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Hi,
Also, having a birthday in january sucks because I grew up getting birthday or Christmas presents, but not both.
My brother-in-law's birthday is the 27th of December. We make it a point to celebrate his birthday separately from Xmas ;)
Discuss.
Yessir. Done sir. :)
--Pete
How big was the aquarium in Noah's ark?
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03-26-2004, 11:50 PM
(This post was last modified: 03-26-2004, 11:51 PM by whyBish.)
Pete,Mar 27 2004, 09:35 AM Wrote:x
--Pete
Well, thats the stat for a given day, but how many times are you sampling?
The chance that there exists a day in the year where no lurker has a birthday
would be much higher.
--Edit Stop quoting whole posts :P
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Hi,
Yes, of course. The probability that someone has a birthday on any particular day is just 1 - (probability that no one has a birthday on that say). The probability that at least one person has a birthday on every day of the year is just that last number to the 365.25 power. So, the probability that there exists at least one day when no one has a birthday is just one minus this last number. Or, at least that's my zeroth order answer without much thought.
For the case of 500 people, the "answers" are
Probability of no birthday on a given day, P1 = (364.25/365.25)^500 = 0.2539
Probability of a birthday on a given day, P2 = 1 - P1 = 0.7461
Probability of a birthday on every day of the year, P3 = P2^365.25 = 3.455e-47
Probability of one or more days without a birthday, P4 = 1 - P3 = virtually 1
If we increase it to 2000 people, we get
P1 = 0.004156
P2 = 0.9958
P3 = 0.2185
P4 = 0.7815
(all calculations done on the Windoz calculator, no intermediate rounding, and answers *not* checked).
All such calculations can be fun. But they are nothing but counting problems. Sampling problems are much more interesting, IMO ;)
--Pete
How big was the aquarium in Noah's ark?
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Quote: We need to have a "Spend time with your SO day" on June 25.
SO?
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no terrible acronyms
Why can't we all just get along
--Pete
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Well, then. I guess I need to find a significant other to spend time with. A day after my Birth day. :)
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I'm bored, and have no SO, so I might as well list mine here.
23/m/Singapore(South East Asia)
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Let's see...
Too young for you/Can't think of witty quip to put here/My house, in front of my computer (like usual)
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Obi2Kenobi,Mar 30 2004, 12:00 AM Wrote:Let's see...
Too young for you/Can't think of witty quip to put here/My house, in front of my computer (like usual)
How do you know you're too young? I'm barely legal myself.
I'd be just fine with a straight answer, thankee much.
Where is your house, is what I'd like to know.
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Quote: How do you know you're too young? I'm barely legal myself.
Because I'm not even "legal." (14)
And my house is in Colorado (USA). :)
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Obi2Kenobi,Mar 30 2004, 11:16 PM Wrote:Because I'm not even "legal." (14)
And my house is in Colorado (USA). :)
Naga Trollops!
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Obi2Kenobi,Mar 30 2004, 11:16 PM Wrote:And my house is in Colorado (USA). :)
Colorado, huh? Too far away, all other things being equal (which they're not).
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