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What is the probability of...

jaldaen

First Post
a single person being an eyewitness to freakish accidents on six consecutive Friday the Thirteenths. I am assuming it is low, but I just wanted to find out the actual odds of this happening.
 

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It is not possible to calculate odds of subjective results. How frequent are "freakish" accidents as opposed to normal accidents?
 

It is not possible to calculate odds of subjective results. How frequent are "freakish" accidents as opposed to normal accidents?

Good point... how about what's the odds of being stuck by lightning (1/400,000) on six consecutive Friday the 13ths (6 days within an approximately 880 day span).

What about just being in a fire (1/300) on six consecutive Friday the 13ths (6 days within an approximately 880 day span).
 
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Okay, I think the "six consecutive Friday the 13ths" portion of this is a red herring, and doesn't change the probability. Unless you are superstitious, or the events in question have notable dependency on human calendars (like, one is more likely to be injured by fireworks on the 4th of July), the date is immaterial. As a way to prove this, remember that the choice of calendar is arbitrary - You could look at those dates through an Aztec calendar, where there is no "Friday the 13th" at all...

Pick any six specific days at random from the same span, and the answer should be the same.
 
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To answer your question, I believe it would be (probability of such an event happening once)^6.

Assuming that the event is independent of itself (ie, one instance of the event doesn't change to likelihood of another instance of the event).
 

To answer your question, I believe it would be (probability of such an event happening once)^6.

Assuming that the event is independent of itself (ie, one instance of the event doesn't change to likelihood of another instance of the event).

Except that these are quite definitely not independent events. The chance of getting hit by lightning once may be 1/400,000, but the chance of getting hit by lightning twice is less than 1/400,000^2 because that first time might have killed you. Unless you are counting the chance that your corpse gets hit by lightning.

On a highly related note, what's the chance that you drowned on six Friday the 13th's in a row? If you answered 0, you're right!

Not to mention the fact that you may have died between the two dates in question... Perhaps by spontaneous combustion or asteroid.
 

To answer your question, I believe it would be (probability of such an event happening once)^6.

Assuming that the event is independent of itself (ie, one instance of the event doesn't change to likelihood of another instance of the event).
QFT. An amazingly minuscule percentage.
 

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