Census-based measures of fertility, mortality, and migration Hist 5011

Fertility: Yasuba 1962 Measure ratio of women aged to children aged 0-4 for each state (or county) Correlate with characteristics of state (e.g. land availability, sex ratio, ethnicity)

Fertility: Coale and Zelnik 1963 Begin with single-year age distribution Adjust for mortality Adjust for census underenumeration Yield: number of births in each year, back to 1800 Suggested very early fertility decline

Limitations No information on marital fertility No age-specific rates (cannot look at stopping vs. spacing) Cannot study differentials between population subgroups (e.g. different occupations)

Microdata allows own-child fertility analysis Retherford and Cho, 1978 Calculate mean number of children of each age living with mothers of each age Adjust mean upwards to reflect mortality of children, underenumeration, and children residing without mothers Yields estimates of age-specific marital fertility

Simple own-child approach Even if we can make rough estimates of adjustments for whole populations, we cannot do so for population subgroups Therefore, adjustments make no sense when studying fertility differentials Simple own-child approach uses no adjustments: just measure mean children under 5 with mothers of each age.

Children ever born Limitation: we don’t know when they were born Best for study of completed fertility Can calculate cohort parity distributions for older women Allows cohort-parity analysis (David and Sanderson 1987)

Mortality: Two-Census methods Get two adjacent censuses Adjust population counts at each age for immigration, emigration, and changes in net underenumeration Subtract to estimate number of deaths Divide by midpoint of population to estimate age-specific death rates Rough estimates only, since effects of adjustments are large

Mortality: Children-ever-born and children surviving Calculate percent of children born surviving by age of mother Standardize or focus on a particular age group Can be used to study differentials With fancier techniques, can be used to estimate age-specific death rates for young people (Preston and Haines 1991)

Migration: Net migration estimates from aggregate data Eldridge and Thomas 1960 Similar to two-census mortality estimation Get age distributions by state Adjust for mortality and differential underenumeration The remaining difference between time periods is net migration Result: slow upward trend in migration since 19 th century

Migration: Using birthplace information Calculate percent of native-born persons residing out of their state of birth Works especially well for lifetime migration (Kelly Hall and Ruggles forthcoming)

Migration: Record linkage Thernstrom 1963 and many others Ferrie 2004 New 1880 linkage project

Migration: Using children present Can be tricky Easiest measure, if you have enough cases: just look at persons who have children of a particular age Large potential for selection bias

Migration: residence 5 years ago Good since 1940 U.S., 1960s or 1970s in other countries Focus on recent migration Allows many methods