Sensitivity of model-based human mortality measures to exclusion of the Makeham or the frailty parameter

Adult human mortality is well captured by a gamma-Gompertz-Makeham model that accounts for the exponential increase in individual hazards, the existence of age-independent mortality component, and unobserved heterogeneity in the study population. The article studies the impact of neglecting statistically significant extrinsic mortality or frailty on human mortality measures: aggregate indicators like life expectancy, life disparity, entropy, and the Gini coefficient are little affected while the rates of individual and population aging, the modal age at death, and temporary life expectancy can be substantially distorted.