A variety of resources are available from which researchers can identify measurement instruments, including peer-reviewed journal articles, collections of technical information about published instruments, and electronic databases that are sponsored by universities, testing organizations, and other groups. Although these resources are widespread,…

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…

About 45 R packages to analyze data using item response theory (IRT) have been developed over the last decade. This article introduces these 45 R packages with their descriptions and features. It also describes possible advanced IRT models using R packages, as well as dichotomous and polytomous IRT models, and R packages that contain applications…

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…

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…

Lee Cronbach once expressed the view that all roads lead to construct validity. In looking to clarify the consensus definition of validity, and its place in assessment, Newton is also led to the troublesome idea of construct validity. To be sure, he addresses other validity issues, but in this commentary, I will restrict my attention to construct…

This article is a commentary of a paper by Derek C. Briggs and Frederick A. Peck, "Using Learning Progressions to Design Vertical Scales That Support Coherent Inferences about Student Growth," which describes an elegant potential framework for at least beginning to address three priorities in large-scale assessment that have not been…

Standard setting is a systematic process that uses a combination of judgmental and empirical procedures to make recommendations about where on the score continuum "cut scores" should be placed. Cut scores divide the score scale into categories consistent with the descriptions of student performance associated with multiple levels of achievement.…

The last century was marked by dazzling changes in many areas, such as technology and communications. Predictions into the second century of testing are seemingly difficult in such a context. Yet, looking back to the turn of the last century, Kirkpatrick (1900), in his American Psychological Association presidential address, presented fundamental…