Measuring the importance of age

Annette Baudisch, Max-Planck Odense Center on the Biodemography of Aging
Marcus Ebeling, Universität Rostock

Comparing populations is greatly facilitated by means of simple indices that can readily be calculated for populations with different characteristics. Deriving such indices, we suggest an intuitive method to quantify the impact of age on mortality, where age-dependence can follow any general pattern. The method only requires estimating the constant, age-independent mortality component. Using the constant mortality scenario as baseline, we derive two age-indices that quantify the importance of age. The indices provide a complementary and connected perspective, where both indices can be viewed as two sides of the same coin. We illustrate the workings and utility of the method with various examples. The indices are envisioned to reveal general trends and regularities that may not be (as) apparent from common perspectives. We believe that the method presented here may prove useful, since it is simple, intuitive and closely related to the recently developed pace-shape framework, a new perspective which is starting to reveal interesting results in comparative studies.