Nigel Hawkes is the editor of Straight Statistics. This article was originally published on StraightStatistics.org
The Guardian's Readers' Editor conceded last week that the paper is not too good with numbers.
Chris Elliott quotes from a reader's letter suggesting there is a cultural problem with numbers among Guardian journalists, citing two corrections published a week ago — one about new floor space planned by big food retailers, the second about emigration from Greece.
Both of these errors produced conclusions implausible enough that you might hope somebody — author, section editor, or sub-editor — would have spotted them. One suggested that big food retailers in Britain had permission for another 16,000 new supermarkets (the correct figure was 1,600) and the other that 1.21 million people had emigrated from Greece in 2010, 10.8 per cent of the population. The figure, from the World Bank actually represented the total number of Greeks living abroad, not the number who emigrated in 2010.
Why might they have been spotted? The numbers are just too big. I didn't know how many supermarkets there are in the UK, but it took me less than two minutes to find out. There are around 8,000, according to the website of IGD (formerly the Institute of Certificated Grocers). So the claim that there are already another 16,000 in the pipeline is simply implausible.
The Greek claim is also far too high to be credible. People just don't emigrate as fast as this, unless they are fleeing a war. It would be the equivalent of more than 6 million people leaving Britain in a single year, unimaginable.
The reader suggests Guardian reporters believe it is of no consequence to misunderstand or misreport numbers in a story. Certainly this website contains several examples from The Guardian, usually a tendency to treat millions and billions as if they are interchangeable.
Chris Elliott says he has organised three sessions with external statistical experts for Guardian journalists in the past year. (I can vouch for one of these, as I provided it.) But the problem persists. He agrees with the reader there is a need for a profound cultural change.
All credit to the paper for washing its dirty linen so publicly. But not so much credit for numeracy.