Spotting patterns in birthdays

[andrewducker]

from

The basic one of "When it's cold outside people stay in and have sex" is fairly obvious.

But laying things out like this, you can see the faint horizontal line that shows that nobody wants to give birth on the 13th.

And that medical staff _really_ don't want to work at Christmas. Or Independence Day.

Comments

[momentsmusicaux]

Might the big white column in November be Thanksgiving? (I don't actually know when that is, just guessing.)

[adrian_turtle]

you can see the faint horizontal line that shows that nobody wants to give birth on the 13th.

That also includes reporting errors. A friend of mine was born around 1am on the 13th of the month, more than 40 years ago. Her birth was officially recorded as being on the 12th of the month. The person at the hospital who certified such things presumably wanted her to have an auspicious start, and her parents were kind of distracted at the time. (Her own child actually was born on the 12th of the month. A different month, obviously.)

[pseudomonas]

For February babies, there seems to be a desire to have them on Valentine's Day.

[sinpar]

Fascinating stuff.

[cangetmad.livejournal.com]

Depressingly high evidence of elective Caesarians - look at Valentine's Day as well as the holiday periods.

[rhythmaning.livejournal.com]

I think I'd have expected a peak in the spring, too - after all those summer romances.

[bookzombie.livejournal.com]

I'm kinda surprised there isn't a bigger peak in November - 9 months after Valentines (I'm almost certainly a Valentines baby!)

[simont]

It's a shame the data only gives rank and not absolute frequency figures. I was hoping to use it to work out the real answer to how many people you need in a room before there's a better than 1/2 chance of a shared birthday.

(The usual answer of 23 assumes all possible birthdays are equiprobable. If I remember rightly, any divergence from that will reduce the figure even further.)

[ipslore.livejournal.com]

Also, the week-long block of Thanksgivings.

[aiela.livejournal.com]

I am going to show this to my coworkers - we have a long standing thing about how we never have any employees with November birthdays (we do birthday celebrations) and this shows why - November birthdays are far less common.

[widgetfox.livejournal.com]

I continue to be enchanted that Prince Charles was born nine months after Valentine's Day.

[davidcook.livejournal.com]

I'd love to see an Australian / Southern hemisphere version of this - our winter doesn't align with the Christmas/NY holiday period, would be interesting to see where the peaks are.

[barondave.livejournal.com]

The data was births from 1973-1999 so I'm technically not on it. Still, my birthday (4/13) is on one of the lighter days. My mother claims I was "nine months to the day" after their marriage, and they had a summer ceremony.

[akicif.livejournal.com]

Neat! It'd be nice to have day of the week info too, though.

[camies.livejournal.com]

I was born in mid-November so would appear to be a Valentine's baby - but was born a month prematurely so was conceived in March. Premature birth runs at 8 to 12 percent in the 'developed' world - enough to skew the figures I would think.

[pr1ss.livejournal.com]

You may also be able to find statistics for day of the week, or time of day. Late afternoon on Fridays, and just before shift changes tend to influence the surgical delivery rate. Doctors even admit to this. They say that they don't want to leave someone they have been attending, for their colleagues on the next shift to have to deal with.