THERE’S still time left. Time to buy a friend Michael Lewis’s Moneyball, that is. It’s an extraordinary true story of how a baseball side with little money became successful by using data. You should buy it even if you don’t know a thing about baseball. Many of the principles employed by Billy Beane, the general manager of the Oakland Athletics, apply equally well to football.

To give you a taste, I’d like to take just one of those. Beane was frustrated by his scouts selecting players who looked like stars, and ignoring those with better statistics who happened to look bad in designer jeans. So he replaced their judgment with a computer model.

Think we don’t make the same error as the scouts here? The work of the Fink Tank’s Dr Henry Stott and Matthew Atkinson on goalkeepers strongly suggests that we do.

Let’s take the case of John Filan, dropped by Wigan Athletic, after a terrible error against Arsenal, and Roy Carroll, replaced by Manchester United because of his reputation for howlers. Sound like good enough reasons to drop a goalkeeper? No, no, no.

What matters with a goalkeeper is how many goals they let in, not what it looks like when they do. The table with this column shows the number of shots on target necessary to get the ball past a particular goalkeeper. As can be seen, Filan tops the table by miles and Carroll is better than Edwin van der Sar, his replacement at United. Carroll’s figure is almost exactly the same as his average last season, incidentally.

So if Filan made a clownish error it may be not because he was bad, but because you get the ball past him only on the rare occasion when something goes wrong. It is horrifying that he was dropped for that — he is clearly one of the best goalkeepers in the country.

The Fink Tank also looked at the fatness of goalkeepers. Who would you select — a fat goalkeeper or a thin one? The data is surprising. Atkinson and Stott calculated the body mass index of Barclays Premiership goalkeepers and then related that to their performance. And it turns out fatter is better. It was also true that the fatter the goalkeeper, the larger the variation in ability. Maybe this is just coincidence, but Van der Sar is the thinnest Premiership goalkeeper and Carroll one of the fattest. Perhaps that’s why Sir Alex Ferguson made the swap: Van der Sar looks better in jeans. He certainly isn’t a better goalkeeper.