Mazur, Denis Peter2017-12-312017-12-311981Ruch Prawniczy, Ekonomiczny i Socjologiczny 43, 1981, z. 4, s. 173-1850035-9629http://hdl.handle.net/10593/21158A demographic model of fertility age curve is simulated to determine the effect of successive shitfs in women's aggregate age at birth. The age limits of women's reproductive span their age structure, and the annual number of livebirths are held constant in the first experiment" The second experiment involves an assessment of variation in women's reproductive-age span, Two experimental populations are distinguished: (1) the actual population by age, and (2) the life table type. The shape of age curve of fertility has a minimal affect on the cumulative rate for the life table age structure. When based on the actual population by single years of age, the cumulative rate of total fertility tends to fluctuate with changes in the peak age of women at childbearing. An increase in the average age of women at birth under the absolute constancy of parameter values usually augments the rate of total fertility. A slight decrease in completed fertility is observed for the life table type of age structure when the upper limit of women's reproductive span is advanced early. In the final simulation, when requirement of the constancy of parameter values is much relaxed the test corresponding to an intermediate value of the average age at childbearing generates the highest level of completed fertility. The author suggests that the most desirable approach seems to be a combination of analytic properties of the model with simulation.polinfo:eu-repo/semantics/openAccessArtykuł