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RE: What's the probability that 3 out of 23 people will share the same birthday?
January 24, 2022 at 8:02 am
(January 24, 2022 at 4:26 am)Abaddon_ire Wrote: (January 24, 2022 at 2:06 am)FlatAssembler Wrote: So, where do you think the error lies? https://flatassembler.github.io/birthday_paradox.aec
The error is that you do not understand any of it.
Is that clear enough?
Why do you think that I do not understand any of it? It's written in a programming language I made, so I understand precisely what each directive means. And it's an algorithm I made up, so I understand it as well.
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RE: What's the probability that 3 out of 23 people will share the same birthday?
January 24, 2022 at 10:59 am
(January 24, 2022 at 2:06 am)FlatAssembler Wrote: (January 22, 2022 at 7:02 am)BrianSoddingBoru4 Wrote: Your programme is flawed. If I enter '100' in the collisions field, the probability computes at 0%. This means that in a group of 23 people, there is no chance that they all share the same birthday. While such a coincidence is statistically unlikely, the probability is non-zero.
Boru So, where do you think the error lies? https://flatassembler.github.io/birthday_paradox.aec
Fairly sure it’s a programmer error.
Boru
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RE: What's the probability that 3 out of 23 people will share the same birthday?
January 24, 2022 at 11:01 am
(This post was last modified: January 24, 2022 at 11:05 am by GrandizerII.)
Wild guess. Probably to do with some limitation related to number of decimal places?
If the answer just keeps approaching 0 as you increase the input number, then inevitably you're going to get 0 as the answer with a very large input number like 100 because it can't handle too many decimal places.
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RE: What's the probability that 3 out of 23 people will share the same birthday?
January 24, 2022 at 9:18 pm
(This post was last modified: January 24, 2022 at 9:18 pm by brewer.)
(January 24, 2022 at 11:01 am)GrandizerII Wrote: Wild guess. Probably to do with some limitation related to number of decimal places?
If the answer just keeps approaching 0 as you increase the input number, then inevitably you're going to get 0 as the answer with a very large input number like 100 because it can't handle too many decimal places.
Please tell me that handling too many decimals is a euphemism. 
Being told you're delusional does not necessarily mean you're mental.
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RE: What's the probability that 3 out of 23 people will share the same birthday?
February 13, 2022 at 11:07 am
@ polymath257 Perhaps you know the answer to this question?
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RE: What's the probability that 3 out of 23 people will share the same birthday?
February 14, 2022 at 4:55 am
Personally, I blame hippies.
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RE: What's the probability that 3 out of 23 people will share the same birthday?
February 14, 2022 at 8:32 am
(February 13, 2022 at 11:07 am)FlatAssembler Wrote: @polymath257 Perhaps you know the answer to this question?
If there is not an analytic solution, then, there's an approximation, and certainly, a simulation.
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RE: What's the probability that 3 out of 23 people will share the same birthday?
February 14, 2022 at 12:36 pm
(This post was last modified: February 14, 2022 at 12:37 pm by onlinebiker.)
The odds get way better in queue at the DMV...
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RE: What's the probability that 3 out of 23 people will share the same birthday?
February 16, 2022 at 12:15 am
(This post was last modified: February 16, 2022 at 12:17 am by Paleophyte.)
(January 21, 2022 at 2:06 am)FlatAssembler Wrote: The probability that 2 out of 23 people will share the same birthday is slightly higher than 50%, and that is the famous Birthday Paradox. However, what is the probability that 3 out of 23 people will? I have, like I have written in this article about something distantly related to that, estimated numerically using Monte Carlo method that it is around 1.26%, and that the probability that 4 out of 23 people will share the same birthday is around 0.018%. However, I am interested whether there is a general formula for that.
As OLB alludes to above, there is insufficient information to answer this question. Nowhere does it say that these people are randomly selected. If you're in a neonatal unit then the odds that 3 of the 23 infants don't share a birthday are vanishingly small. Conversely, if you've carefully selected for two of each zodiac sign then you're nearly* guaranteed not to have more than two birthdays on any given day with low odds of even that.
For extra credit: You and 49 friends live in one of each of the 50 capitols of the states of the USA. Your birthdays are distributed randomly and you all visit the birthday boy(s) and/or girls(s) in their hometown on their birthday. What is the total minimum probabilistic travel distance for all of your friends in a year? Kindly do not ignore leap years, the curvature of the Earth, or that suspicious burning odour coming from your processor as you attempt to simulate this.
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