Working Paper: NBER ID: w30847
Authors: Yannay Spitzer; Ariell Zimran
Abstract: To explain the evolution of mass migration from Italy (1876--1920), we introduce the diffusion hypothesis, which augments traditional models of migration by allowing the spatial diffusion of migration over social networks in the country of origin. We test and validate the predictions of this theory using a new and comprehensive municipality- and district-level panel of emigration data over four decades. Italian migration began in a few separate epicenters from which it expanded gradually over time in an orderly spatial movement that dominated local push factors. While the main patterns that we document are parsimoniously explained by the diffusion hypothesis, they are difficult to rationalize by alternative theories. Confirming the diffusion hypothesis in the Italian case suggests that networks may be far more important than is commonly understood in shaping other movements of mass migration and may shape them in ways that have not previously been understood.
Keywords: mass migration; diffusion hypothesis; migration networks; Italy; emigration
JEL Codes: F22; J61; N33; N34
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| absence of networks (D85) | constrained emigration potential (F22) |
| expansion of networks (D85) | surge in migration (F22) |
| migration networks (J61) | migration rates (J61) |
| distance from epicenters (R12) | probability of mass emigration (J11) |
| migration of nearby municipalities (R23) | own emigration rates (J11) |