Faria, J. R. and Levy, Amnon, Illegal Immigration and Migrant Networks: Is There an Optimal Immigration Quota Policy?, Department of Economics, University of Wollongong, 2003.
High-skill immigrants form networks that facilitate subsequent low-skill immigration. To minimize the effects of low-skill immigration on unemployment, a strict lean-against-the-wind strategy or a flexible lean-against-the-wind strategy that is supported by, and takes into account the effect of, border control, are considered. None of these policies is necessarily better than the other as regards leniency toward low-skill immigration as well as the number of illegal immigrants. High-skill immigration increases illegal immigration when the effect of migrant networks on the supply of lowskill immigrants is greater than the job-creation effect of these networks.