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A 'Summary Opinion' Of The Hoxby NYC Charter School Study


Was the study every peer-reviewed? If not, why not? And how can we extract from Hoxby's findings how much of the impact may have been due to peer effects?

Hi Leonie, I'm not certain, but I would strongly suspect that the paper is either undergoing peer review right now, or has already been through it. I'm curious myself how it turned out (or will turn out). As for peer effects, they are, as I note in the post (seventh to last paragraph), always difficult to isolate, even when treatment is randomly assigned. I would speculate that some (but not nearly all) of the positive charter testing gains are attributable to peer effects, but it's tough to say. Thanks for the comment, MD

Generally a good review of some of these issues here. One note, however. You be clear that you are reporting on gains in scores on particular math and reading tests. That might or might not be the same as performance as measured by other standardized tests or by individualized professional judgement by a knowledgeable expert. The goal should not be simply higher scores on tests. The goal should be true mastery of the curricular content. I have no reason to believe that Hoxby would ever made not of that potential difference. But I'll bet that Di Carlo will.

Hi MDC, Interestingly, this is not the first time that Hoxby's results have been questioned. In 2000, she released a paper asserting that increasing school choice improves educational outcomes for all students, to which Jesse Rothstein (currently Associate Professor of Public Policy and Economics at UC Berkeley) released a comment detailing her flawed methodology and falsification of data sets. Unable to replicate her results using her own code, he argued that her results were largely invalid. (View the paper here: Regardless of Hoxby prestigious record, it does make one doubtful of her findings. I think your rebuttal of this important and influential report is extremely valuable to this discourse. Anna YW


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