@EdWorkingPaper{ai25-1170, title = "Disparate Teacher Effects, Comparative Advantage, and Match Quality", author = "William Delgado", institution = "Annenberg Institute at Brown University", number = "1170", year = "2025", month = "April", URL = "http://www.edworkingpapers.com/ai25-1170", abstract = {Does student-teacher match quality exist? While prior research documents disparities in teachers' impacts across student types, it has not distinguished between sorting and causal effects as the drivers of these disparities. I develop a flexible disparate value-added model (DVA) and introduce a novel measure of teacher quality–revealed comparative advantage (CA)–that captures the degree to which teachers affect student outcome gaps. Leveraging a quasi-experimental teacher turnover design, I show that the CA measure accurately predicts teachers’ disparate impacts: a teacher with a 1 standard deviation in black CA increases black students' test scores by 1 standard deviation, with no effect on non-black students' test scores. This methodological contribution offers a framework to study match effects, with implications for policy efficiency and equity.}, }