Lies, Damned Lies, and Educational Statistics

One week till the well-deserved summer break, and I hope all fellow teachers get the opportunity to recharge. Summer does, of course, contain the two results days, which secondary teachers now look forward to with as much anxiety and trepidation as the students. Not least because their pay and career prospects now depend at least in part on the performance on one particular day of a group of largely unpredictable teenagers!

However, I’d go further : their pay and career also depends not just on the actual results of those teenagers, but on the ability of school “leaders” to understand and use data. I don’t know which is more terrifying.

This blog has two parts. The first part recounts a couple of stories of how, in our targets-and-results-obsessive education culture,¬†statistics based on small sample sizes (like your class)¬†can be desperately misleading, and offers a way in which you can defend yourself against overly simplistic statistical judgments about whether you’ve been a “good” or “bad” teacher. The second part goes a bit further and poses the question of whether “good” and “bad” teachers actually exist in anything like the way they are portrayed by media and Ministers, and invites readers to do their own simple statistical search for the “Good” teacher(s) in their school.

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