Hi, I see that org.apache.commons.math3.stat.descriptive.DescriptiveStatistics uses the singleton update formulas (from Pebay) for calculating (un-normalized) moments up to the 4th moment. Is there some reason that org.apache.commons.math3.stat.descriptive.SummaryStatistics excludes both third and fourth central moments?
Is it just a matter of computational efficiency, ie. DescriptiveStatistics calculates moments only when the getter is invoked (and all orders need not be calculated at once) while the "storeless" SummaryStatistics would need to calculate all 4 orders at every call to update()? Or is there some other blocker? Thanx, Mike Brzustowicz
