Performance evaluation of teachers
…observable teacher characteristics like graduate education and experience are not typically correlated with increased productivity [among teachers]. Many researchers and policymakers have suggested that, under these conditions, the only way to adjust the teacher distribution for the better is to gather information on individual productivity through evaluation and then dismiss low performers. This paper offers evidence that evaluation can shift the teacher effectiveness distribution through a different mechanism: by improving teacher skill, effort, or both in ways that persist long-run.
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We find that teachers are more productive during the school year when they are being evaluated, but even more productive in the years after evaluation. A student taught by a teacher after that teacher has been through the Cincinnati evaluation will score about 10 percent of a standard deviation higher in math than a similar student taught by the same teacher before the teacher was evaluated.
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our estimates indicate that postevaluation improvements in performance were largest for teachers whose performance was weakest prior to evaluation, suggesting that teacher evaluation may be an effective professional development tool.
Not a surprising result but it’s always nice to have the empirics to back up your assertions.