Undergrad Does Using 365.25 Instead of 365 Affect the Birthday Problem Calculation?

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Using "365.25" instead of "365" in the birthday problem calculation yields minimal differences in results, with probabilities varying slightly. The discussion highlights the importance of considering leap day rules and the empirical probability of birthdays, which may not be uniform throughout the year. A model that is suitable for undergraduates while converging to empirical probabilities is sought. Contributors are encouraged to share their insights, and there is a request for permission to cite usernames in the final text. Overall, the conversation emphasizes the need for accuracy and clarity in mathematical modeling for educational purposes.
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Has anyone seen this alternative?
Has any solver replaced "365" by "365.25" in the standard approach? I'm editing a book, and don't want unpleasant surprises when it appears. Please include URRL's and ancillary information. Finally let me apologize to site coordinators if this is off the reservation. Thanks!
 
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You could take the standard approach and extend the period to 400 years to cover all possible leap day rules.
 
Ben2 said:
Summary:: Has anyone seen this alternative?

Has any solver replaced "365" by "365.25" in the standard approach? I'm editing a book, and don't want unpleasant surprises when it appears. Please include URRL's and ancillary information. Finally let me apologize to site coordinators if this is off the reservation. Thanks!
It doesn't make a lot of difference, for the obvious reason.
 
I was unaware of other leap day rules as posted by fresh_42, but may reference that in the book. On PeroK's comment, using 365 and 366 give answers differing by .001 to 4 d.p.'s; but 365.25 gives me a smaller probability.
The question is, Which model is simultaneously suitable for an undergrad readership and converges (Law of Large Numbers) to the empirical probability?
Thanks for all comments and references provided.
 
Ben2 said:
The question is, Which model is simultaneously suitable for an undergrad readership and converges (Law of Large Numbers) to the empirical probability?
Thanks for all comments and references provided.
The empirical probability would take account of the non-uniform pattern in births throughout the year.
 
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Ben2 said:
I was unaware of other leap day rules as posted by fresh_42
An interesting consequence of which is that the 13th of the month falls on a Friday a little more often than 1/7.
 
Thanks for all comments to this point. Since I've been trained to cite contributors at every opportunity, please
indicate if you do not want your site username used in the final text. Otherwise only my publishers or this site's gatekeepers will prevent appropriate recognition of your assistance.
 

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