Coefficient alpha reliability persists as the most common reliability coefficient reported in research. The assumptions for its use are, however, not well-understood. The current paper challenges the commonly used expressions of coefficient alpha and argues that while these expressions are correct when estimating reliability for summed scores,…

One of the primary goals of international large-scale assessments in education is the comparison of country means in student achievement. This article introduces a framework for discussing differential item functioning (DIF) for such mean comparisons. We compare three different linking methods: concurrent scaling based on full invariance,…

Increasing use of item pools in large-scale educational assessments calls for an appropriate scaling procedure to achieve a common metric among field-tested items. The present study examines scaling procedures for developing a new item pool under a spiraled block linking design. The three scaling procedures are considered: (a) concurrent…

The growing use of scales in survey questionnaires warrants the need to address how does polytomous differential item functioning (DIF) affect observed scale score comparisons. The aim of this study is to investigate the impact of DIF on the type I error and effect size of the independent samples t-test on the observed total scale scores. A…

This study defines subpopulation item parameter drift (SIPD) as a change in item parameters over time that is dependent on subpopulations of examinees, and hypothesizes that the presence of SIPD in anchor items is associated with bias and/or lack of invariance in three psychometric outcomes. Results show that SIPD in anchor items is associated…

Recent research has shown how the statistical bias in Rasch model difficulty estimates induced by guessing in multiple-choice items can be eliminated. Using vertical scaling of a high-profile national reading test, it is shown that the dominant effect of removing such bias is a nonlinear change in the unit of scale across the continuum. The…

International large-scale assessments are on the rise, with the Programme for International Student Assessment (PISA) seen by many as having strategic prominence in education policy debates. The present article reviews PISA-related English-language peer-reviewed articles from the programme's first cycle in 2000 to its most current in 2015. Five…

This booklet grew out of a half-day class on equating that author Samuel Livingston teaches for new statistical staff at Educational Testing Service (ETS). The class is a nonmathematical introduction to the topic, emphasizing conceptual understanding and practical applications. The class consists of illustrated lectures, interspersed with…

Stewart questioned Beglar's use of Rasch analysis of the Vocabulary Size Test (VST) and advocated the use of 3-parameter logistic item response theory (3PLIRT) on the basis that it models a non-zero lower asymptote for items, often called a "guessing" parameter. In support of this theory, Stewart presented fit statistics derived from…

Though addressing sources of uncertainty is an important part of doing science, it has largely been neglected in assessing students' scientific argumentation. In this study, we initially defined a scientific argumentation construct in four structural elements consisting of claim, justification, uncertainty qualifier, and uncertainty…

This paper uses an approximate average percent-correct methodology to compare the ranks that would be obtained for PISA 2006 countries if the rankings had been derived from items judged by each country to be of highest priority for inclusion. The results reported show a remarkable consistency in the country rank orderings across different sets of…

The population sensitivity of vertical scaling results was evaluated for a state reading assessment spanning grades 3-10 and a state mathematics test spanning grades 3-8. Subpopulations considered included males and females. The 3-parameter logistic model was used to calibrate math and reading items and a common item design was used to construct…

This research aims to reveal the validation of 86-items in order to develop a scale for evaluating constructivist approach integrated online courses in higher education practices. The main aim of this research process is to reveal a scale to further evaluate whether the online education practices in higher education have the notions of…

This report is structured so as to provide technical detail about each aspect of International Civic and Citizenship Education Study (ICCS). The overview is followed by a series of chapters that provide detail about different aspects of ICCS. Chapters, 2, 3, 4, and 5 are concerned with the instruments. Chapter 2 provides information about the…

This manual contains information about the American College Test (ACT) Plan® program. The principal focus of this manual is to document the Plan program's technical adequacy in light of its intended purposes. This manual supersedes the 2011 edition. The content of this manual responds to requirements of the testing industry as established in the…