เปรียบเทียบวิธี

	Parity Progression Ratio	Net Reproduction Rate
สาขาวิชา	ประชากรศาสตร์	ประชากรศาสตร์
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	1953	2001
ผู้ริเริ่ม	Louis Henry (formalized in modern demography)	Richard Böckh and Robert Kuczynski (formalized in Preston, Heuveline & Guillot)
ประเภท	Order-specific fertility measure built from a sequence of conditional progression probabilities	Period measure of generational replacement combining fertility and mortality
แหล่งต้นตำรับ	Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell. ISBN: 9781557864512	Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell. ISBN: 9781557864512
ชื่อเรียกอื่น	PPR, Birth progression ratio, Parity progression probability, Doğum Sırası İlerleme Oranı	NRR, Net reproduction ratio, Net reproductive rate, Net Üreme Hızı
ที่เกี่ยวข้อง	4	4
สรุป	A parity progression ratio is the conditional probability that a woman who has already had a given number of children goes on to have one more. By converting a static parity distribution into a sequence of birth-by-birth transition probabilities, the method reveals where childbearing stops within a cohort and lets demographers rebuild completed fertility from the bottom up. It is the natural fertility analogue of a survival or life-table transition, treating each additional birth as a further step a woman may or may not take.	The net reproduction rate (NRR) is the demographic measure of generational replacement: the average number of daughters a woman would bear who survive to the age their mother was when she bore them, given the period's age-specific fertility rates and female mortality. By combining fertility with survival, the NRR answers the fundamental question of whether a population is replacing itself — an NRR of one means each generation of women exactly reproduces the next, below one signals long-run decline, and above one signals growth.