Internal migration and population redistribution: a cross-national comparison

Marek Kupiszewski, Institute of Geography and Spatial Organization PAS
Dorota Kupiszewska, International Organization for Migration (IOM)
Martin Bell, University of Queensland
Elin Charles-Edwards, University of Queensland
Philipp Ueffing, University of Queensland
John Stillwell, University of Leeds
Konstantinos Daras, University of Leeds

An important and long-standing question in population geography concerns the role of migration in regional population dynamics, particularly population concentration and de-concentration, and the way in which this evolves over time. While theoretical models suggest progressive evolution, few countries measure urban-rural migration directly and comparisons are hindered by cross-national differences in data types, definitions and territorial divisions. This paper utilises data from the IMAGE project database, a global repository of internal migration data collections, coupled with the IMAGE Suite, a bespoke software system which computes key migration indicators based on flexible geographies, to explore both the methodological and substantive dimensions of this problem. We focus on a sample of countries representing all continents for which high resolution migration data are available and show how differences in spatial resolution affect key measures of migration impact including the crude migration intensity (CMI), the migration efficiency index (MEI) and the aggregate net migration rate (ANMR). We then use population density as a proxy for level of urbanization and examine cross-national differences in its relationship with regional net migration rates. Migration events and fixed interval transitions reveal contemporary trends while lifetime migration data suggest long-term effects. Results show that the relative contributions of intensity and efficiency vary widely between countries, that migration efficiency is largely insensitive to the modifiable areal unit problem, and that the impact of migration on population redistribution varies widely between countries around the world.