[Who is a migrant? Problems of documenting and defining spatial mobility in developing countries].

"Increasingly uneven spatial population distribution, especially in developing countries, has brought about a growing need for better statistical information on the extent of the various forms of spatial mobility during the [1980s] and their determinants and consequences....The main issues discussed in this paper are...the problems of defining and measuring spatial mobility in general as well as [reviewing] the types of mobility-related questions in censuses, their strengths and weaknesses, and the possibilities of evaluation of the collected data. Finally, alternative concepts for measuring spatial mobility are discussed which could help to gather information on non-permanent forms of spatial mobility, an issue of growing importance for the developing world." (SUMMARY IN ENG)