When was the last time you read a grand statement, accompanied by a large number, and wondered whether it could really be true? Statistics are vital in helping us tell stories – we see them in the papers, on social media, and we hear them used in everyday conversation – and yet we doubt them more than ever. But numbers – in the right hands – have the power to change the world for the better. If we are willing to let them, good statistics help us see things about the world around us and about ourselves – both large and small – that we would not be able to see in any other way.

Tim Harford takes us deep into the world of disinformation and obfuscation, bad research and misplaced motivation to find those priceless jewels of data and analysis that make communicating with numbers worthwhile. He reveals how we can evaluate the claims that surround us with confidence, curiosity and a healthy level of scepticism. And he shows us that if we think carefully about the way numbers are sourced and presented, we can look around us and see with crystal clarity how the world adds up.

How to Make the World Add Up: Ten Rules for Thinking Differently About Numbers is published by the Bridge Street Press. Buy your copy from our bookselling partners Waterstones.

In our ninth Festival of Economics, co-programmed by Diane Coyle and Richard Davies, economists and experts from around the world debate with each other – and their audiences – some of the key economic questions of our time.

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Festival of Economics: Tim Harford