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what does this mean, s1

lololollllllllllll.pngwhat on earth does sigma "n-1" mean? i worked out the std dev, and was close to the correct value (26.84)... what does the n-1 mean? anything significant? thanks :smile:
Reply 1
Avatar for JackB784
JackB784
7
Did you divide by n-1 then square root?
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davros
16
Original post by Mr Tall
lololollllllllllll.pngwhat on earth does sigma "n-1" mean? i worked out the std dev, and was close to the correct value (26.84)... what does the n-1 mean? anything significant? thanks :smile:


There are 2 versions of the variance formula - one involving n and the other involving n-1. Make sure you're using the correct one!
Reply 3
Avatar for Mr Tall
Mr Tall
OP
9
Original post by JackB784
Did you divide by n-1 then square root?

why do i do n-1?
Reply 4
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JackB784
7
Original post by Mr Tall
why do i do n-1?


I think if it's a sample you do n-1

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