03-26-2004, 08:27 AM
It's actually pretty good odds. I'd say the chance that you WON'T see a birthday listed on the front page, for any given day of the year(barring Feb 29), is about 1 in 20. That is to say, about once every 20 days, you should see nobody's birthday listed. Based on my own casual observation.
Oh, and for the record, it's something like every 32 people=1 pair share their birthday. *looks it up in his Reader's Digest Strange Stories Amazing Facts 2 volume*
Page 194
Birthday Parties
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It is a fairly well-known fact that in any group of 23 people, there is at least a 50-50 chance that two of them share a birthday.
In a group of 5, the chance that two have the same birthday is just under 3 in 100; for 15 it climbs to just over 1 in 4; and for 23, it is nearly 1 in 2.
The reason lies in a quirk of statisticcs. As the size of a group increases, the number of possible pairs increases aas well - but at a faster rate. In a group of 5, there are 10 possible combinations of 2 people; in a group of 23, there are 253 possible pairs. *AKK's note. It(the number of possible pairings) increases exponentially as the total number of people increases geometrically*
In his book Lady Luck, the mathematician Warren Weaver relates how this curious fact came up in conversation during a dinner party for a number of army officers during World War II.
Most of Weaver's fellow guests thought it incredible that the figure was just 23; they were certain it would have to be in the hundreds. When someone pointed out that there were 22 people seated around the table, he put the theory to the test.
In turn, each of the guests revealed his birth date, but no two turned out to be the same. Then the waitress spoke up. "Excuse me," she said. "I am the 23rd person in the room, and my birthday is May 17, just like the general's over there."
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Why is the above significant? Well, if you consider the fact that we have 500(guesstimate) registered users who posted their DoB in their bios, the odds of any 2(beyond 100%), or 3, or even 6(probably low 10%s) of them sharing a birthday, would be pretty high. This reduces the potential number of "unique" birthdays.
Oh, and for the record, it's something like every 32 people=1 pair share their birthday. *looks it up in his Reader's Digest Strange Stories Amazing Facts 2 volume*
Page 194
Birthday Parties
--------------------
It is a fairly well-known fact that in any group of 23 people, there is at least a 50-50 chance that two of them share a birthday.
In a group of 5, the chance that two have the same birthday is just under 3 in 100; for 15 it climbs to just over 1 in 4; and for 23, it is nearly 1 in 2.
The reason lies in a quirk of statisticcs. As the size of a group increases, the number of possible pairs increases aas well - but at a faster rate. In a group of 5, there are 10 possible combinations of 2 people; in a group of 23, there are 253 possible pairs. *AKK's note. It(the number of possible pairings) increases exponentially as the total number of people increases geometrically*
In his book Lady Luck, the mathematician Warren Weaver relates how this curious fact came up in conversation during a dinner party for a number of army officers during World War II.
Most of Weaver's fellow guests thought it incredible that the figure was just 23; they were certain it would have to be in the hundreds. When someone pointed out that there were 22 people seated around the table, he put the theory to the test.
In turn, each of the guests revealed his birth date, but no two turned out to be the same. Then the waitress spoke up. "Excuse me," she said. "I am the 23rd person in the room, and my birthday is May 17, just like the general's over there."
=========================
Why is the above significant? Well, if you consider the fact that we have 500(guesstimate) registered users who posted their DoB in their bios, the odds of any 2(beyond 100%), or 3, or even 6(probably low 10%s) of them sharing a birthday, would be pretty high. This reduces the potential number of "unique" birthdays.