Cognitive diagnostic models (CDMs) have great promise for providing diagnostic information to aid learning and instruction, and a large number of CDMs have been proposed. However, the assumptions and performances of different CDMs and their applications in regard to reading comprehension tests are not fully understood. In the present study, we…

One core area of research in Second Language Acquisition is the identification and definition of developmental stages in different L2s. For L2 French, Bartning and Schlyter (2004) presented a model of six morphosyntactic stages of development in the shape of grammatical profiles. The model formed the basis for the computer program Direkt Profil…

This article investigates how measurement models and statistical procedures can be applied to estimate the accuracy of proficiency classification in language testing. The paper starts with a concise introduction of four measurement models: the classical test theory (CTT) model, the dichotomous item response theory (IRT) model, the testlet response…

This study investigated the validity of four theoretically motivated traits of writing ability across English and Korean, based on elementary school students' responses to letter- and story-writing tasks. Their responses were scored analytically and analyzed using confirmatory factor analysis. The findings include the following. A model of writing…

Provides an introduction to structural equation modelling (SEM) for language research, including: general objectives of SEM applications relevant to language assessment; methodology and statistical assumptions about data that must be met; commonly-used SEM steps and concepts; application matters, with sample models; and recent critical discussions…