Value added models (VAMs) attempt to estimate the causal effects of teachers and schools on student test scores. We apply Generalizability Theory to show how estimated VA effects depend upon the selection of test items. Standard VAMs estimate causal effects on the items that are included on the test. Generalizability demands consideration of how…

Ongoing or recently completed across the United States are a series of lawsuits via which teacher plaintiffs are contesting how they are being evaluated using value-added models (VAMs) as part of states'/districts' teacher accountability systems. To investigate the empirical and pragmatic matters addressed in court, researchers conducted a case…

In this study, researchers compared the concordance of teacher-level effectiveness ratings derived via six common generalized value-added model (VAM) approaches including a (1) student growth percentile (SGP) model, (2) value-added linear regression model (VALRM), (3) value-added hierarchical linear model (VAHLM), (4) simple difference (gain)…

There is an enduring issue on whether student- and school-level covariates should be included in value-added school effects models, in addition to prior achievement. Proponents argue that the addition of covariates allows fairer comparisons of schools, whereas opponents argue that it excuses poorly performing schools and obscures policy-relevant…

Education systems focus on issues related to school effects and differences. School effects are used as a basis for accountability in various countries including China. This study investigated the stability and cross-disciplinary consistency of value-added estimates based on student scores in selected schools in a city in central China. The…

This study introduces the signal weighted teacher value-added model (SW VAM), a value-added model that weights student-level observations based on each student's capacity to signal their assigned teacher's quality. Specifically, the model leverages the repeated appearance of a given student to estimate student reliability and sensitivity…

Contemporary teacher evaluation systems use multiple measures of performance to construct ratings of teacher quality. While the properties of constituent measures have been studied, little is known about whether composite ratings themselves are sufficiently reliable to support high-stakes decision making. We address this gap by estimating the…

While states are no longer required to set up teacher evaluation systems based in significant part on student test scores, quite a few continue to use value-added (VAMs) or student growth percentile (SGP) models for that purpose. In this study, we analyzed three years of teacher data to illustrate the performance of teachers' median growth…

Researchers and policymakers in the US and beyond increasingly seek to identify teaching qualities that are associated with academic achievement gains for K-12 students through effectiveness studies. Yet teaching quality varies with academic content and social contexts, involves multiple participants, and requires a range of skills, knowledge, and…

Because the pandemic exacerbated chronic absenteeism in many parts of the country, the need to understand how schools can improve student attendance has never been greater. Accordingly, this study breaks new ground by examining high schools' contributions to attendance after accounting for individual students' prior absenteeism and other…

The traditional approach to estimating the consistency of school effects across subject areas and the stability of school effects across time is to fit separate value-added multilevel models to each subject or cohort and to correlate the resulting empirical Bayes predictions. We show that this gives biased correlations and these biases cannot be…

States and districts need ways of measuring principal performance that correctly identify effective principals. Unfortunately, existing research offers little guidance to policymakers on which types of performance measures provide valid information about principals' contributions to student achievement. States have therefore had to develop…

Background: Value-added modeling (VAM) has been used to rank teachers and assess teacher and school quality. The apparent relationship between value-added teacher rankings and gains in student performance provide a foundation for the view that the contribution of teachers to student performance is the largest factor influencing student…

The purpose of this research was to determine if the Pennsylvania Value-Added Assessment System Average Growth Index (PVAAS AGI) scores, derived from standardized tests and calculated for Pennsylvania schools, provide a valid and reliable assessment of teacher effectiveness, as these scores are currently used to derive 15% of the annual…

Papay (2011) noticed that teacher value-added measures (VAMs) from a statistical model using the most common pre/post testing timeframe--current-year spring relative to previous spring (SS)--are essentially unrelated to those same teachers' VAMs when instead using next-fall relative to current-fall (FF). This is concerning since this choice--made…