The phantoms of historical family reconstitution: Estimating the population at risk in the historical Krummhoern (East Frisia, Germany) 1720 - 1874.

Josep Sottile Perez, deutsch
Kai Willführ, University of Oldenburg

Family reconstructions based on parish registers are widely used in historical demography. However, it is known that population size estimates based on parish registers might be significantly biased, because these commonly under register certain population groups, such as seasonal workers and labor migrants. For investigations which require estimation of the population at risk family reconstitution studies are therefore often of limited use. The extent of the bias deriving from under registration may vary from case to case. In this paper we quantify the magnitude of the under registration of the population using parish registers the historical Krummhörn region in East Frisia, Germany, from 1720 to 1874. We compare the census of 1871 by the Prussian authority with the population size estimates which we reconstructed from the family reconstitution study. The census of 1871 provides data on population size for every settlement in the Krummhörn region, but no information on age or gender distributions. Various methods are used to estimate the population size based on the family reconstitution data which differ regarding how cases are treated about whom no date of death or out-migration is known. The results indicate that up to 62% of the people who had been recorded in the census of 1871 had been also recorded by the pastors who were responsible for the parish registers. We find evidence that young unmarried adults were significantly underrepresented in the parish registers. Further research is conducted to investigate the extent of population-group differentials.

No extended abstract or paper available

 Presented in Session 9. Evaluating Data Quality I