Eugene Stern: How Value Added Models are Like Turds

Eugene Stern critiques the Value Added Model for teacher assessment thusly:
So, just to take another example, if I decided to rate teachers by the size of the turds that come out of their ass, I could wave around a lovely bell-shaped distribution of teacher ratings, sit back, and wait for the Times article about how statistically insightful this is.
Read more at MathBabe.