Cities are so complex that we constantly build models to represent them, understand them and attempt to plan them. Models represent a middle ground between the singular configurations of cities and universal theories. This is what makes them valuable and prone to circulate (between places, institutions and languages) and evolve to adapt to new ideas, local conditions and/or other models. When it comes to analytical urban models (i.e. analytical representations of cities developed to study or simulate part of their structure or dynamics), there is a lack of academic understanding regarding how context and circulation affect their content, use and interpretation. What happens to analytical urban models and their reception during their circulation across geographical and disciplinary boundaries? How have different academic disciplines interacted with, contributed to and been influenced by analytical urban models? What are the consequences of urban models’ mobility for our understanding of cities? In this article, we employ the policy mobilities framework to analyse the circulation of analytical urban models. We use six canonical models as case studies to determine how their assumptions came about and how these models have circulated across different domains of policy and application by using biographical information and model analysis. The first contribution of the article is to demonstrate by example that our hypothesis regarding the influence of context is consistent. We also show that highly transferable/mobile models share common characteristics relating to contingent factors such as their creators’ biographies, institutional context and the traditional markers of power relations.@en

To reflect on the future of Environment and Planning B (EPB), I had to dig into its past. This is in part because the journal only entered my radar about a decade ago, when fellow PhD students from our Geodiversity project managed to publish an Agent-based Modelling (ABM) piece in the journal (Schmitt et al., 2015). The joy and pride of the team made me feel like this journal was a special place to have your research featured. With the online archive,1 I attempted to reconstruct how the journal and the field developed, how people predicted where we would be now. And I found just what I was looking for! Indeed, when you read Mike Batty’s (1998) editorial for the 25th anniversary, you are given a free tour of the story of EPB’s origin, from a spin-off of EPA to tackle the architectural scale of design at its beginnings under the editorship of Lionel March, to its later development as an outlet whose broader goal was, in a nutshell, to understand how cities work in order to make them better. The first 10 years of EPB illustrate the transition from a quarterly journal to an established publication for urban research, with more issues per year, more editors, in a publishing landscape divided, from 1983 to 2018, between Economy and Space (EPA), Design and Planning (EPB), Politics and Space (EPC) and Society and Space (EPD).2 In terms of content, the journal experienced a transition from theories of design to ‘formal languages for planning’ (Batty, 1998: 1). Although the journal is now operated in a collegial way, with a team of editors covering dedicated sections and leading special issues, the 1980s were a time of even more distributed leadership, with the majority of editorials actually written by guest editors. These guest editorials document the growing potential of computer usage in planning and design (e.g. Johnson, 1986; Stiny, 1986; Yeh, 1988) – an ‘unashamed’ transition of the journal’s scope (Batty, 1998).@en

This special issue of Environment and Planning B focuses on Spatial Inequalities and Cities. As the world progresses to almost a fully urban state, locations, networks, and access shape the everyday lives lived in cities, alongside being the movers and shapers of the future of sustainable and equitable urbanization. This special issue brings together a set of peer-reviewerd papers spanning urban science, urban analytics, geographic information / spatial science, network science, and quantitative socio-economic-spatial analysis, to explore and examine how the morphological, structural and spatial form of cities is linked to the production, maintenance and exacerbation of socio-economic inequalities and injustices. The issue also presents a critical angle on data, methods, and their use, and on how novel data and methods can help shed light on new dimensions of spatial inequalities. This editorial presents a brief critical review of the field of urban spatial inequalities and a summary of the special issue.

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Agent-based models (ABMs) are increasingly utilized in ecology and related fields, yet concerns persist regarding the lack of consideration for lessons learned from previous models. This study explores the potential of systematically conducted ABM reviews to contribute to cumulative science and theory development by synthesizing individual ABM findings more effectively. We are conducting a meta-review of ABM reviews to assess current practices, compare them to systematic literature review (SLR) literature recommendations, and evaluate their engagement with theory and theory development. Our analysis of the ecology and social science sample reveals that many reviews are not conducted systematically and lack transparency. The analysis step of SLRs holds significant potential to advance theory development. Reviews primarily focus on model design, while other avenues of theory development receive less attention. Our findings suggest ways to improve current practices and may guide future ABM reviews via benchmarks for methodological decisions and dimensions for advancing theory development.@en

Despite growing interest in the firm bargaining process, little research focuses on the structure of bargaining within multi-establishment firms. We question whether running negotiations at the workplace level and/or firm level is a strategic choice for employers. We hypothesize that the level chosen depends on the geography of the firm. Employers face a trade-off: workplace bargaining is more efficient because it meets local conditions; yet higher level negotiations increase coordination costs for workers and weakens their bargaining power, which can benefit the employer. Using a French representative survey, we find a significant relation between the level of bargaining within a firm and the number, spatial distribution and heterogeneity of its establishments, suggesting that the structure of multi-establishment firms can inform the level at which collective bargaining takes place.@en

Generative modelling entered the field of geography and spatial analysis some 35 years ago. Besides allowing spatial analysts and geographers to build operational models for transportation and planning, it has represented the opportunity to take causal inference from the traditional (statistical) analysis of empirical models to the design of causal mechanisms simulated in virtual environments. It is a major epistemological shift, whose scientific contribution still needs advocacy in the wider community of geographers and spatial analysts. In parallel, the expansion of both computing power and available data have made it easier for isolated teams and individuals to build ad hoc models fit for their specific research questions, leading to a cacophonous development of generative models unrelated to one another. Since the introduction of generative modelling in geography and spatial analysis, hundreds of models have been developed; all may have been wrong, but some were surely useful. However, most models built over the years have been abandoned, their program either inoperable with today’s technology or lost entirely. Over 35 years, this should strike us as vastly wasteful of ideas, time and energy. In this chapter, I will lay out possible paths towards sustainable, modular and painless generative models, and the expected impacts in terms of geographical theory development and scientific reproducibility. In this way, generative modelling done right can contribute both to a new form of causal inference and to the larger programme of social sciences: the simultaneous search for generalised explanations of social phenomena and recognition of the uniqueness of historical events.@en

Although gentrification and its associated changes in residential mobility have been widely studied, surprisingly little attention has been paid to the changing origin locations of gentrification-related residential moves. In this study, we use fine-grained register data from the Dutch Central Bureau of Statistics to uncover changing residential mobility patterns to and within the city of Rotterdam, the Netherlands. We identify that the state-led gentrification process goes hand in hand with the changing socioeconomic characteristics of in-movers and the changing origin locations of residential moves. The city of Rotterdam increasingly attracts middle- to high-income households from other core cities in the Netherlands, a process that we understand as inter-urban gentrification spillover. In parallel, intra-urban moves by economically vulnerable residents are declining, especially toward and within gentrifying neighborhoods. This represents evidence of exclusionary displacement. We conclude that the spillover effects of contemporary gentrification should be understood beyond an intra-urban metropolitan perspective since gentrification in one city can enhance gentrification in another.@en

Gentrification is a process whereby neighbourhoods and their socio-economic composition upgrade through residential moves and social mobility. Relatively little attention has been paid to the spatial aspect of gentrification-induced residential moves. This systematic literature review focuses on the origin and destination of moves to and from gentrifying neighbourhoods, by gentrifiers (movers in) and displacees (movers out). It identifies where, when, and how such research has been conducted and highlights gaps in the literature. Our results suggest that the destination of displaced households has been studied extensively, while an understanding of the spatial origins of gentrifiers is lacking. The few studies dedicated to gentrifiers' origins mostly focus on intra-urban environments, overlooking potential mobility dynamics from outside the city-region. We highlight that capturing both origins and destinations of movers at different spatial scales is necessary to demonstrate how residential mobility creates interactions and demographic interdependencies between neighbourhoods and cities.

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Cities have become the major habitat for human societies. They are also the places where the starkest social inequalities show up. Income, social, land and housing inequalities shape the built environment and living conditions of different neighborhoods of cities, and in return, unequal access to services, environmental quality and favorable health conditions in different neighborhoods and cities fuel the reproduction of interpersonal inequalities. This book examines how inequalities are produced and reproduced both within and between cities. In particular, we review land rent and social segregation theories from diverse disciplinary references and through examples taken from around the world. The attraction of urban centralities, which is further reinforced by the growing financialization of property and urban capital, is also analyzed through the lens of its influence on rent-seeking mechanisms and the ever increasing pressure of population migration.@en

In this article, I conduct a textual and contextual meta-analysis of the empirical literature on Zipf's law for cities. Combining citation network analysis and bibliometrics, this meta-analysis explores the link between publication bias and reporting bias in the multidisciplinary field of quantitative urban studies. To complement a set of metadata already available, I collect the full-texts and reference lists of 66 scientific articles published in English and construct similarity networks of the terms they use as well as of the references and disciplines they cite. I use these networks as explanatory variables in a model of the similarity network of the distribution of Zipf estimates reported in the 66 articles. I find that the proximity in words frequently used by authors correlates positively with their tendency to report similar values and dispersion of Zipf estimates. The reference framework of articles also plays a role, as articles which cite similar references tend to report similar average values of Zipf estimates. As a complement to previous meta-analyses, the present approach sheds light on the scientific text and context mobilized to report on city size distributions. It allows to identified gaps in the corpus and potentially overlooked articles. It confirms the relationship between publication and reporting biases.@en

La promotion de la négociation collective d’entreprise est au cœur des réformes successives du système français de relations professionnelles. L’objectif affiché est celui de l’instauration d’une régulation de proximité, permettant de construire des compromis efficaces entre la diversité des intérêts existant au sein de l’entreprise. Qu’en est-il en pratique ? Prenant appui sur une exploitation de l’enquête REPONSE (2017) appareillée à des données administratives sur l’implantation géographique des établissements issues de la base FLORES (2017), l’article montre que l’espace de la négociation collective se structure en quatre configurations et que la con10figuration de négociation la plus fréquente ne correspond pas à une régulation de proximité. Mobilisant des études de cas d’entreprise, nous montrons ensuite comment, derrière ces configurations, se jouent des rapports de forces entre les acteurs légaux de la négociation et comment leurs stratégies respectives contribuent à définir l’espace de négociation le plus propice à servir leurs intentions réciproques.@en

On the evening of 16th March 2020, the French president, Emmanuel Macron announced the start of a national lockdown, for a period of 15 days. It would be effective from noon the next day (17th March). On the 18th March 2020 at 01:11 pm, the first email circulated in the MicMac team, who had been working on the micro-macro modelling of the spread of a disease in a transportation network a few years. This email was the start of CoVprehension. After about a week of intense emulation, the website was launched, with three questions answered. A month later, there were about fifteen questions on the website, and the group was composed of nearly thirty members from French research institutions, in a varied pool of disciplines, all contributing as volunteers from their confined residence.@en

In this chapter, we discuss the emerging features of urbanisation in two BRICS countries (Russia and South Africa) by bringing together the different meanings of the concept of emergence in development economics and in complexity science. The objective of this cross-investigation is to identify the features of urban theories which only apply to the first industrialised countries (but do not apply to emerging powers such as the BRICS countries) and to identify the emerging patterns of growth and structure in urban systems deemed as extreme: e.g. the former Soviet Union and South Africa.@en

Although the cluster theory literature is bountiful in economics and regional science, there is still a lack of understanding of how the geographical scales of analysis (neighbourhood, city, region) relate to one another and impact the observed phenomenon, and to which extent the clusters are industrially coherent or geographically consistent. In this paper, we cluster spatial economic activities through a multi-scalar approach making use of percolation theory. We consider both the industrial similarity and the geographical proximity between firms, through their joint probability function which is constructed as a copula. This gives rise to an emergent nested hierarchy of geoindustrial clusters, which enables us to analyse the relationships between the different scales, and specific industrial sectors. Using longitudinal business microdata from the Office for National Statistics, we look at the evolution of clusters which spans from very local groups of businesses to the metropolitan level, in 2007 and in 2014, so that the changes stemming from the financial crisis can be observed.@en

The most recent English attempts at decentralisation take the shape of the city region devolution policy agenda. Decentralisation claims to empower localities and address regional growth imbalances, while creating a variety of new temporary and selective fiscal and geographic arrangements in policy-making that have the potential to create the opposite effect. This paper focuses on the relationship between decentralisation and territorial inequalities through the analysis of strategic discourse of six ‘devolved authorities’. A quantitative, qualitative, and comparative approach to this question complements the traditional insights obtained from in-depth case study analysis using actors’ interviews. It focuses on city regions’ official discourse of self-conceptualisation and marketization, and thereby highlights the wider policy and regional theory context of their production to frame the structural factors impacting the rewriting of city regional space. By doing so, we find a number of issues with the current decentralisation approach in competing priorities between localities, an over-reliance on agglomeration economies and urban competition, potential mismatches in scales of policy decision-making and delivery, and challenges regarding inequalities in a post-Brexit England.@en

Agglomeration economies are a persistent subject of debate in regional science and city planning. Their definition turns on whether or not larger cities are more efficient than smaller ones. Here, we complement existing discussions on agglomeration economies by providing a sensitivity analysis of estimated externalities to the definitions of urban agglomeration. We regress wages versus population and jobs over thousands of different definitions of cities in France, based on an algorithmic aggregation of spatial units. We also search for evidence of larger inequalities in larger cities. This paper therefore focuses on the spatial and economic complexity of the mechanisms defining agglomeration within and between cities.@en

Thanks to the use of geolocated big data in computational social science research, the spatial and temporal heterogeneity of human activities is increasingly being revealed. Paired with smaller and more traditional data, this opens new ways of understanding how people act and move, and how these movements crystallise into the structural patterns observed by censuses. In this article we explore the convergence between mobile phone data and more traditional socioeconomic data from the national census in French cities. We extract mobile phone indicators from six months worth of Call Detail Records (CDR) data, while census and administrative data are used to characterize the socioeconomic organisation of French cities. We address various definitions of cities and investigate how they impact the statistical relationships between mobile phone indicators, such as the number of calls or the entropy of visited cell towers, and measures of economic organisation based on census data, such as the level of deprivation, inequality and segregation. Our findings show that some mobile phone indicators relate significantly with different socioeconomic organisation of cities. However, we show that relations are sensitive to the way cities are defined and delineated. In several cases, changing the city delineation rule can change the significance and even the sign of the correlation. In general, cities delineated in a restricted way (central cores only) exhibit traces of human activity which are less related to their socioeconomic organisation than cities delineated as metropolitan areas and dispersed urban regions.@en

Bibliometrics have become commonplace and widely used by authors and journals to monitor, to evaluate and to identify their readership in an ever-increasingly publishing scientific world. This contribution introduces a multi-method corpus analysis tool, specifically conceived for scientific corpuses with spatialised content. We propose a dedicated interactive application that integrates three strategies for building semantic networks, using keywords (self-declared themes), citations (areas of research using the papers) and full-texts (themes derived from the words used in writing). The networks can be studied with respect to their temporal evolution as well as to their spatial expressions, by considering the countries studied in the papers under inquiry. The tool is applied as a proof-of-concept on the papers published in the online open access geography journal Cybergeo since its creation in 1996. Finally, we compare the three methods and conclude that their complementarity can help go beyond simple statistics to better understand the epistemological evolution of a scientific community and the readership target of the journal. Our tool can be applied by any journal on its own corpus, fostering thus open science and reflexivity.@en