New analysis challenges Gates study on value-added measures
Last month, a Gates Foundation study was released and said to be evidence of the validity of “value-added” measures to evaluate the effectiveness of teachers by using students’ standardized test scores. But a new analysis of that report concludes that the substance of the report doesn’t support its conclusions. The report released last month was called “Learning About Teaching: Initial Findings from the Measures of Effective Teaching Project,” by Bill & Melinda Gates Foundation officials Thomas J. Kane and Steven Cantrell. They used data from six major urban school districts to examine correlations between student survey responses and value-added scores computed both from state tests and from higher-order tests of conceptual understanding. Kane and Cantrell concluded that the evidence suggests that value-added measures can be constructed to be valid; others described the report as strong evidence of support for this approach. But Economics Professor Jesse Rothstein at the University of