Skip to main content

Diane Ravitch’s Blog: Columbia Economist Says Chetty, Friedman, and Rockoff Are Wrong About VAM

Moshe Adler, professor of economics at Columbia University, has emerged as one of the most incisive critics of the work of Raj Chetty, John Friedman, and Jonah Rockoff on Value-added measurement (VAM).

In the recent Vergara decision about tenure for teachers in California, the study by Raj Chetty and John Friedman of Harvard and Jonah Rockoff of Columbia played a prominent role. But according to the economist Moshe Adler the study is wrong and misleading. According to Adler, the authors suppressed a result that contradicts their main claim, they picked and chose which data sets to use, they used a misleading method of analysis that inflated their results and they misrepresented research that contradicts their claims as supporting them. These are just a few of the problems with the scientific integrity with the study. Adler wrote his review for the National Education Policy Center and it can found at: http://nepc.colorado.edu/newsletter/2014/06/adler-response-to-chetty)

A short time after the publication of his NEPC review, Adler received an email from Chetty that informed him that the study had been accepted for publication by the American Economic Review (AER). (Chetty also suggested that a Nobel Prize will likely follow!) Adler immediately wrote to the editors of the AER to alert them to the grave scientific problems with the study. The editor-in-charge did not evaluate Adler’s objections herself, nor did she send them to the referees to evaluate. Instead, she forwarded Adler’s letter to the authors who then replied to Adler’s NEPC review. The editor found this reply satisfactory, but as Adler explains in his response, Chetty’s et al.’s reply is without merit, and it only adds to the problems with the research. Chetty’s letter to Adler and Adler’s correspondence with the AER can be found at: http://www.columbia.edu/~ma820/Chetty%20Adler%20AER.htm

This blog post, which first appeared on the

website, has been shared by permission from the author.
Readers wishing to comment on the content are encouraged to do so via the link to the original post.
Find the original post here:

The views expressed by the blogger are not necessarily those of NEPC.

Diane Ravitch

Diane Ravitch is Research Professor of Education at New York University and a historian of education. She is the Co-Founder and President of the Network for Publi...