Spin, spin and statistics

Here's an interesting story - or is it a non-story? - in the Guardian:

The three national exam boards have been accused of spinning last summer's A-level results in a "desperate" attempt to convince the public that it is not becoming easier to get a top grade, after the Guardian obtained figures that raise new questions about grade inflation.

It's a complicated argument about whether you judge grade inflation in A-levels by the number of grade A's. Last summer the exam boards argued that a difference between private and state schools meant that there was no grade inflation. That's hardly convincing. In the Guardian story:

Alan Smithers, professor of education at Buckingham University, said: "Private schools and schools in prosperous places start out with more pupils on the A-B borderline, and as marks rise more pupils in these schools tip into the A grade. In lower-scoring state schools, more pupils started out nearer the B-C and D-C border so the big rises are seen in B and C."

Looking at the figures and asking if they have been misused is on the face of it good journalism. But this seems to be redefining grade inflation, which has previously been about the number of students getting grade A's and indeed seems to be defined as such in the intro to the story quoted above. But, in any case, what's the big scandal if it's true? The media are so determined to prove dumbing down that it's not surprising that statistics get argued in different ways. The head of one board:

wondered "if there was any other country in the world where people would work so hard" to explain away evidence of improving standards.