Ralf is University professor, Chair holder of the Economic and Social Statistics department at the University in Trier. Papers on: survey sampling methods, data quality, computational statistics, indicator methodology and the modelling of imprecise data. Scientific coordinator and responsible for four work-packages of the DACSEIS project (Data Quality in Complex Surveys within the New European Information Society;. Scientific coordinator of the KEI (Knowledge Economy Indicators); Responsible for design and quality of the German SILC which includes the German Laeken indicators (two projects with the German Federal Statistical Office). Project coordinator of the Census 2011 project, which aims to develop the sampling and estimation methodology for the upcoming German census in 2011, as well as for the FP7 – AMELI project, which deals with the estimation of the European Laeken indicators based on the EU-SILC data. Partner in FP7 Blue-ETS project responsible for WP6 – Better Quality on Business data.