Revisiting the urbanization curve: Fid-Bau Portal

Revisiting the urbanization curve

Mulligan, Gordon F.

Highlights • Urbanization continues to be widely studied in the spatial and regional sciences. • The S-shaped urbanization curve, ideally comprised of three stages, can be depicted by the logistic process. • Linear regression is used to estimate both nation-specific and cross-national (pooled) urbanization curves. • Multivariate, cross-national urbanization curves are examined both in the recent and the more distant past. • Nations sharing similar urbanization experiences are clustered together and separate urbanization clubs are formed.

Abstract The urbanization process creates demographic landscapes that are both volatile and uneven. As regions or nations pursue economic development, the level of urbanization—the percentage share of people living in cities—follows a typical pattern: urban shares first rise slowly, then rapidly, and then slowly again. The entire sequence traces out an S-shaped figure often called the urbanization curve. This curve has been widely invoked in the discussion of Homo Urbanus but has rarely been used to analyze the urbanization experiences of different regions and nations. This paper revisits the urbanization curve and shows that national urbanization—whether contemporary or historical—generally conforms to the logistic process. Using UN population data, comparisons are made between the logistic model and other simple time-series and econometric models. The logistic process is sufficiently flexible to depict urbanization unfolding across nations at very different stages of economic development. The substantial variety now seen in national urbanization suggests the existence of separate urbanization clubs.