Analysing open birth interval distributions.

Summary This paper began with the recognition that open birth interval distributions are analogous to age distributions. It then became clear that closed birth interval distributions are, somewhat more loosely, analogous to mortality schedules, and that the relationship between open and closed birth interval distributions could be explored by imitating the formal demography of mortality and age distribution. Pursuing this programme, we develop the formal demography of open and closed birth interval distributions and show that under certain assumptions open interval distributions may be used to estimate closed interval distributions, just as age distributions may be used to estimate mortality. An illustrative application to Indonesian data is given.