Smoothing of Two-Dimensional Demographic Data, Optionally Taking
into Account Period and Cohort Effects
Description
The implemented method uses for smoothing bivariate thin plate
splines, bivariate lasso-type regularization, and allows for both period
and cohort effects. Thus the mortality rates are modelled as the sum of four
components: a smooth bivariate function of age and time, smooth one-dimensional
cohort effects, smooth one-dimensional period effects and random errors.