Alessandro Vespignani, one of Dr Song’s colleagues at Northeastern, discussed what might be done with such knowledge. Dr Vespignani, another moonlighting physicist, studies epidemiology. He and his team have created a program called GLEAM (Global Epidemic and Mobility Model) that divides the world into hundreds of thousands of squares. It models travel patterns between these squares (busy roads, flight paths and so on) using equations based on data as various as international air links and school holidays.
The result is impressive. In 2009, for example, there was an outbreak of a strain of influenza called H1N1. GLEAM mimicked what actually happened with great fidelity. In most countries it calculated to within a week when the number of new infections peaked. In no case was the calculation out by more than a fortnight
Data from social networks are making social science more scientific (via @TheEconomist)