On the determination of sizes of markets

Summary

The number of specialized dealers is of interest to market research institutes. They need those market sizes to project sample results to the whole population of shops. A basis to get to know the size of such a population is given by address registers. These registers contain also dead addresses and they are incorrect as they do not contain all addresses of existing shops. We present an approach to deal with these two kinds of errors and derive an estimator with negligible bias.