Equation 3 · Part 5 · How Demography, Migration, and Urban Futures Actually Work
=
=
What this part means
The expressions on both sides represent the same quantity under the stated assumptions.
Its job in the formula
The equals sign connects the complete expression on the left with the complete expression on the right. Both sides must have compatible units.
Full expression→=→Article meaning
The passage around this formula
The UN Population Division builds its projections using the cohort-component method : rather than extrapolating total population, it starts from the population by single year of age and sex in a base year, and ages every cohort forward one year at a time by applying age-specific and sex-specific survival probabilities (mortality), age-specific fertility rates applied to women of reproductive age (which generates the next year’s births), and net international migration assumptions applied by age [ 1 ] . Formally, for an age group a in year t : . where is the population in age group a at time t , is the survival rate applied to that cohort, and is net…
Learn the underlying idea
An equals sign says that the expression on its left and the expression on its right have the same value under the stated definitions and assumptions.
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Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.