Digital footprints in the cityscape: 1 Finding networks of segregation through Big Data Vinicius M. Netto Maíra Pinheiro João Vitor Meirelles Henrique Leite 2 Abstract. Segregation has been one of the most persistent features of cities and therefore one of the main research topics in social studies. From a tradition that can be traced back to the Chicago School in the early 20th century, social segregation has been seen as the natural consequence of the social division of space, reducing segregation territorial segregation and taking the space as a substitute for social distance. We propose a change in the focus of static segregation of places to as social segregation is played by embodied urban trajectories. We analysed trajectories of groups of social actors differentiated by income levels in Rio de Janeiro, Brazil. Firstly, we used metadata from Twitter users moving around the city to derive geographic coordinates and timestamp of tweets, and identified users’ origins and destinations. Then we crossed information on trajectories with socioeconomic data in order to see potential social networks according to income, assess their spatial behaviour and potential spaces of social convergence – a geography of the segregative / integrative potential of encounters. This approach is intended to recast the spatiality of segregation potentially active in the circumstances of social contact in the city rather than in static territories and patterns of residential location. Key words: segregation, mobilities, social networks, Big Data. 1. Introduction: a new approach to urban segregation We will examine in this paper the relationship between forms of social segregation in the city and the mobilities of socially different actors. We suggest that the usual, purely spatial forms of segregation cannot explain the phenomenon of social segregation. Even if the answer to the question of the ways we experience social segregation still implies a role for space, we hope to show that this role cannot be reduced to territorial segregation. We will argue that, since our societies are highly mobile interaction systems, we need to see urban space beyond its seemingly static condition. Through a critique of usual approaches to segregation that have space as a reason and an explanation for social distance, we will emphasize the spatiality of our daily actions and urban encounters as main components of the experience and the phenomenon of segregation. In other words, in contrast to a literature traditionally focused on the territorial dimension, our approach reformulates the spatiality of segregation, showing ways in which segregation is shaped by the segregative / integrative potential of encounter. This shift represents a change of focus, from the vision of static forms of segregation inherent in places – where social distance is assumed, rather than understood in all its material manifestation – to the vision of social segregation reproduced through our actions and trajectories as urban actors. This reformulation of the spatiality of segregation should put the body, both the element that carries the signals of identities and personal differences, as the primordial instance where segregation is socially revealed and lived by the actor. In doing so, we intend to show that urban space maintains a key role in segregation – in 1 The title recalls Frederico de Holanda’s work “Class footprints in the landscape” (Holanda, 2000). 2 The authors are with Universidade Federal Fluminense (UFF), Escola Nacional de Ciência Estatística (ENCE), Universidade de São Paulo (USP) and Universidade Federal do Rio Grande do Sul (UFRGS) respectively. Email: v1n1netto@yahoo.co.uk