Dating someone with the same birthday
But P(same day) should be roughly independent of whether you were born in the same year.
So it will be $\approx$ P(Same year) $\times$ P(Same day).
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Visit Stack Exchange Cross Validated is a question and answer site for people interested in statistics, machine learning, data analysis, data mining, and data visualization. Sign up to join this community I share the same birthdate as my boyfriend, same date but also same year, our births are seperated by merely 5 hours or so.
From experience I'd guess around 20% or so, no way to seriously calculate that, but no matter what it exactly is, just want to be clear having a special weird connection means nothing (though it is fun).
Then, something the other didn't take into account, looking at birth rates per month we get a nice overview (it's caused by things like people being off thus having a lot of free time on hand 9 months before the months in question), next dividing that percentage by the number of days in that month.
You can see how it isn’t quite as easy as just x/365!My point was that the chances are tiny if you consider the probabilities of being in a relationship ( being successful at it for X amount of time).I find the amount of factors to take into account quite vast (up to a point, gender and age, availability, probabilities of separation in our region, etc.) Is it even possible to calculate the probabilities on something like this? For any one relationship, the odds of sharing the same month and day are approximately 1 in 365 (not exactly because of leap year and because births are not exactly evenly spaced within a year.A consequence of this is that the pool of people you know from the exact same ages is by guesstimation a factor of 5 bigger than the expected value, if $age If it's an event specified before the fact, you can simply break it down: The chance that your boyfriend was born the same year as you is actually very high (especially given many situations tend to bring people of very similar age together); it's a very difficult probability to calculate, though, without data.
If you had that probability, P(Same day and same year) = P(Same year) $\times$ P(Same day|same year).
It’s like if I had a 1/10 chance of winning the lottery and I meet another person who also has a 1/10 chance of winning the lottery, then combined we have a 2/10 chance of winning the lottery.