The diaspora model for human migration

TL;DR

This paper introduces the diaspora model for human migration, emphasizing diaspora influence on migration flows and demonstrating its accuracy in reproducing observed migration patterns in Austria and the US.

Contribution

The paper presents a novel diaspora-based migration model that incorporates population heterogeneity and diaspora effects, improving understanding of migration flow heterogeneities.

Findings

Accurately reproduces migration flow and distribution in Austria and US.

Provides precise estimates of migrant inflow at multiple geographic scales.

Highlights the importance of diaspora in migration decision-making.

Abstract

Migration's impact spans various social dimensions, including demography, sustainability, politics, economy and gender disparities. Yet, the decision-making process behind migrants choosing their destination remains elusive. Existing models primarily rely on population size and travel distance to explain flow fluctuations, overlooking significant population heterogeneities. Paradoxically, migrants often travel long distances and to smaller destinations if their diaspora is present in those locations. To address this gap, we propose the diaspora model of migration, incorporating intensity (the number of people moving to a country) and assortativity (the destination within the country). Our model considers only the existing diaspora sizes in the destination country, influencing the probability of migrants selecting a specific residence. Despite its simplicity, our model accurately reproduces the observed stable flow and distribution of migration in Austria (postal code level) and US metropolitan areas, yielding precise estimates of migrant inflow at various geographic scales. Given the increase in international migrations due to recent natural and societal crises, this study enlightens our understanding of migration flow heterogeneities, helping design more inclusive, integrated cities.