Research shows that assuming a test scale is equal-interval can be problematic, especially when the assessment is being used to achieve a policy aim like evaluating growth over time. However, little research considers whether teacher value added is sensitive to the underlying test scale, and in particular whether treating an ordinal scale as…

In this study, we compare the teacher quality distributions in charter schools and traditional public schools, and examine mechanisms that might explain cross-sector differences in teacher effectiveness as measured by teacher value-added scores using school and teacher level data from Florida. We have three main findings. First, we find that…

Evidence that teachers' short-term instructional effects persist over time and predict substantial long-run impacts on students' lives provides much of the impetus for a wide range of educational reforms focused on identifying and responding to differences in teachers' value-added to student learning. However, relatively little research has…