The Development of the African System of Cities

Abstract

Sub-Saharan Africa has urbanised at tremendous speed over the last half century, in a process that has dramatically reshaped the economic and spatial profile of the region. Simultaneously, it has challenged much of the conventional empirical wisdom about how and why people move to cities. As we show in this article, the traditional view that countries urbanise alongside structural transformation is challenged in Africa, where urbanisation occurs despite low productivity in agriculture, very limited industrialisation, and a high share of primary sector employment across the urban hierarchy. There appear to be large household income gaps between urban and rural areas inducing migration, and these income premiums apply equally well to farm and non-farm families. Looking across the urban hierarchy, we also discuss how urban primacy can be problematic for economic growth in Africa, how secondary cities are lagging in industrial development, and how growth of employment in tradable services may signal a different path to structural transformation in Africa.JEL classifications: J00, J31, O13, O14, O18, O55, R00, R11.

Measuring Urban Economic Density

“…In column 2, settlement premiums in the two groups are similar (the average 34%); and, for cities, they have a non-monotonic pattern, ranging from 0.47 to 0.97 across the quartiles.Premiums are largest at the low and high-end sizes and are smallest for the 50-75th percentile group. This is similar to(Henderson and Kriticos, 2018) who argue that secondary cities such as in the 50-75th percentile have a role in the urban hierarchy which is limited by the lack of development of manufacturing. Below we will provide a somewhat different but not necessarily conflicting interpretation, as to why effects of population size are non-monotonic.In columns 3 and 4 we turn to individual wage income for the 19,938 people who work over 30 hours a week for just wages, with controls listed but including hours worked.…”

“…Our work is based on a set of developing countries in Africa where there is a literature focused on push-pull issues in the urbanisation process. These are reviewed in Henderson and Kriticos (2018) or Gollin et al (2016), with analysis of classical push arguments in Schultz et al (1968), Matsuyama (1992), Gollin et al (2007), and Bustos et al (2016) and an analysis of pull arguments in Lewis (1954), Hansen and Prescott (2002), and Galor and Mountford (2008). While we know climate deterioration or conflict may also push people into cities (Henderson et al (2017), Fay and Opal (1999), Barrios et al (2006), Brückner (2012)), we want to see if in Africa there is the appearance of strong income pull factors.…”

“…However, a key issue with the occupational data is that many people and even household heads do not report an occupation. Based on IPUMS data(Henderson and Kriticos, 2018), we believe…”

Urban Agglomerations and Employment Transitions in Ethiopia

“…While the population of Addis Ababa is by far the largest, its primacy rate (20 percent) is not so high as other African countries(Henderson and Kriticos 2018).…”

“…However, adding worker fixed e↵ects makes it possible to analyze agglomeration e↵ects only for movers. There is an argument that a pooled OLS works better when considering the net e↵ects of agglomeration (Henderson and Kriticos 2018;Roca and Puga 2017). In addition to including a host of observed worker and household characteristics to reduce the bias, we estimate the regression models for the subsample of non-migrants.…”