Fernando Sanz-Gracia

The validity of the monocentric city model in a polycentric age: US metropolitan areas in 1990, 2000 and 2010

In this article, we use local indicators of spatial association (LISA) and other spatial analysis techniques to analyze the distribution of centers with high employment density within metropolitan areas. We examine the 359 metropolitan areas across the United States at three points in time (1990, 2000, and 2010) to provide a spatio-temporal panoramic of urban spatial structure. Our analysis highlights three key findings. (1) The monocentric structure persists in a majority of metropolitan areas: 56.5% in 1990, 64.1% in 2000, and 57.7% in 2010. (2) The pattern of employment centers remains stable for most metropolitan areas: the number of centers remained the same for 74.9% of metropolitan areas between 1990 and 2000 and for 85.2% between 2000 and 2010. (3) Compared with monocentric metropolitan areas, polycentric metros are larger and more dense, with higher per-capita incomes and lower poverty rates.

The accuracy of graphs to describe size distributions

This article analyses the performance of the graphs traditionally used to study size distributions: histograms, Zipf plots (double logarithmic graphs of rank compared to size) and plotted cumulative density functions. A lognormal distribution is fitted to urban data from three countries (the United States, Spain and Italy) over all of the twentieth century. We explain the advantages and disadvantages associated with these graphic methods and derive some statistical properties.

The Size Distribution of Employment Centers within the US Metropolitan Areas

This study tackles the description of the size distribution of urban employment centers or, in other words, the size of areas within cities with significantly high densities of workers. Certainly, there exists a branch of urban economics that has paid substantial attention to urban employment centers, but the efforts have been focused on identification methodologies. In this paper we build on such body of research and combine it with insights from the latest contributions in the sister subfield of city size distributions to push the agenda forward in terms of the understanding of these phenomena. We consider the 359 Metropolitan Statistical Areas (MSAs) in the United States in the year 2000 and reach three main conclusions: First, employment center sizes are more unevenly distributed than city sizes; second, the two functions that best describe city size distributions, namely the lognormal and the double Pareto-lognormal, also offer a good fit for the case of centers, particularly the latter; and third, several interesting statistically significant relationships (correlations) between variables related to centers and MSAs are deduced. Further experiments with a different technique of center identification suggest that the results are fairly robust to the method of choice.

The demographic impact of terrorism: evidence from municipalities in the Basque Country and Navarre

ABSTRACT This paper studies the persistence of the effects of terrorist attacks on the urban structure at the regional level. With this aim, a dynamic differences-in-differences approach is applied to all the municipalities of the Basque Country and Navarre autonomous communities in Spain during the period 1986–2014. The results show that terrorism had a negative and transitory effect on population growth. We also find that incidents with deaths implied more adverse shocks. Terrorist attacks had more significant effects in bigger municipalities and in the provinces with a stronger ideological polarization. Finally, we provide evidence of demographic spatial effects derived from violence.