The Concept of International Migration as Reflected in Data Collection Systems 1

Abstract

The problems of statistics relating to international migration have been well documented. ³ It is an established fact that the concepts underlying those statistics vary considerably, not only between countries but even within countries through time or between different sources of information within the same country. The crusade to achieve greater homogeneity in the concepts underlying flow statistics on international migration was started at least 55 years ago ⁴ , but despite some encouraging developments, it is unlikely that homogeneity will be achieved during the rest of this century. It is important, therefore, to focus attention on the concepts of international migration being used today in statistical systems to identify their points of similarity, the main sources of variation, and the strengths and weaknesses that different characterizations of international migrants may have from a data collection perspective.