What the the statistical chances that a particular group of students with those backgrounds would turn out to yield a performance at the 89th percentile? I've no idea, but say it's 1% for the sake of argument. That would mean that 1% of similar classes with averagely competent teachers would achieve that score, all other things being equal. That's many thousands of classes at the national level.
It's like the argument made in a UK court not long ago that someone must be guilty because the chances of the evidence being a coincidence were millions to one. Of course in a population of millions such a coincidence becomes almost inevitable.
I've no idea if this teacher was good or bad, but that's something that should be determined by expert, informed evaluation not mindless statistical witch hunt.
All metrics have errors. If we fire 99 bad teachers and 1 good one, we've improved education. The goal here is to improve education, not provide a permanent job for education grads.
I've no idea if this teacher was good or bad, but that's something that should be determined by expert, informed evaluation...
Why do you believe this method has an error rate lower than VAM? I agree the error rate is harder to characterize, but that isn't the same thing.
What the the statistical chances that a particular group of students with those backgrounds would turn out to yield a performance at the 89th percentile? I've no idea, but say it's 1% for the sake of argument. That would mean that 1% of similar classes with averagely competent teachers would achieve that score, all other things being equal. That's many thousands of classes at the national level.
It's like the argument made in a UK court not long ago that someone must be guilty because the chances of the evidence being a coincidence were millions to one. Of course in a population of millions such a coincidence becomes almost inevitable.
I've no idea if this teacher was good or bad, but that's something that should be determined by expert, informed evaluation not mindless statistical witch hunt.