As you may have guessed, this is a compilation, or a list if you're that kind of person, of people's birthdays. Give me your birthday and you shall be added to my list.
There's 74 users (including me, my birthday is 6/30/93) and there are two pairs of shared birthdays. According to Soccerdude's claim, we should have between 0 or 3 pairs at this point.
Soccerdude2's claim is, in theory, correct if we were to assume that each of the 365 days in a year (February 29 not included) had an equal number of birthdays of the people in this world. Other than that, it has nothing to do with statistics. It is a matter of probability.
The fact remains that your % chance of someone sharing a birthday with someone else in the room, assuming it is truly random, is 23/365, which is 6.3%.
No. I'm not sure how you came up with this, but this is not true.
To determine the probability in which no one in a room of 23 shares a birthday, let us consider each person separately and in order. Allow Person 1 to have any birthday (365/365). Now the probability for Person 2 to not share a birthday with Person 1 is (364/365). Similarly, the probability for Person 3 to not share a birthday with the former two is (363/365). Continue on and you get to Person 23 with 343/365. If we were to multiply this out, we would receive the probability in which no one shares a birthday, which equates to roughly 49.3%. Subtract from 1 (1 - .493), and we have 50.7%, the probability in which two or more people share a birthday in a room of 23 people.
If we were to multiply this out, we would receive the probability in which no one shares a birthday, which equates to roughly 49.3%. Subtract from 1 (1 - .493), and we have 50.7%, the probability in which two or more people share a birthday in a room of 23 people.
Followed you up to here, and now I have absolutely no clue where you get 49.3%. 343/365 = .94 approximately, which means there's a 94% chance of not sharing a birthday, OR, conversely, a 6% chance of sharing...which is what I said earlier.
So yeah. Please elaborate on how you got 49.3% and 50.7%.
Followed you up to here, and now I have absolutely no clue where you get 49.3%. 343/365 = .94 approximately, which means there's a 94% chance of not sharing a birthday, OR, conversely, a 6% chance of sharing...which is what I said earlier.
Sorry, I wasn't too clear. What I meant by "multiply this out" was this:
Basically Kasic like rayoflight3 said you take the chance of someone not sharing a birthday with someone else (364/365) and then someone else not sharing a birthday with both of them (363/365) and so on (362/365)(361/365)(360/365)(359/365)...(343/365) and multiply them together to get the total chance of 23 people not sharing a birthday (49.3%). Subtract that from one and you get the opposite, the chance that someone shares a birthday with someone else in that room of 23 (50.7%).
The key is thinking of any person out of the 23 sharing a birthday with any other person out of the 23.
Here's an updated list doing what I should have done long ago, removing the innactive/banned. If you have been removed and would like that to change then just say so.
I shall not add you then, I'm fairly confident about other people being above the limit but I've not come in enough contact with you and you seem far too protective of your age so I shall not add.
