While traffic lights do use sensors to try and make slightly more intelligent decisions than perhaps they once did, they are still fairly dumb tools for regulating the flow of traffic. A recent Chinese study explores whether machine learning can do a better job. The Elephant & Castle roundabout near where I live is notorious for its complexity, with rush hour traffic bustling onto it from several directions. It's perhaps understandable therefore that humans struggle to program traffic lights to function effectively. Of course, automating the process is no mean feat either, both because it requires an accurate model of the traffic flow, and then the challenges inherent in optimizing the flow.