Harmonization by simulation : a contribution to comparable international migration statistics in Europe

International migration is a topical issue and of increasing concern to policymakers in Europe. An urgent need for reliable and comparable statistics led to a new EU regulation that obliges countries, starting from the reference year 2009, to supply migration statistics that comply with a harmonized definition. The countries may use modelling methods in order to meet these requirements. This book contributes to a more profound understanding of the effect of definitional variations on reported migration flow figures. It establishes a comprehensive and coherent framework for the harmonization of the data by using a general notion that all migration measures are manifestations of a common underlying relocation process. The instantaneous rate of relocation represents a basis from which figures on migration can be derived according to various definitions. The focus is on the duration of stay criterion, which constitutes the main source of discrepancies in the operationalization of the migration concept in the EU Member States. In the book, simulated mobility histories of individuals are used to derive various annual migration measures for the whole virtual population. A simulation approach, which gives complete control over the counting of predefined migration events, provides valuable insights into discrepancies between the country-to-country flow data produced by origin and destination countries. The sheer complexity of an origin-destination migration dynamics model that explicitly takes account of the observational plan is discussed. An assessment of the progress that has been made towards better comparability of migration flow statistics in the EU is presented that emphasizes the potential usefulness of modelling techniques for harmonizing the available data.