It is demonstrated that the popular three-parameter logistic model can lead to markedly inaccurate individual ability level estimates for mixture populations. A theoretically and empirically important setting is initially considered where (a) in one of two subpopulations (latent classes) the two-parameter logistic model holds for each item in a…

Latent class Poisson count models are used to analyse a sample of Danish test score results from a cohort of individuals born in 1954-1955, tested in 1968, and followed until 2011. The procedure takes account of unobservable effects as well as excessive zeros in the data. We show that the test scores measure manifest or measured ability as it has…

Value-added models have caught the interest of policymakers because, unlike using student tests scores for other means of accountability, they purport to "level the playing field." That is, they supposedly reflect only a teacher's effectiveness, not whether she teaches high- or low-income students, for instance, or students in accelerated or…

There are good reasons for re-thinking teacher evaluation. Evaluation systems in most school districts appear to be far from rigorous. A recent study showed that more than 99 percent of teachers in a number of districts were rated "satisfactory," which does not comport with empirical evidence that teachers differ substantially from each…

Measuring a teacher's effectiveness in quantifiable ways is a logical step in a society driven by the SMART goals (specific, measurable, attainable, relevant, and timely objectives) that pervade modern management. The idea of using student performance on standardized tests to judge a teacher's effectiveness picked up steam after the Obama…

Diagnostic scores are of increasing interest in educational testing due to their potential remedial and instructional benefit. Naturally, the number of educational tests that report diagnostic scores is on the rise, as are the number of research publications on such scores. This article provides a critical evaluation of diagnostic score reporting…

This problem-based learning project addressed the need to improve the construction and implementation of value-added teacher evaluation policies and instruments. State officials are constructing value-added teacher evaluation models due to accountability initiatives, while ignoring the holes and problems in its implementation. The team's…

This problem-based learning project addressed the need to improve the construction and implementation of value-added teacher evaluation policies and instruments. State officials are constructing value-added teacher evaluation models due to accountability initiatives, while ignoring the holes and problems in its implementation. The team's…

This problem-based learning project addressed the need to improve the construction and implementation of value-added teacher evaluation policies and instruments. State officials are constructing value-added teacher evaluation models due to accountability initiatives, while ignoring the holes and problems in its implementation. The team's…

The use of value-added modeling (VAM) in school accountability is expanding, but deciding how to embrace VAM is difficult. Various experts say it's too unreliable, causes more harm than good, and has a big margin for error. Others assert VAM is imperfect but useful, and provides valuable feedback. A closer look at the models, and their use,…

Ensuring teacher effectiveness in the classroom has been a cornerstone of the current administration's education platform. This brief policy analysis focuses on the evaluation systems used in states for special educators, including related services providers. The document was completed as part of the Cooperative Agreement between Project Forum at…

Changes to state tests impact the ability of State Education Agencies (SEAs) to monitor change in performance over time. The purpose of this study was to evaluate the Standardized Performance Growth Index (PGIz), a proposed statistical model for measuring change in student and school performance, across transitions in tests. The PGIz is a…

This study examined the correlation between the grades a student earns in his or her classroom and the scores that each student earned on the Colorado Student Assessment Program tests in Writing, Math, and Science. The study also examined the mean scores of varying sub-groups to determine if certain sub-groups demonstrated higher means, dependent…

Although many researchers and policy analysts (e.g., Harris, Glazerman et al., 2011; 2010) consider value-added to be the state of the art in school and teacher productivity measurement, only a minority of Teacher Incentive Fund (TIF) Round 1 and 2 grantees used value-added as a measure of school or teacher performance. Fourteen of the 34 grantees…

This paper provides a history of ETS's role in developing assessment instruments and psychometric procedures for measuring change in large-scale national assessments funded by the Longitudinal Studies branch of the National Center for Education Statistics. It documents the innovations developed during more than 30 years of working with…