In a message dated 7/11/01 6:32:14 AM Eastern Daylight Time, [EMAIL PROTECTED] 
writes:

<< 
 That's the biggest trouble with statistics. If chances for some kind of 
damage
 are just low enough it all sounds just fine untill it hits you personally. 
Like
 a 1 in 2000 chance for spina bifida doesn't sound like too much. But so does 
a 1
 in a 100million chance to win the lottery. Then again neither the one nor the
 other has kept people from taking those chances for better or for worse. :o/
  >>
One of the most difficult notions to accept about statistics is the 
inevitability of rare events if the sample is large enough. If the risk of 
cancer of a specific type is 1 in 10,000 then one should expect and not be 
surprised if 100 people out of 1,000,000 get this cancer (if more or less got 
the disease then the statistic would change). Now this seems obvious but we 
humans are good at estimating risk. 1 in 10,000 translates into "never" using 
intuitive reasoning but this is wrong. As per your lottery example, the 
chance of winning is essentially nil but the chance of there being a winner 
is essentially 100% (sort of like the old Myron Cohen punchline -"Everyone's 
got to be someplace").  Daniel Dennet has a fine example of the how difficult 
it is for individuals to think about uncommon occurences in large samples. 
What is the incidence of a team winning 8 straight games in a 256 team 
elimination tournament? 

The incidence is 100% since the winner of the tournament must win games in 
all 8 rounds. (Another trick that uses the same sort of logic although 
slightly off topic {Pick any number of teams in a elimination tournament 16, 
56, 1775377, etc. How many games in the tournament - answer respectively 15, 
55 1775376 - How to figure it out - Each team in the tournament loses one 
game except the winner who loses no games. Total loses = total games).

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