A study based on the analysis of mobile phone data reveals that residents of favelas in the city of São Paulo, Brazil, exhibit less variability in their daily travel patterns than residents of formal areas with similar incomes.
The study was published in the journal Transportation and was authored by Matheus Henrique Barboza from the Engineering School of the University of São Paulo (Poli-USP). Barboza’s work was supervised by Mariana Giannotti and co-authored by Anna Grigolon and Karst Geurs. The research is part of Barboza’s doctoral thesis developed through a dual-degree program between USP and the University of Twente in the Netherlands.
The analysis was based on 77 consecutive days of mobile phone records, totaling approximately 30 million events associated with around 6,000 users living in areas within or around São Paulo’s favelas. The study focused on intrapersonal mobility variability, or how much a person’s routes change from one workday to the next.
“Most transportation studies look at a single day in people’s lives. What we explored is the fact that phone data allows us to observe behavior over several weeks, something traditional research can’t capture,” Barboza explains.
The results show that income and living in a favela are not equivalent variables. Even after controlling for factors such as average income in the census tract, land use, employment density, and access to public transportation, the “favela” variable remained significant. In practical terms, this means that two people with similar incomes living in nearby areas may have different movement patterns simply because one of them lives in a favela.
According to Giannotti, the lower variability observed among favela residents should not be automatically interpreted as a sign of greater stability or choice. “An initial, generic hypothesis would be that favela residents face additional challenges compared to people with the same income who live in urban areas outside of favelas. Among these challenges, infrastructure bottlenecks related to mobility – such as narrow, steep alleys; distance to bus stops; and lack of adequate sidewalks – can impact access and consequently the variability of movement patterns,” she says.
The researchers used call detail records (CDRs), which are records of calls, messages, and internet connections automatically generated by cell phone operators. By identifying the antennas used over time, the researchers were able to reconstruct users’ daily movements and infer their places of residence based on their nighttime patterns.
They cross-referenced this information with data from the Demographic Census of the Brazilian Institute of Geography and Statistics (IBGE), land use databases from the City of São Paulo, and estimates of accessibility to jobs via public transportation. To measure mobility variability, the authors created a specific indicator: the total number of distinct locations among the three most frequent destinations each workday over four weeks.
Two results stand out. First, people with higher incomes tend to have less variability in their daily movements, indicating more stable routines. Second, favela residents also exhibited less variability despite being associated with more precarious economic conditions.
“Although informal workers tend to show greater variability because they work in multiple locations, living in a favela can impose additional limitations that reduce this fluctuation,” Barboza notes.
Giannotti points out that the data used in the study are from 2016 and cannot be directly extrapolated to the present. “It isn’t possible to extrapolate over time, especially considering the effects of the pandemic on people’s behavior. On the other hand, we understand that the results remain relevant from an analytical and conceptual point of view because the study investigates the mechanisms and structural relationships between mobility, income, informality, and residential status associated with more persistent characteristics of urban structures,” she says.
In addition to its academic contribution, the work has direct implications for urban planning and public policy formulation. “The research provides methods for exploring telephone data to support the development of Mobility Plans, which are mandatory for municipalities with more than 20,000 inhabitants according to the National Urban Mobility Policy,” Giannotti points out.
According to her, traditional origin and destination surveys are expensive and impractical for many municipalities. “If municipalities can advance in using this type of telephone and ticketing data for their plans, it’ll be a huge step forward in having public policies that are more data- and evidence-informed,” she says.
According to the researcher, analyses such as those carried out in the study can support policies such as ensuring adequate transportation in peripheral areas, designing fares and subsidies that align with work routines, and prioritizing infrastructure and service investments in areas with restricted daily mobility.
The data is anonymous and does not allow for direct identification of individuals. According to Barboza, access was obtained through a formal agreement with the operator. “We don’t have names, CPFs [ Brazilian taxpayer identification numbers ], or anything like that. What we were provided with were geographic coordinates, date, time, and an anonymized code that can’t be linked to personal information. But, of course, this is sensitive data, and therefore all use follows strict ethical protocols. The General Data Protection Law [ LGPD ] allows this type of research when conducted by universities and with anonymized data.”
The work was supported by FAPESP through a Doctoral Scholarship and a Research Internship Abroad Scholarship , both awarded to Barboza. It was also supported by a Research Grant to the Center for Metropolitan Studies ( CEM ), where Giannotti is one of the principal investigators. The CEM is one of FAPESP’s Research, Innovation, and Dissemination Centers ( RIDCs ).
About São Paulo Research Foundation (FAPESP)
The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe .
Transportation
Mobility variability of favela residents of São Paulo based on mobile phone data
27-Nov-2025