Studies have been done (Kohn cites one in "The Folly Of Merit Pay") that show more teachers are driven out of teaching by the unintended negative consequences o

Studies have been done (Kohn cites one in "The Folly Of Merit Pay") that show more teachers are driven out of teaching by the unintended negative consequences of performance-based pay than are attracted to it by the prospect of more money. That certainly makes sense, but the question addressed in this article was not quantity but quality. Which one attracts a higher caliber of teacher (for whichever definition of higher caliber is being used at the moment)?