Demografische modellen voor scenario-onderzoek

Abstract

A demographic model is described that has been used in scenario-research for calculating future population numbers. The demographic model developed is a discrete Markov-model. It calculates the changes in the Netherlands population numbers for each year successively. the model is specially developed to analyse the consequences of alternative assumptionswith respect to future death, birth, and migration developments. If necessary the model also makes use of administrative corrections. The results of the demographic model are compared with the known population numbers for the past. For the futre the results are compared with the projections published by the Netherlands Central Bureau of Statistics. the results of this extensive demographic model are also compared with those of some sparse models. These sparse models have a fewer number of transition probabilities between age classes to be estimated. It is concluded that the more extensive demographic models generally give better results than the sparse odels. These sparse models however give rather good results for general approximations when the heterogeneity within the age clases is modelled explicitly. The future population numbers for the oldest age group(s) are generally overestimated, presumably due to the effect of using the registration numbers in the models. For the CBS medium variant the calculated future population numbers differ less from the CBS population forecasts than for the low and high variant.<br>