How Rioters Act Like Shoppers

Shortly after the riots that spread across London in the summer of 2011, media outlets in the city began publishing maps trying to make sense of the event. They ran illustrations showing the sites of the worst rioting, as well as other maps cross-referencing the clusters of violence with the known home addresses – using court records – of people who’d been arrested in it.

At the time, these maps struck several researchers studying urban systems at University College London. “We thought, ‘this is a spatial system, and it looks a bit like something we have looked at before,’” says Toby Davies, one of the academics. He and his colleagues were picturing, more specifically, spatial models of how shoppers behave in search of retail. And this got them thinking. “It looks like retail," Davies says, "and retail is something we know we can model.” Why not try to mathematically model the movement of rioters?