Another "Reformer" Cherry-Picks Data
Not all reformers read a quantitative study that seems to confirm their opinions and then get rhapsodic in speculating about Mr. Keating, the teacher at the “tony prep school” portrayed in the classic film, Dead Poet’s Society. But, Sarah Rosenberg’s “Oh Captain! My Captain!” illustrates the common pattern of wonks who cherry-pick studies in order to support their preferred policies.
Rosenberg misstates the findings of the Calder Center’s “Portability of Teachers Effectiveness Across Schools,”by Zeyu Xu, Umut Ozek, and Matthew Corritore. It uses value-added data from tens of thousands of elementary and secondary school teachers in North Carolina and Florida, and it found, on the average, “either no change or a slight increase in a teacher’s measured effectiveness after changing schools.”
She then goes overboard in arguing, “This research should muffle critics of high-stakes evaluation systems who argue that teachers in low-performing schools cannot reach the same student achievement gains as other teachers and are punished when student achievement is incorporated into a teacher’s evaluation.”
Actually, Xu, et.al find the “pattern is most likely to be driven by regression to the mean and that it is not
Rosenberg misstates the findings of the Calder Center’s “Portability of Teachers Effectiveness Across Schools,”by Zeyu Xu, Umut Ozek, and Matthew Corritore. It uses value-added data from tens of thousands of elementary and secondary school teachers in North Carolina and Florida, and it found, on the average, “either no change or a slight increase in a teacher’s measured effectiveness after changing schools.”
She then goes overboard in arguing, “This research should muffle critics of high-stakes evaluation systems who argue that teachers in low-performing schools cannot reach the same student achievement gains as other teachers and are punished when student achievement is incorporated into a teacher’s evaluation.”
Actually, Xu, et.al find the “pattern is most likely to be driven by regression to the mean and that it is not
