Dynamic models of residential segregation: brief review, analytical resolution and study of the introduction of coordination

In his 1971's Dynamic Models of Segregation paper, the economist Thomas C. Schelling showed that a small preference for one's neighbors to be of the same color could lead to total segregation, even if total segregation does not correspond to individual preferences and to a residential configuration maximizing the collective utility. The present work is aimed at deepening the understanding of the properties of dynamic models of segregation based on Schelling's hypotheses. Its main contributions are (i) to offer a comprehensive and up-to-date review of this family of models; (ii) to provide an analytical solution to the most general form of this model under rather general assumptions; to the best of our knowledge, such a solution did not exist so far; (iii) to analyse the effect of two devices aimed at decreasing segregation in such a model.Comment: 52 pages, 21 figures, working pape

Coûts environnementaux du développement périurbain : impact des configurations urbaines et des choix résidentiels

[Departement_IRSTEA]Territoires [TR1_IRSTEA]DTAM [Axe_IRSTEA]DTAM1-REPRO [Axe_IRSTEA]DTAM-QT1-INEGALITESCe projet de recherche part du constat que la littérature existante sur la durabilité des espaces périurbains n'a pas apporté de réponse sur deux points particuliers. En premier lieu, la question du transport est généralement considérée du seul point de vue du transport de personnes, dans une optique d'équilibre partiel dans laquelle le transport des biens produits et consommés dans la ville n'est pas pris en compte. Or la théorie économique récente, dans le cadre des modèles d'économie géographique, montre que la localisation des ménages est étroitement liée à celle des entreprises, et que les configurations existant à l'équilibre dépendent fortement des interrelations entre ces deux catégories d'agents économiques. En d'autres termes, s'il est indispensable de considérer les choix résidentiels des ménages pour analyser les flux de transport engendrés par ces derniers, il est tout aussi indispensable de tenir compte des conséquences de ces localisations résidentielles sur la localisation des entreprises, et aussi des effets en retour des localisations des entreprises sur la distribution spatiale des ménages. Cette question fait l'objet du premier axe de notre recherche. En second lieu, les travaux existants négligent en général le fait que les espaces périurbains accueillent des ménages de catégories sociales variées qui ont des comportements différents en termes de déplacement. Or, il semble important de proposer une analyse du développement périurbain intégrant la question du choix résidentiel des ménages en fonction de leur catégorie sociale, ceci afin de dresser des pistes d'évolution possible des flux de transport engendrés par les espaces périurbains. C'est ce qui est développé dans le second axe de notre recherche. Enfin, ces analyses portant sur la localisation résidentielle des différentes catégories socio-professionnelles nous amènent aussi à analyser la ségrégation résidentielle dans les zones périurbaines, en lien avec les déterminants des choix de localisation résidentielle des ménages. / This research starts from the premise that the existing literature on the sustainability of suburban areas has not provided answers to two specific points. Firstly, the issue of transport is generally considered from the point of view of the transport of persons, in a partial equilibrium framework in which the transport of goods produced and consumed in the city is not taken into account. But the recent economic theory, with the new economic geography models, shows that the location of households is closely linked to the location of firms, and that the existing equilibrium configurations depend strongly on the interrelationships between these two categories of agent. In other words, it is essential to consider the residential choices of households to analyze the traffic flows they generate, but it is also necessary to take into account the consequences of these residential locations on the location of firms and the feedback effects of corporate locations on the spatial distribution of households. This question is the subject of the first axis of our research. Second, existing studies generally neglect the fact that the suburban areas host various social groups of households that have different behaviors in terms of mobility. However, it seems important to provide an analysis of suburban development incorporating the issue of residential choices of households according to their social class, in order to establish avenues for possible evolution of transport flows generated by the suburban areas. This is what is developed in the second focus of our research. Finally, the residential location of the different socio-professional categories is also analyzed in terms of urban segregation, in relation with the determinants of households’ choices

Socio-economic utility and chemical potential

In statistical physics, the conservation of particle number results in the equalization of the chemical potential throughout a system at equilibrium. In contrast, the homogeneity of utility in socio-economic models is usually thought to rely on the competition between individuals, leading to Nash equilibrium. We show that both views can be reconciled by introducing a notion of chemical potential in a wide class of socio-economic models, and by relating it in a direct way to the equilibrium value of the utility. This approach also allows the dependence of utility across the system to be determined when agents take decisions in a probabilistic way. Numerical simulations of a urban economic model also suggest that our result is valid beyond the initially considered class of solvable models.Comment: 6 pages, 3 figures, final versio

Urban environmental quality in two Belgian cities, evaluated on the basis of residential choices and GIS data

Our objective in this paper is to analyse empirically the effects of environmental quality on residential location choices in two Belgian cities, using a detailed description of the urban environment derived from remotely sensed data and using GIS tools. According to urban models which include amenities, environmental quality may influence land rents and location by income in the city. In order to test these relations, average land rents and mean income per district are regressed on distance to the centre and several environmental characteristics, using the instrumental variables method in order to take account of endogeneity. Fourteen environmental variables, representing socioeconomic facilities and natural attributes are obtained from aerial photographs, satellite images, and ancillary data. Their spatial representations are constructed using GIS functions. The empirical results confirm the impact of greenery on location choice and the existence of a higher environmental quality at the periphery than near the centre of the two cities. They also reveal that the impact of environmental quality components on residential location depends on the shape and history of the cities and on the relative scarcity of the environmental attributes

Agglomeration economies and spatial configurations in rural areas

The question to be addressed in this paper is that of the agglomeration and dispersion forces that are likely to account for the location of people and jobs in rural areas and the way these forces explain spatial patterns in rural areas depending on urban influence. Economic geography models may provide suitable tools with which to investigate the organization of rural areas. We first review these models, focusing on dispersion forces, which rest on land consumption and transport costs. We then suggest a set of hypotheses concerning the main forces at work in rural areas. Intensity of agglomeration economies is hypothesized to be related to urban size, which in turn induces increasing land rents and finally agglomeration diseconomies. Such diseconomies encourage population spread around the city and in a second stage a possible partial decentralization of population-serving firms, which seek proximity to households because of shopping transport costs. The consequences in terms of spatial patterns are that beyond a certain threshold of city size, decentralization of population-serving firms occurs, giving rise to secondary service centers, whereas services remain concentrated in the center for smaller cities. Empirical results concerning population densities, labor-force exchanges, and distribution of residentiary services in labor-market areas surrounding cities in six French regions are presented.

Does public housing occupancy increase unemployment?

International audienceThis paper shows that living in public housing has no effect on the probability of being unemployed in France, once we account for the endogeneity of public housing. We estimate a simultaneous probit model of unemployment and public housing. On a first sample for Lyon, we instrument public housing with the gender composition of children. On a second national sample, the instrument is the city-level share of public housing. Both samples yield the same conclusion, which we justify by showing that a small amount of selection on unobservables is enough to eliminate the positive effect found in “naive” estimates

Coûts environnementaux du développement périurbain : impact des configurations urbaines et des choix résidentiels

[Departement_IRSTEA]Territoires [TR1_IRSTEA]DTAM [Axe_IRSTEA]DTAM1-REPRO [Axe_IRSTEA]DTAM-QT1-INEGALITESCe projet de recherche part du constat que la littérature existante sur la durabilité des espaces périurbains n'a pas apporté de réponse sur deux points particuliers. En premier lieu, la question du transport est généralement considérée du seul point de vue du transport de personnes, dans une optique d'équilibre partiel dans laquelle le transport des biens produits et consommés dans la ville n'est pas pris en compte. Or la théorie économique récente, dans le cadre des modèles d'économie géographique, montre que la localisation des ménages est étroitement liée à celle des entreprises, et que les configurations existant à l'équilibre dépendent fortement des interrelations entre ces deux catégories d'agents économiques. En d'autres termes, s'il est indispensable de considérer les choix résidentiels des ménages pour analyser les flux de transport engendrés par ces derniers, il est tout aussi indispensable de tenir compte des conséquences de ces localisations résidentielles sur la localisation des entreprises, et aussi des effets en retour des localisations des entreprises sur la distribution spatiale des ménages. Cette question fait l'objet du premier axe de notre recherche. En second lieu, les travaux existants négligent en général le fait que les espaces périurbains accueillent des ménages de catégories sociales variées qui ont des comportements différents en termes de déplacement. Or, il semble important de proposer une analyse du développement périurbain intégrant la question du choix résidentiel des ménages en fonction de leur catégorie sociale, ceci afin de dresser des pistes d'évolution possible des flux de transport engendrés par les espaces périurbains. C'est ce qui est développé dans le second axe de notre recherche. Enfin, ces analyses portant sur la localisation résidentielle des différentes catégories socio-professionnelles nous amènent aussi à analyser la ségrégation résidentielle dans les zones périurbaines, en lien avec les déterminants des choix de localisation résidentielle des ménages. / This research starts from the premise that the existing literature on the sustainability of suburban areas has not provided answers to two specific points. Firstly, the issue of transport is generally considered from the point of view of the transport of persons, in a partial equilibrium framework in which the transport of goods produced and consumed in the city is not taken into account. But the recent economic theory, with the new economic geography models, shows that the location of households is closely linked to the location of firms, and that the existing equilibrium configurations depend strongly on the interrelationships between these two categories of agent. In other words, it is essential to consider the residential choices of households to analyze the traffic flows they generate, but it is also necessary to take into account the consequences of these residential locations on the location of firms and the feedback effects of corporate locations on the spatial distribution of households. This question is the subject of the first axis of our research. Second, existing studies generally neglect the fact that the suburban areas host various social groups of households that have different behaviors in terms of mobility. However, it seems important to provide an analysis of suburban development incorporating the issue of residential choices of households according to their social class, in order to establish avenues for possible evolution of transport flows generated by the suburban areas. This is what is developed in the second focus of our research. Finally, the residential location of the different socio-professional categories is also analyzed in terms of urban segregation, in relation with the determinants of households’ choices