Relations between measurements of iInternational migration statistics
Beata Nowok, Central European Forum for Migration Research (CEFMR), Poland
The aim of this presentation is to provide a comparative analysis of various measurements of international migration flows and to relate each measurement to the others. The comparisons refer to measurements produced based on the same or various sources. They focus on the crucial distinction between migrants (transition approach) and migration (movement approach). Besides, a great importance is attached to different time aspects, for example: duration of stay criterion used in the definition of migrant and migration, the concept of the intended and actual duration of stay, date of registration of migrations and date when they are included in the statistics. The use of latest migration and n-year-ago migration data, which are usually collected in surveys and censuses, is discussed. Issue and expiry of residence permits are contrasted with immigration of foreigners and emigration of foreigners respectively. A widely used method of calculating net migration based on balance equation is compared with the net migration measured as a difference between immigration and emigration. The analysis assesses the adequacy of various measurements and gives insights into the sources of discrepancies in statistics on migration flows between pairs of countries, which are produced by the countries of origin and destination respectively.