Is the mortality convergence between East and West Germany a result of selection?

Robert Beise, Max Planck Institute for Demographic Research

Immediately after the unification East Germany experienced an unexpected large decline in mortality. Lagging behind West Germany for years, this gap has almost closed until today. Several factors were judged to be causal, but it is still unknown how much of the increase can be explained by them. This is especially true for the immediate changes. This paper will use the theory of unobserved heterogeneity as another possible part of the explanation, which has been ignored until now. The basis of this theory is the fact that every population is heterogeneous, some people are weaker than others. The frailer tend to die first, which results in a population compound by the stronger ones. Since the mortality in East Germany was higher, it is possible that the selection happened faster in East than in West Germany. The result would be a mortality convergence, as it was observed. By using a frailty model it is possible to take unobserved heterogeneity into account. First results suggest that the consequences of the selection are totally different for East and West Germany. While strong composition effects affect the mortality in East Germany and force a convergence of the overall mortality, for West Germany only slight selection effects were found.