Lee-Carter mortality forecasting: a parallel generalized linear modelling approach for England and Wales mortality projections

The paper presents a reinterpretation of the model underpinning the Lee-Carter methodology for forecasting mortality (and other vital) rates. A parallel methodology based on generalized linear modelling is introduced. The use of residual plots is proposed for both methods to aid the assessment of the goodness of fit. The two methods are compared in terms of structure and assumptions. They are then compared through an analysis of the gender- and age-specific mortality rates for England and Wales over the period 1950-1998 and through a consideration of the forecasts generated by the two methods. The paper also compares different approaches to the forecasting of life expectancy and considers the effectiveness of the Coale-Guo method for extrapolating mortality rates to the oldest ages.