Understanding Internal Migration Through a Network Perspective [before doctoral defense]

Kivonat, rövid leírás

The main argument of this dissertation is simple: internal migration happens through a path-dependent network of flows, which has its own internal mechanisms, and every factor affecting migration is embedded in this flow structure. This notion is as old as migration research itself, but wide-spread contemporary models of internal migration do not account for it. They rely on modelling independent units, and independent dyads (bi-lateral flows), without a systematic framework. I argue that the application of new network science methods to empirical analysis can account for this simple and old notion, achieving systematic quantitative models of internal migration flow systems. The traces of network thinking were present since the very origin of migration research, in the groundbreaking works of Ernst Ravenstein, who built his model of internal migration in the United Kingdom on a system of currents between locations (Ravenstein 1885, 1889). His laws describe an interdependent system, in which each locality is influenced by other localities, and this influence itself is the core of explanation. His work aimed to explain relations, not the properties of individual places. Ravenstein's laws can easily be translated to a network model: localities are nodes, where agents reside, and the movement of agents produces the emergent macro-level structure of migration streams. Surprisingly, this systematic aspect of his work mostly disappeared during the 20th century – while some of his laws, one by one, laid the foundation for gravity thinking, the step-migration model, or ideas around migratory potential and counter-currents, the empirical tradition treated the individual locality, and later the individual dyad, as the base unit of analysis. Even today, more than a century later, migration researchers still return to Ravenstein as a kind of analytic null model (Rees and Lomax 2019, Macedo et al. 2020), but the systemic reading of his work remains rare. During the last century, only one large-scale migration theory emerged as both an extension and a critique of Ravenstein: the migration transition hypothesis developed by Zelinsky 1971. According to this model, migration patterns are directly influenced by the developmental stage of a society. Ravenstein described the era of the second industrial revolution, when centralization and urbanization moved migrants upwards the urban hierarchy. Zelinsky predicts that in post-industrial societies, a highly elaborated lattice of major and minor metropolises will define migration.