Susanna Loeb, Professor of Education Stanford University and Faculty Director for the Center for Education Policy Analysis, has a brief published by the Carnegie Foundation for the Advancement of Teaching
The question for this brief is whether education leaders can use value-added measures as tools for improving schooling and, if so, how to do this. Districts, states, and schools can, at least in theory, generate gains in educational outcomes for students using value-added measures in three ways: creating information on effective programs, making better decisions about human resources, and establishing incentives for higher performance from teachers. This brief reviews the evidence on each of these mechanisms and describes the drawbacks and benefits of using value-added measures in these and other contexts.
The brief concludes
- Value-added measures are not a good source of information for helping teachers improve because they provide little information on effective and actionable practices.
- School, district, and state leaders may be able to improve teaching by using value-added to shape decisions about programs, human resources, and incentives.
- Value-added measures of improvement are more precise measures for groups of teachers than they are for individual teachers, thus they may provide useful information on improvement associated with practices, programs or schools.
- Many incentive programs for staff performance that are based on student performance have not shown benefits. Research points to the difficulty of designing these programs well and maintaining them politically.
- Value-added measures for selecting and improving programs, for informing human resource decisions, and for incentives are likely to be more useful when they are combined with other measures.
- We still have only a limited understanding of how best to use value-added measures in combination with other measures as tools for improvement.
The use of value-added measures to evaluate individual teachers, especially when connected to high stakes personnel decisions is impossible to defend if one is guided by the research evidence, and the disastrous practical applications.
The full brief can be read below.