ABSTRACT
There is no such tiling as a net migrant (Rogers. 1990). Migration instead takes the form of gross migration flows - people moving from one place to another looking for new opportunities. Indeed, one of the fundamental laws of migration is that migration flows are bidirectional: '[e]ach main current of migration produces a compensating counter-current' (Ravenstein 1889). Nonetheless, neoclassical economic theories of migration generally focus on net migration as if migration streams were unidirectional. Net migration, the difference between immigration and emigration, is assumed to respond to differences in wages between regions and countries. Net migration is assumed to have effects on wage levels and per capita income. The neoclassical theory of migration should be treated with caution. It is based on an assumption of homogenous labour for which the attraction of a specific labour market is captured by the market wage. With homogenous labour, migration flows will only go one way. For what would be the reason for someone to move from a labour market with a high wage to a labour market with lower wages?
