The Roles of Social Networks

A substantial literature exists for both international and internal migrations, demonstrating a positive association between the likelihood an individual will migrate and the extent of any social network available to the potential migrant at destination. Several methodological limitations and alternative views on underlying mechanisms are drawn out in reviewing this literature with respect to rural-urban migration in this chapter. Fresh evidence is presented on a broad range of developing countries in light of these considerations, reaffirming a positive association though with a qualification; the causal association is much smaller than a simple correlation might suggest. An interesting branch of extant contributions has sought to disaggregate networks along various dimensions: for example, by gender, by migrant categories, by education level, and by diversity of location. New evidence is presented with respect to each of these dimensions, supporting some prior contentions, questioning others, and having implications for interpretations of mechanisms underlying network effects. Social networks at origin have been less-well examined but are also shown to be important in shaping migration propensities.