เปรียบเทียบวิธี

	Multiregional Migration Projection	Rogers-Castro Migration Schedule
สาขาวิชา	Migration Studies	Migration Studies
ตระกูล	Regression model	Regression model
ปีกำเนิด	1975	1981
ผู้ริเริ่ม	Andrei Rogers; Frans Willekens	Andrei Rogers & Luis J. Castro
ประเภท	Matrix cohort-component projection model for multiple interacting regions	Parametric curve-fitting model for age-specific migration rates
แหล่งต้นตำรับ	Rogers, A. (1975). Introduction to Multiregional Mathematical Demography. John Wiley & Sons, New York. ISBN: 9780471729945	Rogers, A., & Castro, L. J. (1981). Model Migration Schedules. IIASA Research Report RR-81-30.
ชื่อเรียกอื่น	Multiregional Cohort-Component Projection, Multistate Population Projection, Spatial Population Projection, Rogers Multiregional Projection	Model Migration Schedule, Rogers-Castro Curve, Multi-Exponential Migration Schedule, Age Profile of Migration
ที่เกี่ยวข้อง	3	3
สรุป	Multiregional migration projection extends the classic cohort-component method from a single closed population to a system of several regions that exchange migrants. Developed principally by Andrei Rogers in his 1975 Introduction to Multiregional Mathematical Demography, it replaces the ordinary Leslie matrix with a generalized growth matrix whose blocks carry not only survival and fertility within each region but also the age-specific probabilities of moving from every region to every other. Advancing a stacked population vector — population by age for each region — through repeated multiplication by this matrix projects all regions simultaneously and consistently, so that an out-migrant from one region becomes an in-migrant somewhere else and the system stays closed. The same matrix yields multistate life-table quantities such as expected lifetime spent in each region and the long-run stable spatial distribution of the population. Because the method demands smooth age-specific migration inputs, it is usually paired with Rogers-Castro model schedules, and the comparative findings of Rogers and Willekens's 1986 Migration and Settlement project established it as the standard apparatus of formal spatial demography.	The Rogers-Castro migration schedule is a parametric model that captures the remarkably regular way migration rates vary with age. Across countries and eras, the probability of moving is high in infancy, falls through childhood, surges to a sharp peak in the early adult labour-force years, and often shows a secondary bump around retirement. Andrei Rogers and Luis Castro, working at the International Institute for Applied Systems Analysis, formalized this regularity in their 1981 monograph as a sum of exponential and double-exponential curves whose parameters have direct demographic meaning. The simplest version uses seven parameters to describe the childhood decline and the labour-force peak; nine- and eleven-parameter extensions add retirement and post-retirement components. Fitting the schedule by nonlinear least squares smooths noisy age-specific rates, allows missing or sparse data to be filled in, and yields interpretable indices — the mean age of the labour-force peak, its sharpness, and the spacing between the childhood and labour curves. The result is a compact, comparable summary of an entire age profile of migration that feeds directly into multiregional projection and the analysis of migration selectivity.