手法を比較

	Brass P/F Ratio Method	Brass Growth Balance Method
分野	人口学	人口学
系統	Process / pipeline	Process / pipeline
提唱年	1964	1975
提唱者	William Brass	William Brass
種類	Indirect fertility estimation adjusting period rates using reported parities	Death distribution method for estimating the completeness of death registration
原典	Brass, W. (1975). Methods for Estimating Fertility and Mortality from Limited and Defective Data. Carolina Population Center, University of North Carolina at Chapel Hill.	Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell. ISBN: 9781557864512
別名	P/F Ratio Method, Brass P/F Ratio Technique, Parity/Fertility Ratio Method	Brass growth balance equation, GBM, Death registration completeness estimation, Brass Büyüme Dengesi Yöntemi
関連	4	4
概要	The Brass P/F ratio method is the foundational technique of indirect fertility estimation, designed to correct fertility levels in populations whose vital registration is incomplete but where a census or survey reports both recent births and lifetime children ever born. It compares F — the period fertility a synthetic cohort would have accumulated by each age — with P, the average parity (children ever born) actually reported by women of that age. The ratio of the two diagnoses and corrects errors in the reported level of current fertility, yielding an adjusted total fertility rate from data too defective for direct calculation.	The Brass growth balance method estimates how complete a country's death registration is when vital statistics are incomplete but a census age distribution exists. Developed by William Brass in 1975, it rests on a simple demographic accounting identity applied above every age: in a stable population the rate at which people enter an open-ended age group must equal the population growth rate plus the rate at which they leave it by dying. Plotting the entry rate against the observed death rate above each age yields a straight line whose slope reveals the fraction of deaths actually registered.