How our world measures up More or Less: Behind the Stats

Why do we measure the world around us in the way we do? There is a rich history to be explored - from measuring the depth of the Nile in Ancient Egypt to the central role the French played in developing the metric system and the ultra-precise measurement systems we use today. Presenter Tim Harford is joined by journalist and author James Vincent to discuss the political, social and technological factors that have influenced how we size up our world.