Comments on the application of variance analysis to the X-ray diffraction of polymers

The variance parameters K, L and M are given respectively by p 〈t⁻¹〉, p²g′(0) and −½p³g′′(0), where g(t) is the column-length distribution function and p is the `true' particle size. The exponential expression V(t) = p³exp(−β|t|) implies that L = K², M = K³, and cannot be correct in general. Its application in particular cases could be verified empirically by a study of the variance–range curve.