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Considerations on par

#1 User is offline   cencio 

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Posted 2024-May-10, 14:13

I thought playing the par was the best result.
Instead playing in tournament, I saw that playing the par often gives a bad result on the contrary opponents who do not achieve the par often have a good result
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#2 User is offline   smerriman 

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Posted 2024-May-10, 14:31

Par is theoretical only; there are hands where par is not achievable without ludicrous bidding, let alone the fact it requires perfect opponents, and perfect double dummy play and defense. Like looking at the double dummy scores for a particular contract, it can provide some useful information if used in conjunction with analysing the hand manually, but doesn't have any real life relevance solely by itself.
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#3 User is offline   mycroft 

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Posted 2024-May-10, 14:57

An example from yesterday:



Never mind the auction (It'll never happen, but let's assume something like strong club - 1 showing spades; 2-3; 3-4?) How do you beat this contract?

There's only one way. Use the GIB button to see it if, after a few minutes, you can't spot it directly.

Now, anybody that finds this (or the same defence in 3 by W, leading to the par score of N/S -140) will be in front of the club's ethics committee next week.

The key is that "par" is the best result possible when all the cards are face up and everyone bids and plays perfectly, knowing the layout. That's not how bridge is played.

"Beating par" isn't something you should be trying to do. It is, as smerriman says, a nice first step to finding out what should happen at the table. But you have to then look at the hand and see if it's reasonable when you can't see all 52 cards.

Spoiler

When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)
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#4 User is offline   P_Marlowe 

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Posted 2024-May-11, 01:58

In an uncontested auction, if your side has the majority and goes plus, try to achieve the par result,
and if you have it, try to induce errors.

But again, droping the Doubleton Offside Queen without add. info is not the way to do it.

Par will quite often say slam makes, when the real / practical par is game (maybe with 1 or 2 overtricks).
With kind regards
Uwe Gebhardt (P_Marlowe)
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#5 User is offline   cencio 

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Posted 2024-May-11, 04:50

I often do free tournaments with robots.
And I analyze the hands I played.
Sometimes I play the par and I take a 38%. Times the opponents have the par at 3 nt, I realize 2 hearts. and I take a low percentage.
All this appears strange to me and makes me understand that even in bridge, the fortune component, linked to the resulting of the other tables, is not a little thing
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#6 User is offline   DavidKok 

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Posted 2024-May-11, 05:37

I think you'd do well to reread some of the other responses. The suggestion that the par score should have a strong predictive value for how well you do on a board is flawed, and attributing the difference to a 'fortune component' is mistaken.
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#7 User is offline   mycroft 

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Posted 2024-May-12, 10:29

View PostP_Marlowe, on 2024-May-11, 01:58, said:

Par will quite often say slam makes, when the real / practical par is game (maybe with 1 or 2 overtricks).
Par will quite often say that the best score is 7 doubled off 4 or 5 (because slam makes), when the real/practical median result is game (maybe with 1 or two overtricks).

More relevant to "don't try to make par", frequently par is 3mx-1 for 100 beating 2M= for 110. Always doubling the opponents when they go past your makeable result is a recipe for failure, especially at IMP scoring; taking your "below par" 50, avoiding the times you guess wrong and give up 470... (but also read up on "the matchpoint double" when they're vulnerable)
When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)
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#8 User is offline   Douglas43 

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Posted 2024-May-15, 02:37

Great example by Mycroft.
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#9 User is offline   thepossum 

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Posted 2024-May-20, 10:52

Thinking along golf lines par means what a reasonable professional result is most of the time. Not hole in one

EDIT on a professional level course lol
I've played some public golf holes that were easy even for me on a good day
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#10 User is offline   mycroft 

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Posted 2024-May-20, 13:21

Most of the time, par approximates a "reasonable professional result", yes.

But it by no means *is* a "reasonable professional result". Frequently (as in, 3-5 boards a session), it is either:
  • "of course you'll double the partscore when they can set you" (even if it's 50 into 100 that is a near-zero swing, risking 110 into 470 if you're wrong. More reasonably, it's 200 that beats 140 if you go on, because of course you know *that's* happening);
  • "nobody's going to get there, but it makes" slam
  • the "7-level save" (esp. vul vs not) I mentioned above against the "nobody's going to get there, but it makes" slam (but scores very badly against the 680s that *actually* happen);
  • hands like the one I posted above, where "it makes/goes down, but only on a line nobody will find in real life without help".

That last one, in particular, has a strong secondary point at matchpoints, with "but we beat par, why are we average?" even in situations where "line that needs help" is just the overtrick (and you're -420 with everyone else, looking at par -450).

As I said, it's a good first approximation. But in order to use it effectively, you have to be able to look at the hands to see how off that approximation would be single-dummy, and which way. Which is the warning we're trying to give the OP.

A good (but probably useless for the audience) analogy is the difference between an experienced carnival punter playing a new whack-a-mole like, and a speedrunner who has reverse engineered all the patterns. Sometimes skill will approximate knowledge; sometimes, it will be way off, even if it's the best "skillful" result.
When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)
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#11 User is offline   thepossum 

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Posted 2024-May-20, 14:12

I've seen par used to allow for a perfectly manipulated auction too lol

You could have done better to push them to an umakeable contract and then double

That to me sounds sub par
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#12 User is offline   mycroft 

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Posted 2024-May-22, 18:01

An example of the "7-level save", from yesterday:

Par contract. Never mind the auction, it will be competitive no matter what people do.


If you don't beat par as N-S, you're either incredibly unlucky or your opponents have a wire.

If you do get par as N-S, I expect a round zero in a large field. Okay, some nutter will push them to 6, double, and give away the (DD) overtrick for -1190. So maybe a square zero.

We didn't have a large field, but the bottom scores N-S were one -500 in 5x-3, and two -420s in 5+1. I could see some getting -920 or -800, but expect -420 to be average minus.

But we beat Par! How unfair!
When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)
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#13 User is offline   pescetom 

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Posted 2024-May-23, 04:12

Let me guess: South passed this aceless and awkwardly shaped hand planning to come in later, hopefully after partner shows spades :)
More seriously, it looks to me as if EW have some chance of finding 6 even without being pushed.
Not that that will often happen or invalidates your point, of course.
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#14 User is offline   mycroft 

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Posted 2024-May-23, 09:15

Our auction:


No idea what the other tables' were.

Just because I can see the merit in some conservative actions doesn't mean I am one :-).
When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)
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