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A team of researchers from the Institute for Cross-Disciplinary Physics and Complex Systems (UIB-CSIC) at Palma de Mallorca, Spain, and from the University of Marseille in France has developed the first international study on the hierarchy of cities using data from Twitter. The study has analyzed 21.017.892 geolocated tweets from 571.893 users during 1.000 days (from October 2010 until June 2013) in 58 cities among the 100 most populated in the world.

The objective of the study is to gain new insights in the debate on cities leadership taking into account human mobility. Analyzing geolocated tweets is possible to characterize how people moves after visiting a city, how a city attracts people from other places and what relationship the different cities have between themselves. This study bases the ranking of urban areas on the direct observation of mobility using Twitter, which is different from other classic studies based on geographical, economic, political influence, etc., factors.

In addition to being the first study of global scale using Twitter data to investigate the leadership of cities, it is the first study which has analyzed the global mobility (applied to the cities ranking) with direct data mobility and not indirect information.

According to the results, the researchers have concluded that Rome, Paris, Barcelona, Lisbon and Berlin (in this order) are the most attractive cities of the world (the ones that attract more visitors from other places). The world ranking of the most influential cities according to the issued tweets is: New York, London, Paris, Tokyo, and Singapore (Madrid is set to the 10th position and Barcelona in position number 11). At European level, the most influential cities are London, Paris, Moscow, Barcelona and Berlin. Residents making longest journeys from their cities depart from Moscow, Beijing, Petersburgo, Paris and Berlin; on the other hand, those who do more miles without being resident depart from Lisbon, Paris, Moscow, Rome and Istanbul.

In addition to the rankings, another interesting conclusion that emerges from the study is that the influence or attraction of cities is different according to the context of study. For example, Miami is the second most influential North American city in the world ranking, while if the mobility is restricted to the North America region alone, it falls to the 6th place in the ranking. In contrast, Detroit becomes the 5th most influent city in the North America ranking but it is the 8th among the American cities in the global arena.

The research was carried it out by Maxime Lenormand, Antònia Tugores, José. J. Ramasco, of IFISC, and Bruno Gonçalves, from the University of Marseille. It was published in the Royal Society Interface on July 15, 2015.

http://rsif.royalsocietypublishing.org/content/12/109/20150473