To date, the concentration of fertility has been studied almost exclusively through the lens of indicators derived from the Lorenz curve of completed parity. Arguably, this situation has resulted from a misapplication of criteria from the study of income inequality, without fully considering the...

Conventional parametric count distributions, namely the Poisson and Negative-Binomial models, do not offer satisfactory descriptions of empirical distributions of completed cohort parity. One reason is that they cannot model variance-to-mean ratios below unity, that is, underdispersion, which is...