Can anybody help me with this: Suppose you have a small set of values data:=[0.0630, 0.1050, 0.1560] and you're wondering what's the standard deviation of data with the "old" stats package you'll get with(stats): describe[standarddeviation](data) 0.03802630668 with the new Statistics package (which is supposed to replace stats) you'll get with(Statistics): StandardDeviation(data) 0.04657252409 The stats package will assume (unless told otherwise) that it must compute the standard deviation of a population, while the Statistics package will assume that it must compute the standard deviation based on a sample.