Why people emigrate

Semi-regular blogging service resumes this week with a few posts on migration - still a very topical issue on both sides of the Atlantic.

The first paper I'd like to highlight is by the University of Chicago's Jeffrey Grogger, and UCSD's Gordon H. Hanson. Their recent NBER Working Paper No. 13821, Income Maximization and the Selection and Sorting of International Migrants, seeks to explain to what extent selection and sorting account for international migration flows using data on emigrant stocks by schooling level and source country in OECD destinations. As the authors conclude, a simple model can explain a lot:

Two dominant features of international labor movements are positive selection of individuals into migration and positive sorting of migrants across destinations. We show that a simple model of income maximization can account for both phenomena.

The more educated are more likely to emigrate; and more-educated migrants are more likely to settle in destination countries with higher rewards to skill. As the authors explain:

In our selection regression, we find that migrants for a source-destination pair are more educated relative to non-migrants, the larger is the skill-related difference in earnings between the destination country and the source. That is, positive selectivity is stronger where the reward to skill in the destination is relatively large. This result obtains for wage differences expressed in levels, but not in logs.

...Positive sorting is a general prediction of income maximization. In our sorting regression, the relative stock of more-educated migrants in a destination is increasing in the level earnings difference between high and low-skilled workers. This correlation is stronger when wage differences are adjusted for taxes, implying that migrants weigh post-tax earnings when choosing a destination. The U.S. and Canada enjoy relatively large post-tax skill-related wage differences, which largely account for their ability to attract more educated migrants relative to other OECD countries.

Other factors are also at work:

Our analysis also shows that language, history, and policy affect migration. English-speaking destinations draw higher-skilled immigrants than other destinations, whereas former colonial powers draw lower-skilled immigrants from their former colonies than from other source countries. Destinations with liberal refugee and asylum policies draw relatively low-skilled immigrants, all else equal.

An ungated version of the paper is available here or here.