The systematic component of variation in the distribution of open birth interval: an assessment.

In the present paper we have used a model of open birth interval OBI) to study the systematic component of variation in the length of open birth interval by taking a priori distribution of the risk of conception as the type III distribution. The approach is further extended to study the above component of variation in OBI regardless of parity and is illustrated a set of a priori values of the parameters involved in the model.(excerpt)