The distribution by age of the frequency of first marriage in a female cohort

The schedule recording first marriage frequencies has been shown to take the same basic form in different populations, with differences only in the origin, area, and horizontal scale. It is shown here that a representative schedule is very closely approximated by a simple closed form frequency function, which is the limiting distribution of the convolution of an infinite number of exponentially distributed components. The schedule is approximated equally well by the convolution of a normal distribution (of age of entry into a marriageable state) and as few as three exponentially distributed delays. The latter convolution provides a plausible model of nuptiality, a model that receives surprising empirical support.