Math Is Fun Forum

waynesmithie

Guest

variance and standard deviation

what is the difference between variance and standard deviation, other than that the standard deviation squared is the variance? both measure the spread of data, don't they?

also, why is the stand deviation of 1,2,3,4,5 sqrt(3)? how does this tell me about the spread of data?

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: variance and standard deviation

Hi waynesmithie;

All your questions are answered here.

http://www.mathsisfun.com/standard-deviation.html

Please cover the page above and then you will have a better understanding.

Another reason the sd is preferred over the variance is that the sd is in the same units as the data.

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