Systematic and chance components in fertility measurement.

Abstract A Monte Carlo simulation model of fertility is developed to incorporate a decline in fecundability with age of women as well as a variation between women, and a family planning strategy in which couples prefer certain sizes of families and seek to lengthen the last planned birth interval. In the simulation of family planning and non-family planning populations, segmental parity tables are computed. These are tables in which the numbers of women in the columns representing the completed family sizes are sub-divided by rows representing the sizes of the families for shorter durations of marriage. The couples' success in their plans, under various conditions, and the rapidity with which family sizes stabilize, are among the results obtained from the simulation. The application of the tables to the estimation of family size preferences from observed family size distributions is also discussed.