Going toward to our 1.0 release, I'd like to create consistency across our weighted statistics. Conceptually, theses weights represent frequency counts, i.e., multiplicities of input values.
So far, our documentation does not state any restrictions on these weights but some runtime operations require integer data (I), while others allow arbitrary floating point data as indicated below: * moment * cov * aggregate * table * median (I) * quantile (I) * interQuartileMean (I) This can lead to unexpected errors as shown by recent issues such as SYSTEMML-1265. Looking back to R and its packages like Hmisc or reldist, it turns out that they all allow arbitrary weights. So, relaxing any restrictions of integer weights seems like the right choice. As this changes the external behavior - albeit in a generalizing manner - we should make this change now. If you have any concerns, let me know. Regards, Matthias