Definition of a Population

Population Parameters

Assumptions (all individuals average, identical), age class zero

Horizontal versus vertical life tables (cohorts, segments)

Actuaries: average number of deaths at every age in population

(frequency distribution of age at death)

Age-specific death rates, q(x) = force of mortality

Survivorship, l(x), fraction surviving to age x

(probability that a newborn will survive to age x

Three types of survivorship curves (Types I, II, and III)

Age-specific fecundity, m(x)

alpha = age of first reproduction, omega = age of last reproduction

Realized fecundity at age x, l(x) times m(x) = l(x)m(x)

Net reproductive rate, R(0), replacement rate of population

Expectation of further life at age x, E(x)

Reproductive value at age x, v(x)

Residual reproductive value at age x, v*(x)

Generation Time, T

Stable age distribution

Type III survivorship. Heavy juvenile mortality

Type III survivorship. Heavy juvenile mortality

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