R rbcc Junior Member Joined Nov 18, 2009 Messages 126 Feb 6, 2011 #1 Hi, I have a quick question, is this a formula for variance? \(\displaystyle \Sigma \ X^2\) \(\displaystyle -\) \(\displaystyle \frac{(\Sigma \ {X)}^2}{N}}\) Thank you!

Hi, I have a quick question, is this a formula for variance? \(\displaystyle \Sigma \ X^2\) \(\displaystyle -\) \(\displaystyle \frac{(\Sigma \ {X)}^2}{N}}\) Thank you!

tkhunny Moderator Staff member Joined Apr 12, 2005 Messages 9,790 Feb 6, 2011 #2 ...Only if you divide by N.