The gompertz force of mortality in terms of the modal age at death

Trifon I. Missov, Adam Lenart, Laszlo Nemeth, Vladimir Canudas-Romo, James W. Vaupel

Research output: Contribution to journalArticle

Abstract

Background: The Gompertz force of mortality (hazard function) is usually expressed in terms of a, the initial level of mortality, and b, the rate at which mortality increases with age. OBJECTIVE We express the Gompertz force of mortality in terms of b and the old-age modal age at death M, and present similar relationships for other widely-used mortality models. Our objective is to explain the advantages of using the parameterization in terms of M. Methods: Using relationships among life table functions at the modal age at death, we express the Gompertz force of mortality as a function of the old-age mode. We estimate the correlation between the estimators of old (a and b) and new (M and b) parameters from simulated data. RESULTS When the Gompertz parameters are statistically estimated from simulated data, the correlation between estimated values of b and M is much less than the correlation between estimated values of a and b. For the populations in the Human Mortality Database, there is a negative association between a and b and a positive association between M and b.

Original languageEnglish (US)
Pages (from-to)1031-1048
Number of pages18
JournalDemographic Research
Volume32
Issue number1
DOIs
StatePublished - 2015
Externally publishedYes

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ASJC Scopus subject areas

  • Demography

Cite this

Missov, T. I., Lenart, A., Nemeth, L., Canudas-Romo, V., & Vaupel, J. W. (2015). The gompertz force of mortality in terms of the modal age at death. Demographic Research, 32(1), 1031-1048. https://doi.org/10.4054/DemRes.2015.32.36