The Righties are wetting themselves because the national standards supposedly show higher results in larger classes.
Of course, you can’t compare data between schools with any validity – “they are not moderated, so one school’s “well below” may be another’s “at” or “above”” writes the newspaper that helpfully provided a tool to let you compare schools.
And Danyl at Dimpost has shown that a third of the supposed class size link is down to special schools. Not that it matters – because there’s no validity in comparing the data across schools.
The rest of the difference is probably down to deciles. Danyl has also shown that national standard results and decile are closely and unsurprisingly correlated. Not that it matters because making claims about national achievement based on unmoderated results from individual schools is nonsense.
So, what have we learned? Nothing. Certainly nothing about the impact of class sizes, anyway. But maybe a little more about the Rights’ willful blindness.
lprent: Added links. And while I’m on the post I’d have to say that Jonathon Milne at the Herald on Sunday needs to be sent back to school for both some basic remedial stats. Due to the lack of detail in his article to evaluate his useless maths, some remedial journalism looks in order as well.