/sci/ - Science & Math

>>7042319
>i understand the math
>but there's no way this is possible
One of these statements is false.

>>7042334
>i understand the proof but the proof must be wrong

happy?

If you had to guess the "right" answer, what would it be?
This you helps see why you don't trust the answer.
Try to think about why your guess isn't right.
If you need help, post your guess.

Im probably wrong but isnt it just 2/23 * 365?
Seems like bullshit internet hownelly

>>7042352
Just look on wikipedia

>>7042352
>can't into probability.
just google it. it's pretty simple

No, it's one hundred percent true. Try it out.

Get 23 people together, and it will almost always be someone's birthday, yet half the time, two of them will be having a birthday.

If you have trouble accepting the math behind this, you're in good company. Even Newton got it wrong on his first try, although Leibniz got it right immediately (admittedly, there has been a controversy that he might have already heard about it from a story about Newton getting it wrong, which one of his spies may have told him while bringing more notes on the calculus).

>>7042335
Why? Because your shitty intuition tells you so?

>>7042356
Lol, you're funny. Yep them french fries be legendary.

>>7042342
if you have an array of 10 spaces, then letting blocks fall randomly in any of them
most people would probably think you need to throw about 5 blocks to have a good chance to hit the same space twice...

would be cool to see the calculation to this example

>>7043201
The probability for two blocks of hitting different spaces is (9/10) because the second block has to hit an empty space. The probability for three blocks is (8/10)(9/10) since both the second and the third blocks have to hit empty spaces. When you get to fourth block you have (7/10)(8/10)(9/10)=50.4%.

Same story for birthdays.
(364/365)(363/365)(362/365)...(345/365)(344/365)(343/365) corresponds to the probability of 23 people's birthdays falling on different days and that's about 50%.

fuck

>i understand the math but there's no way this is possible
That's a weird sentence. I seldom come across people that deny the viability of combinatorics when dealing with a finite number of things.

Given that, in a group of 366 people, there is a 100% chance that two people share a birthday and the chance that at least three pairs of people share a birthday is >>95%.... it's not so far fetched that the chance is still at 50% once you go down to 23 people.

>>7042319
how is that a paradox
do you even science

Well of course its 50%, they either do or they done, that's two options so the probability is 1/2, or 50%.

>>7042319
the only thing wrong with this is that they call it a paradox.

its true, but thats besides the point considering it in no way fits the definition of a paradox.

>>7043513
i just did some calculations and this guy right here is legit

>>7043294
you forgot about leap years, dude.

>>7042335
If you think it must be wrong then you don't really understand the proof

>>7042319
The reason the probability is so high is because it doesn't say that if you gather 23 people then there's a 50% chance one of them will have YOUR birthday or two of them will share a particular day as a birthday. Instead you are looking at many pairs of people and so there are many possible pairs and thus the probability of one pair having the same birthday (which is an arbitrary day) is reasonably high. When considered this way I don't think the problem is particularly unintuitive.

>>7043517
The definition of a paradox is something that seems to be false but upon further inspection is actually true. Definition fits.

Just sat down and played some Sonic when it all became clear to me.

>>7042319
It is not a parodox.

a good survey was done at the FIFA world cup 2014 where the 32 squads of 23 people participated.

Turns out that 16 teams did have at least two players with the same birthday in them. Five teams had two pairs of players with the same birthday.

everyone post there birthday, they more it takes to get a duplicate the more suspicious we can be that some axioms may be wrong.

may 10

>>7043576
That's awesome

>>7043585
That's weird, I was born on May 10th.

>>7043585
May 10th here

amazing, it works!

>>7043585
May 10
Its 100% proven

>>7043585
may 10

>>7043585
I'm at a conference with about 50 people, and half the people here were born on May 10.

>>7042319
OP, your issue might be that you're thinking about it as the chance that any given person has the same birthday as someone else in the group. Think about it as the chance that any one of the twenty-three has the same as any one of the twenty-two others, and it should seem more reasonable.

>>7043585
may 10 here

>>7043588
>liking cuckball

>>7043585
5/10

>>7042356
Requesting this in caption style.
I'd do it myself, but my image editing skills are shit.

>>7043639

>>7042319
>i understand the math
no, you don't

>>7043795
kek

>>7043615
5th of October?
Crazy, that's my birthday!

>>7043795
Damn, David Gyasi was great in Interstellar.

>>7043795
Wow, Selma L. Jackson was great in 2001: A Space Odyssey.

>>7043542
According to wikipedia : "A paradox is a statement that apparently contradicts itself and yet might be true."

Here's a paradox :
This sentence is a lie.

I don't see how this probability is paradoxal.

Jan 7

Jan 8

>>7042319
People make up random stats all the time. It's more than likely that this "fact" was completely made up.

>>7043942
Strong bait.

>>7043576
NHL rosters have 22 or 23 people; from the first 10 teams I counted, 4 teams had players with same birthdays on their roster.

Lets find out. Birthday on 26 of June.

>>7043585
may 10

>>7042334
Both of those statements are false.
And so is this one: >>7042335