Mobile tracking for 18 weeks

Study maps network of 7 million cell phone users from PhysOrg.com
Scientists have constructed a map of a societal communication network based on the mobile phone usage of 7 million individuals during a span of 18 weeks. As the first study to have access to a large amount of direct data of cell phone calls, the results show a counterintuitive requirement of weak ties rather than strong ties to maintain the integrity of a global network. In fact, the scientists found that removing these fragile weak ties can cause a global network to collapse.
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