Volume 49 - Article 38 | Pages 1063–1086  

Dynamics of the coefficient of variation of the age at death distribution

By Jacob Martin, Jose Manuel Aburto, Iñaki Permanyer

Abstract

Background: Indicators of lifespan inequality, such as the life table entropy or variance of age at death, provide a measure of inequality in the timing of death. A range of indicators of relative and absolute inequality exist, and their evolution over time and sensitivity to changes in age-specific mortality have been studied. However, the coefficient of variation, a relative indicator defined as the standard deviation divided by the mean of the age at death distribution, has yet to be studied, and the existence and form of the threshold age has not been determined.

Results: As with other lifespan inequality indicators, changes in the coefficient of variation can be written as a weighted sum of changes in age-specific mortality rates, and a unique threshold age exists. The threshold for the coefficient of variation occurs later than that of its absolute counterpart, the standard deviation, a result verified for other pairs of relative and absolute indicators. Empirical applications show differing trajectories over time of the threshold age for different countries and different educational groups.

Conclusions: Change over time of the coefficient of variation can be expressed in a similar way to other indicators and provides a way to study the sensitivity of the indicator to changes in mortality. Although empirical applications show a similar trajectory for the threshold age of the coefficient of variation as for other indicators, the differences between them can be substantial.

Contribution: We formally determine the threshold age for the coefficient of variation and contextualize the sensitivities and threshold ages of lifespan inequality indicators.

Author's Affiliation

Other articles by the same author/authors in Demographic Research

Divergent trends in lifespan variation during mortality crises
Volume 46 - Article 11

Leveraging deep neural networks to estimate age-specific mortality from life expectancy at birth
Volume 47 - Article 8

Mexican mortality 1990‒2016: Comparison of unadjusted and adjusted estimates
Volume 44 - Article 30

Lexis fields
Volume 42 - Article 24

Geofaceting: Aligning small-multiples for regions in a spatially meaningful way
Volume 41 - Article 17

The threshold age of the lifetable entropy
Volume 41 - Article 4

Towards a Geography of Unmarried Cohabitation in the Americas
Volume 30 - Article 59

Most recent similar articles in Demographic Research

Ageing and diversity: Inequalities in longevity and health in low-mortality countries
Volume 50 - Article 12    | Keywords: aging, health, lifespan inequality, longevity, old-age threshold, regional differences, socioeconomic status

Longevity à la mode: A discretized derivative tests method for accurate estimation of the adult modal age at death
Volume 50 - Article 11    | Keywords: longevity, mathematical demography, modal age at death

The threshold age of the lifetable entropy
Volume 41 - Article 4    | Keywords: lifespan variation, mathematical demography, mortality, pace of aging

The sensitivity analysis of population projections
Volume 33 - Article 28    | Keywords: economic support ratio, elasticity, matrix calculus, matrix population models, population projections, sensitivity analysis, Spain

Reforging the Wedding Ring: Exploring a Semi-Artificial Model of Population for the United Kingdom with Gaussian process emulators
Volume 29 - Article 27    | Keywords: agent-based computational demography, Gaussian process emulator, multistate models, population dynamics, sensitivity analysis