A Comparative Study of Parametric Models of Old-Age Mortality

Four mortality models: Gompertz, Makeham, Logistic and Coale - Kisker models have been considered for a comparative study of Old- Age Mortality for both male and female based on reliable data of ten countries. Sufficiently long run of reliable data selecting from ten countries: Australia, Hong Kong, Canada, England, Israel, Japan, New Zealand, Poland, Singapore, United Kingdom have been used for this investigation. The main objective of this paper is to select the best fit mortality model from ages 85 onwards. Using the complete life table of ten different countries as input, the parameters of these mortality models have been estimated using Levenberg ? Marquardt iteration procedure. The estimated parameters of these models have been used for the testing the validity of the models which could be used for the projection of mortality rates at ages. Matlab version 7.11.0 has been used for the estimation of the parameters. It is observed from our result that among the four models the four parameter logistic model and three parameter Coale - Kisker give satisfactory results as the expected values are found to be very closed to observed data. The Gompertz model seems to be not suitable for prediction of old age mortality.