I posted a question earlier but failed miserably in trying to explain what I am looking for (thanks to those who tried to help me anyway). Will try again, starting with a clean sheet.
Standard deviations are sensitive to scale. Since I am trying to perform a statistical test where the best result is predicted by the lowest standard deviation amongst different data sets, is there a way to "normalize" it for scale, or use a different standard-deviation-type test altogether?
Unfortunately dividing the resulting standard deviation by the mean in my case does not work, as the mean is almost always close to zero.