This paper looks at data from 306 cities in China to identify trends in how different sizes and densities of cities relative to each other affect economic productivity. The interesting finding is that it is best to have either one big low-density city or many smaller high-density ones.
This article aims to assess the impacts of urban spatial structure on economic productivity. Drawing upon detailed gridded population data of 306 Chinese cities at the prefecture level and above, we identify their urban (sub)centers through exploratory spatial data analysis, construct indicators to measure their degrees of polycentricity and dispersion, and model the impacts of spatial structure on urban productivity. A regression analysis reveals that economic productivity is significantly associated with urban spatial structure. Conditioning on other factors, higher degrees of dispersion are associated with lower level of urban productivity whereas the effects of polycentricity depend on urban population density. Less densely populated cities are likely to have higher productivity levels when they are more monocentric, while urban productivity of cities with high population density tend to benefit from a more polycentric structure. The paper concludes with spatial planning implications.