In this paper, we aim to better understand how mixing in urban social networks is facilitated by commuting. Yet, how assortativity of commuting and social networks are related and how this relation is modified by the length of commute in cities is still largely uncovered. However, the assortativity of urban mobility is a universal feature across cities: individuals have been recently reported to visit locations that are similar to their home neighborhood 21, 23, 38, 39, 40.

Since the scale of socio-economic isolation greatly varies across cities 12, one may expect that the mobility of people also enables a different degree of social mixture. The spatial distribution of high versus low-income households determines the length of travel that can bridge disparate neighborhoods.

Meanwhile, the time to develop new social connections is especially limited for low-income workers who travel to work during rush hours 36, 37. Nevertheless, it is not trivial that long commutes should facilitate social inclusion, because social interactions might remain assortative even at places far from home 21, 23, 35. Due to spatial segregation, economically disparate neighborhoods tend to be far from each other 32, thus long commutes are more likely to link places with different social status 33, 34. Since aggregated social networks form spatially bounded communities across neighborhoods 17, the further one commutes, the higher the likelihood that commuting-related social connections will introduce diversity in the egocentric network of the commuter 30, 31. Yet, less is known whether mobility mixing has any imprint on the social connections of people.Д¬ommuting covers a large share of urban mobility 26 and by connecting home with work locations, the places where people spend most of their time, it plays an important role in the spatial formation of social connections 27, 28, 29. Given the importance of this problem, a growing community has investigated the patterns of mobility in cities to better understand mixing potentials across disparate and diverse neighborhoods 21, 22, 23, 24, which may increase economic prosperity 25. Furthermore, spatial segregation by income also fragments social networks, which can hinder progress and can deepen inequalities 16, 17, 18, 19, 20. However, cities are also known for high levels of segregation 8, 9, 10 where disparate neighborhoods are separated from each other in the urban space 11, 12, 13, 14, 15. Complex interaction networks of individuals in urban areas enabled by population density, co-location, and easy access together made cities the global engines of technological and economic progress 4, 5, 6, 7. Our results inform policy that facilitating access across distant neighborhoods can advance the social inclusion of low-income groups.Д¬ities are champions of diversity 1, 2, 3.

This suggests a universal relation between long-distance commutes and the integration of social networks. An above-median commuting distance in cities is linked to more diverse individual networks, moreover, we find that longer commutes are associated with a nearly uniform, moderate reduction of overall social tie assortativity across all cities. In this paper, we aim to better understand income sorting in social networks inside cities and investigate how commuting distance conditions the online social ties of Twitter users in the 50 largest metropolitan areas of the United States. Commuting facilitates the mixing of people from distant and diverse neighborhoods, but whether this has an imprint on social inclusion or instead, connections remain assortative is less explored. Millions commute to work every day in cities and interact with colleagues, partners, friends, and strangers.

Local number construct 3