Redrawing the map of Great Britain based on human interaction

CAMBRIDGE, Mass. A group of researchers at MIT, Cornell University and University College London have used one of the world's largest databases of telecommunications records to redraw the map of Great Britain. The research, which will be published in the journal PLoS ONE on Dec. 8, is based on the analysis of 12 billion anonymized records representing more than 95 percent of Great Britain's residential and business landlines. 'Since the pioneering work of Christaller and Lösch in the early 20th century, a long-standing question in economic geography has been how to define regions in space,' explains Carlo Ratti, director of the MIT Senseable City Lab and one of the paper's authors. 'Our paper proposes a novel, fine-grained approach to regional delineation, based on analyzing networks of billions of individual human transactions.' Given a geographical area and some measure of the strength of links between its inhabitants, the paper describes mathematically how to partition the area into smaller, non-overlapping regions while minimizing the disruption to each person's links. For the most part, the results of the partitioning correspond remarkably well with existing administrative regions, but they still unveil some unexpected spatial structures.