On the Morphology of a Growing City: A Heuristic Experiment Merging Static Economics with Dynamic Geography

Abstract

In this paper, we aim at exploring how individual location decisions affect the shape of a growing city and, more precisely, how they may add up to a configuration that diverges from equilibrium configurations formulated ex-ante. To do so, we provide a two-sector city model merging a static equilibrium analysis with agent-based simulations. Results show that under strong agglomeration effects, urban development is monotonic and ends up with circular, monocentric long-term configurations. For low agglomeration effects however, elongated and multicentric urban configurations may emerge. The occurrence and underlying dynamics of these configurations are also discussed regarding commuting costs and the distance-decay of agglomeration economies between firms. To sum up, our paper warns urban planning policy makers against the difference that may stand between appropriate long-term perspectives, represented here by analytic equilibrium configurations, and short-term urban configurations, simulated here by a multi-agent system.

Spatial Analysis Model for the Evaluation of the Territorial Adequacy of the Urban Process in Coastal Areas

“…The areas thus classified will be analysed to clarify the relationships between them, i.e., according to the way they are articulated in the territory (study of the structure, through their position). This will lead to the definition of the structure of territorial models and their functioning [36][37][38]. An attempt will be made to offer a synthetic vision of them and to explain the territorial aspects that underlie them through their fundamental components [39,40].…”

Residential income segregation: A behavioral model of the housing market

“…From a theoretical perspective, the residential income distribution has traditionally been studied using spatial equilibrium models ( Duranton and Puga, 2015;Fujita, 1989 ). These models assume that for each income group there exists a constant utility level across the city, and solve for the equilibrium prices yielding the same utility in each neighborhood.…”

“…In this situation we do not find that path dependency plays a significant role. Delloye et al (2015) also consider path dependency, but the shape of the city is determined by the strength of agglomeration economies. The ABMs in Delloye et al (2015) and Lemoy et al (2017) are specifically designed to potentially reach the equilibrium of spatial equilibrium models ( Fujita, 1989 ).…”

“…Delloye et al (2015) also consider path dependency, but the shape of the city is determined by the strength of agglomeration economies. The ABMs in Delloye et al (2015) and Lemoy et al (2017) are specifically designed to potentially reach the equilibrium of spatial equilibrium models ( Fujita, 1989 ). In our ABM we do not have this goal, and even when the system reaches a steady state (punctuated by noise) this is not an equilibrium in the typical sense of urban economics.…”