Re: pooled standard deviation

["Andreas J. Guelzow" <aguelzow pyrshep ca>]

On Tue, 2012-01-31 at 20:45 +0100, Frederic Parrenin wrote:
> Dear Gnumericers, (or dear Andreas ;-) )
>
> Is there a function to compute the pooled standard deviation of a serie?

If you have the raw population data for 2 series with the same mean,
then the pooled (population) standard deviation is just the population
standard deviation of the combined series.

More likely you have two sample series with slightly distinct sample
means. We do not have a specific function for this. You may want to use
(STDEV(series1)*COUNT(series1)+STDEV(series2)*COUNT(series2))/COUNT(series1,series2)

Andreas