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…

The semantics, or meaning, of validity is a fluid concept in educational and psychological testing. Contemporary controversies surrounding this concept appear to stem from the proper location of validity. Under one view, validity is a property of score-based inferences and entailed uses of test scores. This view is challenged by the…

E. L. Thorndike contributed significantly to the field of educational and psychological testing as well as more broadly to psychological studies in education. This article follows in his testing legacy. I address the escalating demand, across societal sectors, to measure individual and group competencies. In formulating an approach to measuring…

What is validity? A simple question but apparently one with many answers, as Paul Newton highlights in his review of the history of validity. The current definition of validity, as entertained in the 1999 "Standards for Educational and Psychological Testing" is indeed a consensus, one between the classical notion of attributes, and measures…

With the debut of common assessments less than two years away, states and districts are worried about the accountability systems that hinge on those tests. A growing chorus of policy groups is urging more flexibility in how states evaluate teachers, label schools, and enforce other high-stakes consequences during what's likely to be a messy…

Recently, student outcomes have bubbled to the top of debates about how to evaluate teaching in community and liberal arts colleges, universities, and professional schools, but even more international attention has been riveted on how outcomes are being used to evaluate teachers and administrators K-12 (Harris, 2012; Rowen & Raudenbush, 2016;…

In 2009, the Bill and Melinda Gates Foundation funded the investigation of a $45 million question: How can we identify and develop effective teaching? Now that the findings from their Measures of Effective Teaching (MET) project have been released, it's clear they asked a simpler question, namely, What other measures match up well with value-added…

The 1999 "Standards for Educational and Psychological Testing" defines validity as the degree to which evidence and theory support the interpretations of test scores entailed by proposed uses of tests. Although quite explicit, there are ways in which this definition lacks precision, consistency, and clarity. The history of validity has taught us…

The levels and growth achievement functions make extreme and diametrically opposed assumptions about the rate at which teacher inputs persist. I first show that if these assumptions are incorrect, teacher value-added estimates can be significantly biased. I then develop a tractable, cumulative model of student achievement that allows for the joint…

The use of "value added" information appears poised to expand into the nation's teacher colleges, with more than a dozen states planning to use the technique to analyze how graduates of training programs fare in classrooms. Supporters say the data could help determine which teacher education pathways produce teachers who are at least as…

It sounds so simple. If tests measure what a student learned, why can't they also be used to measure what a teacher taught? Wouldn't this data make it easy to distinguish good teachers from bad? And can't this information be used in teacher retention, tenure, salary, and other decisions? The use of student performance data to judge the quality of…

The use of value-added modeling (VAM) in school accountability is expanding. However, trying to decide how to embrace VAM can be rather nettlesome. Some experts claim it is "too unreliable," causes "more harm than good," and has "a big margin for error," while other experts assert VAM is "imperfect, but…

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,…

Everyone knows what "good" teaching is. Or do they? Although the definition of a good teacher has evolved over time, teachers have consistently been seen as responsible for effecting change. According to the current value-added model, effective teaching is not framed in terms of the specific actions of the teacher, but in terms of students'…

Last May, the seven most recent New York State Teacher of the Year award winners joined the 1993 recipient in sounding the alarm bell over the state's new plan to stake 40 percent of teachers' performance evaluations on students' standardized test scores. In their letter to Chancellor Merryl Tisch and the state Board of Regents, the teachers said…