Seeing the Hidden Part of the Iceberg: Gauging the Real Dimension of International Migration

Abstract

The reliability and comparability of international migration statistics belong to the most important statistical issues due to the importance of correct dimensioning of the migration flows and stocks for effective and timely design of effective policy measures. This paper presents an assessment of the migration statistics provided by Eurostat, reveals the most prominent discrepancies between stock and flow data, prepares a summary of vital issues affecting both quality and completeness of the migration data, and identifies certain solutions in order to improve data comparability, reliability and completeness. There is no one-size-fits-all solution, but an eclectic mix which extends the use of administrative and private data, matches data coming from distinct sources, harmonizes the way in which data is compiled and reported by different countries, matches observed flows with (demographic) stock-based estimates, provides consistent estimates of the bilateral migration flows between countries, and improves the measurement of temporary and illegal/undeclared migration.

Keywords

• Official statistics methodology
• international migration
• migration measures
• data harmonization
• data dissemination