DeRaS (Death Rates Simulation) is a new software tool designed for an efficient life table construction under several detailed conditions defined by the user.
DeRaS is useful for all who need to quickly and efficiently construct one, two, ten or even up to hundreds of life tables for more populations and/or who want to use different methods of mortality data smoothing and extrapolating.
DeRaS offers several smoothing and extrapolating methods of empirical mortality rates or probabilities of dying at higher ages. There are six generally recognized mortality models included in the application – Gompertz and Gompertz-Makeham as two representatives of exponential functions, two logistic functions (Kannisto and Thatcher with constant) and two less frequently used models (Coale-Kisker, Heligman-Pollard).
Unknown parameters are estimated through a nonlinear regression procedure using iteratively reweighted least squares. Weights enable to eliminate heteroskedasticity in data.
All available data from the Human Mortality Database were employed for testing this application.