Difference between revisions of "Talk:2046: Trum-"

Explain xkcd: It's 'cause you're dumb.
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(More Math)
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This is not that weird.  If names were random then it would be a 1 in 26^4 = 456976 chance of a particular president matching another for the first 4, but this is a "Birthday Problem" with 44 presidents, so the probability of any two presidents sharing the first 4 characters is 456976!/(456976^44 (456976 - 44)!), which wolfram alpha is giving me a clearly incorrect answer of 0.99793...  but anyway, the point is the number won't be that low... where did I go wrong anyone?
 
This is not that weird.  If names were random then it would be a 1 in 26^4 = 456976 chance of a particular president matching another for the first 4, but this is a "Birthday Problem" with 44 presidents, so the probability of any two presidents sharing the first 4 characters is 456976!/(456976^44 (456976 - 44)!), which wolfram alpha is giving me a clearly incorrect answer of 0.99793...  but anyway, the point is the number won't be that low... where did I go wrong anyone?
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Apparently an approximation to the correct probability would be to do 44^2/(2 x 26^4) which would give about 0.2% chance of this happening.  So fairly weird, but as the comic suggests, many things about this presidency are weirder than 0.2%.

Revision as of 15:53, 14 September 2018


This is not that weird. If names were random then it would be a 1 in 26^4 = 456976 chance of a particular president matching another for the first 4, but this is a "Birthday Problem" with 44 presidents, so the probability of any two presidents sharing the first 4 characters is 456976!/(456976^44 (456976 - 44)!), which wolfram alpha is giving me a clearly incorrect answer of 0.99793... but anyway, the point is the number won't be that low... where did I go wrong anyone?

Apparently an approximation to the correct probability would be to do 44^2/(2 x 26^4) which would give about 0.2% chance of this happening. So fairly weird, but as the comic suggests, many things about this presidency are weirder than 0.2%.