Mortality modeling using probability distributions. APPLICATION in greek mortality data

Abstract

A number of different probability distributions describing age-specific mortality have been proposed. The most common ones, Gompertz and Gompertz - Makeham distributions have received wide acceptance and describe fairly well mortality data over a period of 60–70 years, but generally do not give the desired results for old and/or young ages. This paper proposes a new mathematical distribution (thereafter named ANBE), that results from the combination of the above distributions with Beta distribution. Beta distribution has been chosen for its flexibility to different dataset. Tested for its goodness of fit, ANBE shows a higher predictive ability for males and females, especially at higher ages. This new probability density function could also be applied in populations other than the Greek, subject to appropriate parameter detection (e.g. Maximum Likelihood). The application relies on mortality data collected and provided by ELSTAT for year 2011. Population data were used in order to calculate age and sex-specific mortality rates based on the estimated mean population of one-year interval age-group for the year concerned. According to our findings, the B.ANBE mortality model presents satisfactory results on appropriate evaluation criteria (AIC, BIC).