Does the monocentric model work in a polycentric urban system? An examination of German metropolitan regions

Abstract: https://journals.sagepub.com/doi/full/10.1177/0042098020912980#abstract

One of the most durable economic models of urban growth is the traditional monocentric (or “Alonso-Mills-Muth”) model that posits that urban spatial structure is a function of wealth, transportation costs, land rents, and population. However much of the empirical work has been focused on US cities and metropolitan areas. This paper contributes to this discussion by testing the viability of the monocentric model when applied to metropolitan areas in Germany. In doing so, we assume there are sufficient unique characteristics of German metropolitan urbanisation, including the role of historical geography, the polycentric nature of the metropolitan growth, the role of land market regulations, and systemic urban shrinkage to warrant different specifications and outcomes of the monocentric model.

We estimate the model with a unique dataset covering 92 metropolitan areas over two time periods (2000 and 2014), which allows estimation in both a cross-sectional and a panel framework, using spatial regression techniques. We found that similar to the US studies, the model performed reasonably well, particularly with the overall fit and the performance of the population variable, which was significant and positively related to urbanised area. Personal income and land prices showed mixed results and the coefficients for transportation costs proved to be challenging. We also found that regional geography matters: a region in eastern Germany is smaller than one in the west. A proxy variable for regional polycentricity was not significant. Finally, we found that the model’s behaviour differs between growing and shrinking regions, most notably in the differing impacts that population change has on the change in urbanised area.

Despite the focus on German metropolitan areas, this paper is of interest to a broader international audience for a number of reasons. First, we contribute to the international comparative literature on the drivers of land use change and expand the geographic scope of the monocentric model by empirically validating the model using a unique dataset from Germany described above. Second, we contribute to the methodological development of the model by addressing issues of spatial autocorrelation through the specification of a spatial error model. Finally, we test a number of empirical hypotheses which will be of interest to those interested in the drivers of urban spatial structure more broadly, in particular the role of polycentricity and urban shrinkage in determining urban spatial form.

Read the accompanying article on Urban Studies OnlineFirst: https://journals.sagepub.com/doi/full/10.1177/0042098020912980