Today, the National Center on Performance Incentives (NCPI) and the RAND Corporation released a long-awaited experimental evaluation of teacher performance pay in Nashville, Tenn. It finds that performance bonuses have virtually no effect on student math test scores (there were small but significant gains by fifth graders, but only in two of the three years examined, and the gains did not last into sixth grade).
Since this is such a politically contentious issue, these findings are likely to spark a lot of posturing and debate. So it’s worth trying to put them in context. As I discussed in a prior post, we now have at least preliminary results from three randomized experimental evaluations of merit pay in the U.S., the first contemporary, high-quality evidence of its kind. This Nashville report and the two previously-released studies – one from Chicago and one from New York City's schoolwide bonus program – reached the same conclusion: Performance bonuses for teachers have little or no discernable effect on student test scores.
Although the NYC and Chicago findings are preliminary (the evaluations are still in progress), the NYC program provides schoolwide and not individual bonuses, and one additional study (Round Rock, Tex.) is yet to be released, the three already-released reports do represent a fairly impressive, though still very tentative, body of evidence on merit pay’s utility as a means to improve test scores.
And at this point, it’s a good bet that, when all the evaluations are final and the smoke has cleared, we will have to conclude that performance bonuses are, at the very least, a very unpromising policy for producing short-term test score gains.