"I'm in favour of performance-related pay [for teachers]," Labour's new education spokesman Tristram Hunt said on Question Time on Thursday evening.
Really? But why? Hunt is a historian by training, with a PhD from Cambridge. You would assume that he understands the importance of collecting and analysing empirical evidence before coming to a considered conclusion.
Yet the bulk of the empirical evidence on both sides of the Atlantic suggests performance-related pay (PRP) is a dud; it doesn't work on its own terms, i.e. raising the performance of students.
Consider just four brief examples.
1) In September 2010, the National Center on Performance Incentives at Vanderbilt University's Peabody College of education and human development announced the results of "a three-year experiment - the first scientific study of performance pay ever conducted in the United States".
Nearly 300 teachers volunteered to participate and roughly half of them were randomly assigned to a "treatment" group, in which they were eligible for bonuses of up to $15,000 per year on the basis of their students' exam performances.
The other half were assigned to a "control" group in which they weren't eligible for these bonuses. Over the course of the three-year study, more than $1.2m in bonuses were paid out to the teachers in the "treatment" group.
Yet both groups produced students with similar exam results; the bonuses made no difference. As the Vanderbilt study concluded:
"[T]here was no overall effect on student achievement across the entire treatment group..."
2) In July 2011, the Rand Corporation conducted a study of a New York City programme that was designed to improve student performance through "school-based financial incentives" (i.e. PRP).
"Overall, the program had no positive effects on student achievement at any grade level."
"Researchers found no differences between the reported teaching practices, effort and attitudes of teachers in treatment schools and those of the control group."
But, perhaps best of all, the Rand study found:
"Other accountability incentives--such as receiving a high progress report grade or achieving adequate yearly progress targets--and intrinsic motivation were deemed by many teachers as more salient than financial rewards."
3) In May 2012, a study by the Organisation for Economic Co-Operation and Development (OECD) produced the following verdict:
"A look at the overall picture reveals no relationship between average student performance in a country and the use of performance-based pay schemes."
4) Then there is the Education Endowment Foundation, a respected and independent British charity which analysed the results of various "cross-national comparisons" and determined that
"the actual average impact [of PRP] has been close to zero. In India, there is evidence of the benefit of performance pay in the private sector but not the state sector, but it is not clear how this evidence applies in the UK."
(Note: none of the afore-mentioned studies were produced or commissioned by the "Trots" or "Marxists" who, according to Education Secretary Michael Gove, control the teachers' unions.)
So why is the shadow education secretary so keen on PRP? It doesn't work. "No relationship", "no overall effect", "close to zero" - for once, the researchers don't mince their words.
The truth is that the case for PRP is ideology masquerading as evidence. It is difficult to disagree with the assessment of education journalist and campaigner Fiona Millar:
"PRP has all the hallmarks of a classic Michael Gove reform: it is not based on evidence, will probably waste time, energy and goodwill when there are other effective ways to manage performance, and is likely to be divisive. Allied to the introduction of unqualified teachers, it is one more step down the road towards Gove's hidden agenda of cutting salaries and softening up the schools market for profit-making providers."
The question then is: why has the new education spokesman for the Labour Party signed up so proudly and publicly to Gove's 'hidden agenda'?
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