Identifiability problems in Hadwiger fertility graduation

Abstract

In a paper by Hoem & Berge some difficulties in Hadwiger and gamma fertility graduation were described. It is shown that some of these difficulties may be ascribed to the fact that both the gamma and the Hadwiger (or inverse Gaussian) distribution tend to the normal distribution when the coefficient of variation tends to zero. It is also shown how some of these problems may be avoided by a suitable reparametrization.