Value-added models for teacher evaluation and accountability: commonsense assumptions

Despite the concerns regarding value-added models (VAMs), advocates hold strong to VAMs’ theoretical strengths and potentials, while adopting a set of agreed-upon albeit “heroic” set of assumptions, without research in support. These assumptions transcend promotional, policy, media, and research-based pieces, but they have never been made explicit as analyzed as a set or whole. The purpose of this study was to make unambiguous the assumptions that have been made within the VAM narrative that have often been accepted without challenge, and situate these assumptions within the research. Sources for analyses included 470 pieces, published within traditional and nontraditional outlets, from which we derived 27 prevailing assumptions.