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What are the odds?

#1 User is offline   jtfanclub 

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Posted 2007-June-28, 19:44

Playing Precision in the ACBL tournament.

I open 1 club, next player bids 1 spade, two passes, I X, partner converts. Down two, doubled & vulnerable.

Three boards later, Partner opens 1 club, next player bids 1 spade, two passes, partner X's, I convert. Down two, doubled & vulnerable.

And to top it off, both scored 89.2%!

What are the odds of that?
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#2 User is offline   mycroft 

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Posted 2007-June-29, 10:06

Neat.

My favourite interference to 1C auction: Last board of the Swiss. Winner places somewhere between 3rd and 6th, depending on the size of the win. We feel we're slightly ahead.

1C-X (two places to play)-P (0-4 or penalty)-P-P. +240 on the 3-3 fit was the difference between 4th and 6th.

Michael.
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#3 User is offline   gwnn 

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Posted 2007-June-29, 10:47

This one happens to me all the time

I make a silly discard when opps are in 3NT, which should just make. -490 and 0%

Then on a very closely following deal opps are in 3NT i make a silly discard and turn -400 into -490. 0%

Eerie!
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#4 User is offline   kenrexford 

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Posted 2007-June-29, 11:04

I had two hands in a row that had five diamonds, a five-card major, and slam interest (five losers).

Both time, I opened the major, heard a jump to 4 from LHO, partner doubled, and RHO bid 5.

One time, doubling crushed the opponents and biddign left us down. One time, the double of the opponents leads to a making contract but we have a slam that makes.

The honor cards in my hand, both time, were the same.

This was not all that remarkable, though, as someone at that local club sets up tricky hands for us "without us knowing." That person wins a lot.
"Gibberish in, gibberish out. A trial judge, three sets of lawyers, and now three appellate judges cannot agree on what this law means. And we ask police officers, prosecutors, defense lawyers, and citizens to enforce or abide by it? The legislature continues to write unreadable statutes. Gibberish should not be enforced as law."

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#5 User is offline   foo 

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Posted 2007-June-29, 12:22

kenrexford, on Jun 29 2007, 12:04 PM, said:

This was not all that remarkable, though, as someone at that local club sets up tricky hands for us "without us knowing." That person wins a lot.

That person should either not be allowed to play the boards they made or not be allowed to play Bridge due to being "ethically challenged". Their choice.
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#6 User is offline   kenrexford 

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Posted 2007-June-29, 16:45

foo, on Jun 29 2007, 01:22 PM, said:

kenrexford, on Jun 29 2007, 12:04 PM, said:

This was not all that remarkable, though, as someone at that local club sets up tricky hands for us "without us knowing."  That person wins a lot.

That person should either not be allowed to play the boards they made or not be allowed to play Bridge due to being "ethically challenged". Their choice.

Yeah, actually by "a lot" I mean "a lot for them."

At one point, I found this outrageous and reported it to the ACBL, who of course did nothing. Then, I realized that "stacked hands" could be fun. We started winning because I could figure out the trick early enough. The most fun was getting four tops (small game) against the culprit. LOL
"Gibberish in, gibberish out. A trial judge, three sets of lawyers, and now three appellate judges cannot agree on what this law means. And we ask police officers, prosecutors, defense lawyers, and citizens to enforce or abide by it? The legislature continues to write unreadable statutes. Gibberish should not be enforced as law."

-P.J. Painter.
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#7 User is offline   foo 

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Posted 2007-June-30, 18:20

kenrexford, on Jun 29 2007, 05:45 PM, said:

foo, on Jun 29 2007, 01:22 PM, said:

kenrexford, on Jun 29 2007, 12:04 PM, said:

This was not all that remarkable, though, as someone at that local club sets up tricky hands for us "without us knowing."  That person wins a lot.

That person should either not be allowed to play the boards they made or not be allowed to play Bridge due to being "ethically challenged". Their choice.

Yeah, actually by "a lot" I mean "a lot for them."

At one point, I found this outrageous and reported it to the ACBL, who of course did nothing. Then, I realized that "stacked hands" could be fun. We started winning because I could figure out the trick early enough. The most fun was getting four tops (small game) against the culprit. LOL

Nicely Done B)

Reminds me of a time I caught a pair cheating against me by using Cadence Count. I started using their Cadence Count to improve my declarer play :P
They were !not! happy...

Or the pair I played against who kept telling me "We have no agreement" or "Undiscussed" or some other vague answer whenever I asked them about a bid or sequence. These two had been playing together as a pair for 30+ years. :rolleyes:
So I
a= informed the lead official in private (with documentation as to boards), and
b= started nailing them that they could not make certain bids or decisions in particular auctions because w/o discussion or agreement, their preferred choice was not a Logical Alternative! :lol:
They of course called the cops. The lead official came over, asked if the facts as to the prior statements by them were accurate, and then ruled that since that had established the precedent, I was 100% correct :P
Then he told them "You are obligated to have agreements. You are obligated to share them. I am !not! obligated to let you play in any tournament where I am an official if this happens again."
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#8 User is offline   jdonn 

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Posted 2007-June-30, 19:19

I once on consecutive hands opened 2 with 5-5 in hearts and diamonds, and had my opponents bids to 5 on both.
Please let me know about any questions or interest or bug reports about GIB.
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#9 User is offline   helene_t 

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Posted 2007-July-01, 03:52

Suppose that there are 500 different auctions that all are equally likely to come up. Of course there are more than 500 but on the other hand, some are more frequent than others.

Then the odds of the same auction comming up twice in a (say) 24 board event is approximately 24*23*0.5/500 ~ 55%. This number may be contra-intuitive. Like the surprisinglingly high chance that two persons at the same party have the same birthday. (To be fair, it would be less spectacular if the auction was a mundaine 1N-3N so maybe this number of 500 should be chosen somewhat higher for the purpose of this thread).

Adding the criteria that the vulnerability of opps must be the same halves this (not quite since some auctions are more likely at some vulnerabilities than others). So we're down at 28%. It is not so rare that those two identical auctions also lead to the same result. Let's say we're now at 11% or some such.

What the odds that the matchpoints score is the same? If there are, say, 11 other tables, there could be as much as 23 possible scores so the chance of the two results giving the same matchpoints would be 1/23. Now there are usually less than 23 different scores because of ties, and besides some results are more likely to give good MPs than others. Maybe there were much more than 12 tables. Let's set the chance to 1/10. Now we're at 1%.

Maybe more realistic parameter choices would give a somewhat smaller number. 0.1% would not surprise me too much. But in general, miracolous thing happen more often than they should according to most people's intuiition for probabilities. The myth that something terrible happens when you see a black cat cross the road from the left side at full moon, or that people born in the month of the Weight tend to be balanced personalities, probably origin from someone noticing such coincidences and then wrongly jumped to the conclusion that it could not be mere coincidence.

1% (or 0.1% or whatever it is) may sound as small numbers, but if 100 BBF regulars each play 50 of such events each year, such coincindences will happen to one of us 1% * 50 * 100 = 50 times a year. And then we're only considering the specific type of coincidence where the same auction by the same pair during the same event at the same vlnerability leads to the same score and the same matchpoints. Factor in the opening lead, or compare what happened to one pair to what happened to another, or compare two events, or maybe even factor in the shape of the opponent's glasses, or the questions they asked during the auction. There are millions of kinds of coincidences that might have happened, and hundreds of them happen to each of us every day. Of course the really crucial filter is coincidences getting noticed and reported.
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#10 User is offline   kenrexford 

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Posted 2007-July-01, 06:32

Actually, what I find to be the most amazing statistic, although I do not have a ratio or percentage or number that I know -- just a general statistic, is the wild variety of end contracts (forget results) one section of bridge players can reach on each board, with the exact same cards.
"Gibberish in, gibberish out. A trial judge, three sets of lawyers, and now three appellate judges cannot agree on what this law means. And we ask police officers, prosecutors, defense lawyers, and citizens to enforce or abide by it? The legislature continues to write unreadable statutes. Gibberish should not be enforced as law."

-P.J. Painter.
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