An Empirical Analysis of a Disequilibrium Model of Fertility Behavior and the Threshold Hypothesis : 1973 Philippines

This paper examines a model of fertility behavior in which some women have excess capacity to bear children, while others have excess demand. This idea, which has not received adequate attention in econometric analyses of fertility behavior with the exception of Encarnacion's studies, underlies current explanation of certain demographic phenomena including the persistence of high birth rates in LDCs that have achieved low mortality rates. In this study, the implications of the model regarding the fertility effect of life expectancy are examined and tested. In conformity with the model's prediction, life expectancy appears to have an insignificant effect on the fertility of wives with educational attainment below elemantary grade and family income below P2,500 in 1973. Among higher income and more educated women, however, the effect of life expectancy at birth is significantly negative and the estimated elasticities appear to be in the order of - .72 and -1.15. The model was also tested by examining age at marriage. The hypothesis is that individuals marry later the larger the expected excess capacity to bear children to minimize unwanted births. If the model under consideration is correct, the conjectures, which are confirmed by the empirical results, are: (1) education above elementary should have a significantly positively influence on the age at marriage inasmuch as excess capacity is expected to be larger the more educated the women is; (2) below elementary grade, however, it should have no effect since women in this situation are expected to have excess demand for births.