Even in large cities, we build tightly-knit communities


A study of group clustering--do your friends know each other?--shows that it does not change with city size. [via Flowing Data]

Social networks derived from mobile phone data in Portugal: An average urban dweller of Lisbon has approximately twice as many contacts than an average individual in the rural town of Lixa. However, the odds that an individual's contacts mutually know one another remains largely constant. ...

There is an important difference, though: if in a real village our connections might simply be defined by proximity, in a large city we can elect a community based on any number of factors, from affinity to interest to sexual preference.

The findings of this research help elucidate the role of cities as accelerators of human interactions, and the effectiveness of urban social space in the diffusion of ideas and information. Eventually, they can help us understand a broader spectrum of social phenomena, from crime to the spread of diseases.

02Illustration: Kael Greco, MIT Senseable City Lab