estimates a0 using the Andreev-Kingkade rule of thumb starting with IMR

Source: R/lt_rule.R

AKq02a0 Andreev Kingkade a0 method. This version has a 3-part segmented linear model, based on cut points in q0. Code ported from HMDLifeTables.

lt_rule_ak_q0_a0(q0, Sex)

Arguments

q0

a value or vector of values of q0, the death probability in the first year of life.
Sex

either "m" or "f"

Value

a0, the estimated average age at death of those dying in the first year of life, either a single value or a vector of a_0 values.