The Persistence of School-Level Value-Added

Using longitudinal data for an entire state from 2004 to 2008, this article describes the results from an empirical investigation of the persistence of value-added school effects on student achievement in reading and math. It shows that when schools are the principal units of analysis rather than teachers, the persistence of estimated school effects across grades can only be reasonably identified by placing strong constraints on the variable persistence model implemented by Lockwood, McCaffrey, Mariano, and Setodji. In general, there are relatively strong correlations between the school effects estimated using these constrained models and a reference model that assumes full persistence. These correlations vary somewhat by grade and the underlying test subject. The results from this study indicate cautious support for previous findings that the assumption of full persistence for cumulative value-added effects may be untenable, and evidence is also presented, which indicates a strong interaction by test subject. However, the practical impact of violating the assumption of full persistence appears to be smaller in the context of schools than it is for teachers.