The opinion polling industry’s reputation has taken a battering in recent years, as high profile slip-ups in the US presidential election exposed frailties. So should we write them off? Not according to Economist data journalist G Elliot Morris, who’s written a book called Strength in Numbers: How Polls Work and Why We Need Them.

Presenter: Tim Harford
Producer: Jon Bithrey
Editor: Richard Vadon
Programme Coordinator: Brenda Brown
Sound Engineer: Rod Farquhar