> We can ignore 100/400 year problem, for now, because our sample population (working age) were born before 2000. Actually, it's that they're born after 1900,

> We can ignore 100/400 year problem, for now, because our sample population (working age) were born before 2000. Actually, it's that they're born after 1900, because 2000 was a leap year, but you get the idea. > Wondering what you'd get from Bayesian. Maybe you wouldn't have to assume random distribution of birthdays? Like, maybe mothers really want to (or don't want to) have leap babies, so that slightly influences the likelihood of a Feb 29 birthday? Exactly - it's rather well-known that the distribution of birthdays isn't uniform (even for the other 365 days). It's only been ~10 minutes, so I'll wait a bit (in case any curious person wants to tackle this) before explaining some of the ways I was thinking that one could incorporate that information into the model .