A visit to the International Festival of Statistics in Dublin (yes, really) prompted me to offer advice to young scholars on the interpretation and use of economic data.

Always ask yourself the question “where does that data come from?”. “Long distance rail travel in Britain is expected to increase by 96 per cent by 2043.” Note how the passive voice “is expected” avoids personal responsibility for this statement. Who expects this? And what is the basis of their expectation? For all I know, we might be using flying platforms in 2043, or be stranded at home by oil shortages: where did the authors acquire their insight?

“On average, men think about sex every seven seconds.” How did the researchers find this out? Did they ask men how often they thought about sex, or when they last thought about sex (3? seconds ago, on average)? Did they give their subjects a buzzer to press every time they thought about sex? How did they confirm the validity of the responses? Is it possible that someone just made this statement up, and it has been repeated without attribution ever since? Many of the numbers I hear at business conferences have that provenance.