Like all quasi-experiments, this one relies on an assumption that the treatment – here, teacher switching – is as good as random. I find that it is not: Teacher switching is correlated with changes in students’ prior-year scores
Pointer from Tyler Cowen.
Thus, Rothstein hopes to debunk a famous paper by Raj Chetty and others which claimed to shows that great teachers add a lot of value. My guess is that Rothstein will fail. It reminds me of when Bill Wascher and others debunked the Krueger-Card paper claiming to show that higher minimum wage laws do not reduce employment. Once a result is put into the literature by a high-status economist and the result supports progressive policy preferences, it becomes undebunkable.
And you’re right, I’m not being charitable to those who disagree.