 Cavendish Invitational Pairs

#1 User is offline   inquiry 

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Posted 2004-May-13, 20:44

there has been several threads wondering how well ZAR point evaluation system works. Recently we had a chance to see a lot of hands from the 2004 Cavendish thanks the BBO Vugraph. So I wondered how well would ZAR evaluation do? Using the following simple rules, 52 and fit, bid game, 62 and fit bid slam, 67 and fit bid grand slam. The following caveats are applied,

!) assume system of bidding that can determine if off two keycards, and stay out of slam, even with sufficient ZAR points
2) assume system of biddign that can determine off two tricks in any one suit and stay out of slam even with sufficient ZAR points

Here are some hands from the first session. I looked at all the hands, but here are the 11 big hands, ZAR seems to work well on 9 and loses on two. The two bad ones are board 15 where ZAR evaluation would lead to slam that is down one (At least) for a loss of 216 imps. The second one is board 23 where ZAR points says bid game, which can be defeated. Several people made the game for a win of 191 iimps, but I went ahead and rated it down one, for a loss of 134 imps. The other hands bid game/slam by Zar points, gained 957 imps, for a net gain of 607 total imps. BTW, several of the other hands were in the slam zone (not shown below) but fall in the exlusions from #1 or #2 above. It will be interesting to check other hands from this event.

[quote]
2004 Cavendish  Invitational Pairs  1st Session
Board: 2        Dealer: E        Vul: N-S
                S  J 5 3
                H  A 10 9 6
                D  K 10 9
                C  Q 5 2
S  7 6                        S  K Q 10
H  Q J 7                      H  8 3 2
D  A J 8 6 5                  D  Q 7 3 2
C  9 7 4                      C  J 10 6
                S  A 9 8 4 2
                H  K 5 4
                D  4
                C  A K 8 3[/quote]

Ns 33 + 21 = 54, should be in 4[sp], which 45 imps making 4

[quote]==3===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 3        Dealer: S        Vul: E-W
                S  A J 7 6
                H  Q 6 5
                D  8 6 5
                C  8 3 2
S  2                          S  10 8 5
H  K J 9 7 2                  H  10 8 4
D  K 10                        D  A 9 7 4 3 2
C  K 10 7 6 4                  C  A
                S  K Q 9 4 3
                H  A 3
                D  Q J
                C  Q J 9 5[/quote]

NS 30 + 18 = 48 = 3[sp]
EW 26 + 29 = 55 = 4[he]

Bidding 4He wins 205 imps. IF NS take a 4SX sacrifice, wins 61 to 160 imps


[quote]==4===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 4        Dealer: W        Vul: Both
                S  9 6 4 3 2
                H  J 7
                D  6 5
                C  Q 7 6 4
S  A Q 7                      S  K J 5
H  A K 9 8 5                  H  6 4 3
D  A J 10 7                    D  Q 8 3 2
C  10                          C  A K 9
                S  10 8
                H  Q 10 2
                D  K 9 4
                C  J 8 5 3 2[/quote]

EW 40 + 24 = 66 = 6H, which makes, winning 76 imps

[quote]==6===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 6        Dealer: E        Vul: E-W
                S  A 10 9 3
                H  K Q 9 5
                D  J 7
                C  K 10 2
S  K Q 7 5 4                  S  J 8 6
H  A 3                        H  J 8 6
D  K 2                        D  10 9 8 4 3
C  Q 6 5 3                    C  9 4
                S  2
                H  10 7 4 2
                D  A Q 6 5
                C  A J 8 7[/quote]

NS has 28 + 29 = game in hearts. If they bid it, they win between 31 and 86 imps depending upon if they make an overtrick.


[quote]==12===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 12        Dealer: W        Vul: N-S
                S  -----
                H  K Q J 9 8 7 3
                D  Q
                C  J 9 7 6 5
S  A 10 8 4                    S  9 7 6 5 3 2
H  10 4                        H  A 6 5
D  A K J 10 7                  D  9 3 2
C  K Q                        C  4
                S  K Q J
                H  2
                D  8 6 5 4
                C  A 10 8 3 2[/quote]

EW 36 + 24 = 60 = stop short of slam. Win 40 imps if they let you play 4[sp]
NS do best by counting their points for clubs and taking 5[cl] sacrifice despite the vul. Turns out ok.


[quote]==15===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 15        Dealer: S        Vul: N-S
                S  Q 7 4
                H  7 2
                D  K Q 9
                C  A K Q 7 5
S  J 8 2                      S  6 3
H  A 3                        H  Q J 4
D  10 8 5 4                    D  A J 3 2
C  9 8 3 2                    C  J 10 6 4
                S  A K 10 9 5
                H  K 10 9 8 6 5
                D  7 6
                C  -----[/quote]

NS have values for slam in spades (South 17 distributional, 10 hcp, 4 control, plus two for top spades. North has 11 dist, 16 hcp, 1 for top spade, and 4 controls, for 65 points. On [di] lead and [he] switch, this is down two, but down one is more likely, and loses 216 imps.

[quote]==19===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 19        Dealer: S        Vul: E-W
                S  9
                H  Q 10 9 8
                D  9 8 6
                C  10 7 6 5 3
S  A K 4 3                    S  Q J 10 8 7 5
H  7 4                        H  A J 3 2
D  A J 10                      D  K 4 3
C  A K Q J                    C  -----
                S  6 2
                H  K 6 5
                D  Q 7 5 2
                C  9 8 4 2[/quote]

NS 40 40 = easy grand slam, win 106


[quote]==21===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 21        Dealer: N        Vul: N-S
                S  A K 10 4
                H  7
                D  A 10 6 5 2
                C  K 10 8
S  Q 9 8 7 3                  S  6 2
H  6 5 4                      H  A J 10 3 2
D  9 4                        D  Q J 8 3
C  Q 5 2                      C  A 6
                S  J 5
                H  K Q 9 8
                D  K 7
                C  J 9 7 4 3[/quote]

ZAR points bids 3NT NS, win 99 imps


[quote]==22===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 22        Dealer: E        Vul: E-W
                S  Q 9 5 4
                H  5 4
                D  10 9 7
                C  K 7 5 4
S  8 2                        S  K
H  6 3                        H  A K Q J 10 8 7
D  Q 6 5                      D  A K 8 4 3
C  Q J 9 8 3 2                C  -----
                S  A J 10 7 6 3
                H  9 2
                D  J 2
                C  A 10 6[/quote]

Zar points 63, says slam, win 139


[quote]==23===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 23        Dealer: S        Vul: Both
                S  Q J 8
                H  9 6 5
                D  Q 2
                C  Q J 10 5 2
S  10 9 3                      S  7
H  A 10 3 2                    H  K Q 7
D  6 5 4                      D  J 10 9 8 3
C  7 4 3                      C  A K 9 6
                S  A K 6 5 4 2
                H  J 8 4
                D  A K 7
                C  8[/quote]

34+18=52 = 4[sp] win 191, if it makes, lose 134 if down.

[quote]==27===============================================
2004 Cavendish  Invitational Pairs  1st Session
Board: 27        Dealer: S        Vul: None
                S  K 9 7 6 4 2
                H  A 7 6 5
                D  9 6
                C  9
S  A Q J                      S  10
H  9 2                        H  K 8 4 3
D  A 7 3                      D  K Q 8 5 4
C  A J 6 4 3                  C  K 10 7
                S  8 5 3
                H  Q J 10
                D  J 10 2
                C  Q 8 5 2[/quote]

33 + 26 +4 = 66 sounds like 6 minor, to protect [he]K, 6[di]. Lead would be [he]Q, so six [di] makes wins tons of imps (no one sniffed this risky slam), win something like 216 imps.
--Ben--

#2 User is offline   mikestar 

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Posted 2004-May-14, 11:21

I wouldn't charge board 15 against ZAR, at this level partnerships will have methods that can determine you are off two Aces even with a void.

For comparision, I evaluted these hands with my own 1-3-5 based method and it agreed with Zar on all hands except #3, where it indicates 3H for E-W.
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Posted 2004-May-14, 13:25

mikestar, on May 14 2004, 12:21 PM, said:

I wouldn't charge board 15 against ZAR, at this level partnerships will have methods that can determine you are off two Aces even with a void.

For comparision, I evaluted these hands with my own 1-3-5 based method and it agreed with Zar on all hands except #3, where it indicates 3H for E-W.

Whoops, right you are.. manual defect, I didn't notice it was off two aces, my bad. This would cleary fall under my exception to following ZAR point count for slam bidding. So this would save 216 IMPS, so ZAR on first session "swing hands" would improve from a net +607 to a net + 823. Quite an impressive performance when you consider this is now only over the 10 criticial hands.

Of course one trick is estimating your total ZAR point count when you can't see all the cards, but that isn't taken into account in any of this analysis.

As far as agreeing with ZAR evalution, Mike, your also says 4 on hand 23? About a third declearer's made it, but clearly it is "easily" (relatively of course) defeated?

ben
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Posted 2004-May-14, 15:00

mikestar, on May 14 2004, 12:21 PM, said:

For comparision, I evaluted these hands with my own 1-3-5 based method and it agreed with Zar on all hands except #3, where it indicates 3H for E-W.

I was just running a comparison too.

On #3 I'd count 4 as a minus for Zar. I wouldn't want to bid 4 looking just at the EW cards.

On #23 game is close under my method of calculation. A total of 25.5 points. Worth it to stretch to game. Evolved Binky predicts 9.82 tricks.
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Posted 2004-May-14, 15:54

inquiry, on May 14 2004, 07:25 PM, said:

As far as agreeing with ZAR evalution, Mike, your also says 4 on hand 23? About a third declearer's made it, but clearly it is "easily" (relatively of course) defeated?


This hand is (for my methods and probably for Zar's) comparable to the slam exceptions--the point count says bid it but you'll stay out at the table, if you have good methods.

I rate South as a good game try and North as a borderline acceptance. After 1S-2S South will bid 3C if playing short-suit game tries or 3H if playing help-suit game tries, and in either case North stops at 3S.
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Posted 2004-May-14, 20:59

tysen2k, on May 14 2004, 04:00 PM, said:

mikestar, on May 14 2004, 12:21 PM, said:

For comparision, I evaluted these hands with my own 1-3-5 based method and it agreed with Zar on all hands except #3, where it indicates 3H for E-W.

I was just running a comparison too.

On #3 I'd count 4 as a minus for Zar. I wouldn't want to bid 4 looking just at the EW cards.

On #23 game is close under my method of calculation. A total of 25.5 points. Worth it to stretch to game. Evolved Binky predicts 9.82 tricks.

Well... want to be in, not want to be in, is not the exercise. The exercise I choose to investigate is the hand from the cavendish related to ZAR evaluation. I make no judgement as to whether or not it is a good contract that unluckily goes down or a horrible contract that luckily is unbreakable. I simply use double-dummy solving software and see if the contract would, or would not make. True I do sometimes perform a practical evalution as well.

The advantage of ZAR evalation, is his page explains easily how to calculate ZAR points, anyone can do it, no calculator needed. The hands are there for anyone to look at. The criteria for game and slam based upon points are laid out. I added the not off two quick tricks in one suit or two aces as a rule to ignoring the ZAR point count and stay out of such slams.

So far, ZAR points are holding up very well on the big swing hands. They do alright on the lower hands as well, but I am dealing with games and slams for my evaluation.

Ben
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Posted 2004-May-15, 06:20

I'm not sure what the results mean, its ovious any system evaluation which doesnt have to find bids will do better then real biddings.
I think only comaring with other systems will tell us how good zar did.
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Posted 2004-May-15, 06:57

Flame, on May 15 2004, 07:20 AM, said:

I'm not sure what the results mean, its ovious any system evaluation which doesnt have to find bids will do better then real biddings.
I think only comaring with other systems will tell us how good zar did.

Hi,

A month ago, I raised the question in another thread, entitled, Zar points, useful or waste of energy, New to the concept, does it help... . I raised this question a few days after my partner, MishoVnBg, pointed out Zar's webpage and I went and read it.

What I discovered on Zar's page, was a theoretical and mathematical explaination that suggested the apporach I had taken for my own "light opening" bids was sound. In otherwords, Zar was advocting opening hands with less (sometimes well less than 11 hcp) that matched what I was doing at the table (and sometimes opening even lighter hands that I traditionally did). Playing with Misho, for instance, we long ago left behind the rule or 20 for opening bids.

Since that time I have been looking at hands in my own records where I failed to bid game or slam and doing ZAR math. Almost without exception ZAR points indicated game/slam should have been bid. So I decided to see how this works in some event with lots of boards, high stakes, good players: cavendish fits the bill.

The system comments are well taken. There is no way that I can see to determine if you have exaclty 52 ZAR points, or only 51 for instance unless you can see both hands. But I am not cheking systems here, I am not evaluating if it is a lucky game (like #3) that happens to make as "bad for Zar" or an unlucky one that goes down due to hrorible splits (like 5-0 trumps AND two hooks offside) as "good for ZAR". IF it goes down in this event it is bad, if it makes it is good. In the long run such "luck" (good and bod) will average out. No one slse needs to participate, but I like Mikestar's contribution, he even posted his evaluation method, that can be used side-by-side. I guess we could have thrown in standard evalation to see what it says. What is being tested here is "counting points" is this hand worth game or slam.

ben
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Posted 2004-May-15, 10:34

Ben this is good, but i think in order to get a feel for how good it function you need to comare it with another evaluation system even a simple one.
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Posted 2004-May-15, 10:41

I think that there is a major flaw with the analysis that is being done here:

As people know, I am a major fan of light opening system. With this said and done, you can't just look at a bunch of big hands from a major tournament and use this to conclude whether Light Openings work or not.

Light opening structures place significant amounts of stress on other parts of the system. As an example, MOSCITO requires a strong club opening and extensive use of relays. Ben and Misho have had to adopt a highly artifical 21/1 response structure. I would argue that there major suit openings have too wide a range for accurate competitive bidding (however, thats another story)

You always need to analyze the costs along with the benefits...
Sadly, I've never seen any good studies that have been able to apply formal methodologies to bridge...
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Posted 2004-May-15, 14:12

hrothgar, on May 15 2004, 11:41 AM, said:

I think that there is a major flaw with the analysis that is being done here:

As people know, I am a major fan of light opening system. With this said and done, you can't just look at a bunch of big hands from a major tournament and use this to conclude whether Light Openings work or not.

Light opening structures place significant amounts of stress on other parts of the system. As an example, MOSCITO requires a strong club opening and extensive use of relays. Ben and Misho have had to adopt a highly artifical 21/1 response structure. I would argue that there major suit openings have too wide a range for accurate competitive bidding (however, thats another story)

You always need to analyze the costs along with the benefits...
Sadly, I've never seen any good studies that have been able to apply formal methodologies to bridge...

hmmmm...

First, this thread is NOT about light opening bids, or any opening bids. It is about how well Zar point/evaluation works on the Cavendish hands. So the rant here seems odd (yes, i did refer to light opening bids, in why I got interested in Zar theories.

As far as misho's and my range of 1M, it is probably not as wide as you may think. For we incorporate acol 2 bids in a major into our 2 opening bid, and big balanced hands with only five card major into our multi-2. I am very happy with our opening 1M range.
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Posted 2004-May-17, 11:23

inquiry, on May 15 2004, 07:57 AM, said:

Since that time I have been looking at hands in my own records where I failed to bid game or slam and doing ZAR math. Almost without exception ZAR points indicated game/slam should have been bid.

Problem is if you don't look at every single hand (even the uninteresting ones) you don't capture the whole problem. Zar's main weakness is not in the missing of games or slams. It's weakness is when only a boring partscore can be made but Zar tells you to bid game. By only looking at the hands where game can be made, you are ignoring this aspect.

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Posted 2004-May-17, 11:59

tysen2k, on May 17 2004, 05:23 PM, said:

inquiry, on May 15 2004, 07:57 AM, said:

Since that time I have been looking at hands in my own records where I failed to bid game or slam and doing ZAR math. Almost without exception ZAR points indicated game/slam should have been bid.

Problem is if you don't look at every single hand (even the uninteresting ones) you don't capture the whole problem. Zar's main weakness is not in the missing of games or slams. It's weakness is when only a boring partscore can be made but Zar tells you to bid game. By only looking at the hands where game can be made, you are ignoring this aspect.

Tysen

Having experimented with Zar points, I think that this problem can be overcome if responder assumes at the outset that there is no good fit, and subtracts 3 or so Zar points when choosing his bids. If the bidding confirms a fit, then he can add those points back and use the full Zar score.

So although 26 Zar points is theoretically enough for game opposite an opening bid, I would only force to game with 29 or 30, unless I had a fit for openers suit.

Obviously, this has only been tested on a relatively small sample of hands, so it should be treated with suspicion initially.

Eric
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Posted 2004-May-17, 12:53

tysen2k, on May 17 2004, 12:23 PM, said:

inquiry, on May 15 2004, 07:57 AM, said:

Since that time I have been looking at hands in my own records where I failed to bid game or slam and doing ZAR math. Almost without exception ZAR points indicated game/slam should have been bid.

Problem is if you don't look at every single hand (even the uninteresting ones) you don't capture the whole problem. Zar's main weakness is not in the missing of games or slams. It's weakness is when only a boring partscore can be made but Zar tells you to bid game. By only looking at the hands where game can be made, you are ignoring this aspect.

Tysen

Hmmm.

In fact, I do look at EVERY hand from cavendish, or how else can I find the interesting one? But I am not about to clutter up the forum with a hand every single pair bid game on, or a hand that was played at the two level one way or the other, or in 1NT or passed out. By stating these are the ones I hold up to examine (good or bad), it challenges others to show hands where ZAR is horribly wrong if they like. For instance, in your first reply, you claimed you were going to count ZAR wrong on board #3, because you considered it a bad contract. Well, I count it right becasue the contract makes, and if there is 95% ZAR contract that goes down, I will count it wrong. I am not getting involved in evalauting the quality of contract per se (40%, 50%, 70%), but rather or not it would have made in the contest. That way, I don't influence the results by picking which ones are good or bad. Overtime,most of the bad ones will go down, most of the good ones will make, just like in the real world. I wonder if you apply such self-fulling evauation methods to the hands you analyzed in your evalation methods?

I also have to wonder, why you would care one way or another (at least enough to tell me how wrong I am) for my evalution of my own hand record? I have way too many hand (20 log books of interesting hands BEFORE I Stated saving hands from on-line games), to manually go back over all of them by any form of analysis (ZAR or otherwise). I decided to use on my hands as a test of ZAR thingee, to see how well ZAR evaluation would have been in suggesting bidding more. There can be no wrong approach in that TASK, becasue I framed the very simple question to apply myself. Would ZAR evalaution have helped me reach these contracts (of course, if I could have accurately evalutated the combined ZAR points). In fact, for the question I posed, the approach I took was entirely accurate.

Now, for as far as Cavendish hands, in fact, I am evalauting all hands where ZAR points say bid on (your "overbid to game" when you have only a part-score hand, which is in fact, not something I am doing on my own hand record) that don't work. Any hand with 52 zar points and a major fit or 57 zar points and a minor fit I will assume game is reached. This is EXACTLY the condition you discuss (bidding on to game when ZAR points tell you too, when you only have a part-score). The Cavendish hand record is available for anyone who wants to give their favorite hand evaluation tool a whirl. This includes not only the ones I posted so far (or the future ones I will post), but ones I skip as well. If you want to make it a comparative evaluation contest, which I have no interest in doing as I am still testing the usefulness of Zar evalation, feel free to do so. How to calculate ZAR points is extensively published. I use the minus points system first suggested by Eric for one partner being short in trumps, and then all the other normal ZAR points and ZAR fitting points as published on Zar's webpage. So you can flag one or two hands where ZAR fails miserably, and your favorite tool wins. But be sure to spell out how your evalation works, so others can test hands where ZAR's method works and yours fails.

BTW, I suspect ZAR will beat me to publishing all the cavendish hands with ZAR point analysis. I am a bit slow determining what can make. There is an interesting 7 contract in the second or third section that on one bid (KQ doubleton opposite AJT9x). The points are there for grand slam. There is a 9 card club fit, and a seven card spade fit, with more than 67 ZAR points and no quick loser. Interestingly 7 is down, but 7 makes, and i think (I will need to rechecked it), ZAR points for the 5-2 spade fit was one point higher than for the 7-2 club fit, suggesting 7 should be the contract (despite subtaction for two spades). No way to bid 7, of course.

In conclusion, for the fourth time, what I am testing using the cavendish pairs event as the data set, is the premise that 52 ZAR points you should bid major game if you ahve fit, with 57 Zar points you should bid minor suit game if you have a fit, with 62 points you should bid slam in your fit (if not off two quick tricks), and with 67 points you should bid grand slam (if not off one quick trick). Since I SET UP what I WANTED TO EVALUATE, I choose to ignore partscore hands (although any 52 Zar point that game goes down so you should have been in part-score clearly isn't ignored, and any game that makes with less than 52 ZAR points or slam iwth less than 62 will not be ignored either). If that bothers anyone, YOU evalaute any of the hands you like using ZAR or anyother system you want, but stop telling me I have to evaluate the hands in some manner you want them evaluated in. From this standpoint, I think Mikestar has the right idea. I am know using the method he published here to compare the evaluation to ZAR, and I think he might share with us the result of his evalution.

Ben
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#15 User is offline   tysen2k 

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Posted 2004-May-17, 16:38

No need to get defensive. I'm just trying to help everyone out and make sure we all use good practices when evaluating anything. I can't help it, it's part of my job. :)
A bit of blatant self-pimping - I've got a new poker book that's getting good reviews.
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#16 User is offline   Zar 

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Posted 2004-May-17, 21:11

Hi, guys:

Just came back from a contract in Europe and find the time to start going through the threads. A quick preliminary remark:

*** tysen2 wrote : "Zar's main weakness is not in the missing of games or slams. It's weakness is when only a boring partscore can be made but Zar tells you to bid game. "

I laughed a lot! Wholeheartedly! :-) I mentioned several times that nobody notices the real beauty of Zar Points, which is the NOT-OVERBIDIING capability, demonstrated in the tens of thousands of boards which you can download from
the website.

You can also read the "How Aggressive should the Aggression be" in the Japan Bridge here:

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

if you don't have the time to read the through the research-records or to make your own research.

Iíll go through all the threads in the next day or so and Iíll address the questions, but in the mean time you may read the results from the several experiments I briefed in the thread ďZar points, useful or waste of energy".


Make it a great day:

ZAR
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#17 User is offline   lexica 

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Posted 2004-May-18, 07:23

Hi, Zar et al. :)
The link you gave shows something else; your article is in on of the bulletins (scroll down a bit guys).

http://www.jcbl.or.j...letins/blt5.pdf

Don't forget to have a great day!

Elena
What do I know of man's destiny? I could tell you more about radishes. -Samuel Beckett
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Posted 2004-May-18, 07:51

lexica, on May 18 2004, 08:23 AM, said:

Hi, Zar et al. :)
The link you gave shows something else; your article is in on of the bulletins (scroll down a bit guys).

http://www.jcbl.or.j...letins/blt5.pdf

Don't forget to have a great day!

Elena

Hi Elena

If I remember correctly, Zar has an article in each of the bullentin (you linked number 5). People can change the "5" to 1, 2, 3, 4, 6 and 7 to read the other Zar articles. Each makes an interesting point, the last two (issues 6 & 7) are nice ones, and short, dealing with one hand each. Of course, you have to have read something about ZAR points on earlier ones in this series (or his webpage) to follow those.

Ben
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Posted 2004-May-26, 21:14

Quote

==1===============================================
2004 Cavendish   Invitational Pairs   2nd Session
Board: 1         Dealer: N         Vul: None
                S  A J 5 2
                H  A 5 4 3
                D  K 6
                C  K 6 4
S  Q 10 9 7 3                  S  K 8 4
H  Q J 8 7 2                   H  10
D  Q 9                         D  J 10 8 4 2
C  J                           C  10 9 7 3
                S  6
                H  K 9 6
                D  A 7 5 3
                C  A Q 8 5 2


My initial post in this thread showed too many hands to generate any real disucssion of the merit, or yes, lack of merit of ZAR points. So for the second session post, I thought we would go one or two hands at a time.

This is the first hand of the second session. Below you can see the frequency of resulst on this hand, the field played in 3NT.

570    1    123    8
430    11    29    110
400    11    6    121
-100    1    -252    14
-150    1    -256    14
            267

What does ZAR say. First Count NS Zar points. For this, hc = high card points, cp = control points (A=2, K = 1), DP = distributional points ((long suit -+ second longest suit) + (long suit - shortest suit), and SC = stregth concentration, defined as 11-14 hcp in two suits (and this most all points), or 15+ in three suits.

Initially on this hand,
North: 15 HC, 6CP, 10 DP = 31 Zar pts
South: 13 HC, 5CP, 13 DP, 1 SC = 32 Zar pts

North open 1NT, and South shows clubs, so NS-find fit. Once club fit is discovered, North gets plus one for K. For 64 points. ZAR says 62 needed for slam. This is a great slam, however the easy line to make it fails due to the 4-1 trump slit. However, it is possible to elope with 12 tricks. Win lead in dummy. Cash A, ruff , K, ruff , A, K, lead low . It does east no good to ruff, so he pitches a diamond, win K, ruff , lead a . If east ruffs, discard. The field played 3NT, so we had to calculate what 6 would be, it turns out a win of 267 imps.

Ok. I am sure plenty of people will say how expert judgement and card placement they would reach this siam without ZAR points. I will just not in a field of all experts with huge money prize, 6 was not a favorite contact.

Quote

==2===============================================
2004 Cavendish   Invitational Pairs   2nd Session
Board: 2         Dealer: E         Vul: N-S
                S  Q
                H  Q J 9 8
                D  10 8 5 3
                C  A 7 4 2
S  8 7 6                       S  A 9 4 2
H  K 2                         H  10 7 5 3
D  Q J 7                       D  A 6 4
C  K Q J 10 3                  C  8 6
                S  K J 10 5 3
                H  A 6 4
                D  K 9 2
                C  9 5


South: 11 HC, 4 CP, 11 DP = 26, will open 1
North: 8 HC, 2 CP, 11 DP = 22, gets one more for Q

South easily opens 1 by ZAR. West might venture 2 b
But lack of fit is a slow down warning. South open 1, west bid 2, north gets a bonus point now for the Q and will make a negative double. South rebid 2 perhaps (or 2), either which should become the final contact... south because with a bare opener, he will not want to encourage, and north because the misfit is a slow down signal and because after south's minimum rebid, he knows there isn;'t enough ZAR points for game. Either contract looks to win at least 8 tricks, so letís call it +110 and 64 imps.

N-S    IMPs    Pairs
-90    -59    1
-100    -60    2
-120    -78    2
-200    -119    4
-300    -175    1
50    26    4
90    52    1
100    63    3
110    64    1
140    87    4
170    105    1
200    124    1

AFter two hands of the second session, ZAR poiints have held up well. Of course, this hand two is the type I ddint' show for the first session, because it is boring. This time, we will try to plug through the hands in order, boring or no. On thing for sure, ZAR pts are off to a fast start in the section session.

Ben
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Posted 2004-May-28, 09:56

Ok, let us leave the world of ZAR/Cavendish where all four hands are shown, and try something different. Imagine this is your south hand..... and you hear....

Playing with a sound, and reasonable partner (2 normal weak two) you hear:
Dealer: North
Vul: NS
Scoring: IMP
AKJ75
K76
973
Q5
West North East South
 -     2    Dbl

Over the double, do you

1) Leap to game in
2) Make a redouble
3) Bid 2NT
4) Bid 3
5) Pass calmly and wait development
6) Other
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