Birthday Stats

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Mushroom
Deinonychus

Joined: 24 Mar 2007
Gender: Male
Posts: 396

30 Mar 2007, 3:36 am

Wow, two other people here share my birthday, September 22nd... but I was born on 1992.

lau
Veteran
Veteran

Joined: 17 Jun 2006
Age: 76
Gender: Male
Posts: 9,798
Location: Somerset UK

30 Mar 2007, 9:36 am

Interesting one, that. I had to do a bit of research, to confirm things, but it's probably not surprising that someone has "noticed" that they are the third person with the same birthday.

The mis-named "Birthday Paradox" (because it's not a paradox at all) is that given 23 people, the probability that at least two have the same birthday is greater than 50%. (Or, stated the way it's easier to calculate, the probability that all 23 have different birthday is less than 50%).

What I had to dig a bit to find was the three person case. For that, the figure is 88 people.

This thread has only got 30-odd bithdays in it, so it's not in the slightest surprising that there's a pair. (For 29 people, the odds are 2 to 1 against them all have different birthdays, for 42 people, 10 to 1 against)

Anyway, the triple coincidence isn't much of a surprise. Although there aren't enough entries here to make it better than 50% probable, on the face of it, imagine how many more people have glanced at the thread (1077 views), at in particular looked at page one, where that magic early pair of birthdays matches has been shown since near the beginning. Naturally, Mushroom, whether you looked at the thread intending to add your birthday to the list, or not, when you saw that there were already two with your birthday, how could you resist!

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"Striking up conversations with strangers is an autistic person's version of extreme sports." Kamran Nazeer

Star
Deinonychus

Joined: 8 Mar 2007
Age: 63
Gender: Female
Posts: 337
Location: Amsterdam, Netherlands

30 Mar 2007, 5:23 pm

Thursday, December 7, 1961 at 10:48am, on 37.58 North by 23.46 East

Sun and Moon in Sagittarious, Ascedant in Aquarious

Star

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Autism is a reality that seems to the neurotypicals like a bad dream, while it is their reality that is the true nightmare...

BigT
Velociraptor

Joined: 22 Mar 2007
Gender: Male
Posts: 443
Location: Basingstoke, England

04 Apr 2007, 11:15 am

September 23rd, 1990.
Right inbetween Libra and Virgo (I am more like a Virgo)

sinsboldly
Veteran
Veteran

Joined: 21 Nov 2006
Gender: Female
Posts: 13,488
Location: Bandon-by-the-Sea, Oregon

14 Apr 2007, 10:02 am

November 20

Sun in Scopio
Moon in Aries
Ascendent in Virgo
Mercury in Sag
Venus in Scorpio
Mars in Capricorn
Pluto in Leo

Sobriety Date: 9/11 (no, not THAT year!)

Merle