Thursday, September 4, 2008

Excel STDEV Formula

They never have enough fun finding ways to frustrate us. Something so simple as a basic standard deviation. And they can't even get that right.

All I did was create a column of numbers from 1 to 40. The standard deviation of the first N natural numbers is known to be rt( (N^2 -1)/12) - which is 11.543396 - I manually did a laborious sum of xi minux xmean and computed the stdev this way in Excel and got this. And, I used the Excel built in - which gives 11.69045194.

What the hell!!

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