| Abstract: | The problems of statistics relating to international migration have been well documented. It is a fact that the concepts of legal nationality, residence, place of birth, time, and purpose of stay 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, but despite some encouraging developments, it is unlikely that homogeneity will be achieved during the rest of this century. This article analyzes how these 5 basic concepts are used to characterize migration. Statistical systems generally use at least 1 or more of these concepts to identify migrants from other international travelers. A review of these basic concepts reveals the great influence that legal or regulatory considerations exert, whether explicitly or implicitly, in their definitions. Perhaps one of the most serious problems in understanding how migration is viewed and measured by national statistical systems is to disentangle the legal or quasilegal nature of certain concepts from those that can be taken at face value. The tendency to sift from their meaning all legal impurities and thus transform them into reflections of actual events operates under the assumption that migrants are free agents, able to determine their durations of stay, absence, or the type of work that they will perform. In reality, the freedom of migrants stops where the State's prerogatives start, and statistics often reflect an uneasy compromise between the 2. Despite their many deficiencies, statistics on international migration are a rich source of information, not only about quantitative aspects of the process, but also about how the process is conceived by their generators. A careful evaluation of their meaning, scope, and limitations can be, therefore, a rewarding exercise. |
