As the largest international study ever taken in history, the Trend in Mathematics and Science Study (TIMSS) has been held as a benchmark to measure U.S. student performance in the global context. In-depth analyses of the TIMSS project are conducted in this study to examine key issues of the comparative investigation: (1) item flaws in mathematics…

When comparing data derived from tests or questionnaires in cross-national studies, researchers commonly assume measurement invariance in their underlying scaling models. However, different cultural contexts, languages, and curricula can have powerful effects on how students respond in different countries. This article illustrates how the…

Several current international comparative large-scale assessments of educational achievement (ICLSA) make use of "Rasch models", to address functions essential for valid cross-cultural comparisons. From a historical perspective, ICLSA and Georg Rasch's "models for measurement" emerged at about the same time, half a century ago. However, the…

Use of item response theory (IRT), the delta plot method, and Mantel-Haenszel techniques to assess differential item functioning (DIF) across racial and gender groups associated with the Maryland Test of Citizenship Skills (MTCS) is described. The objective of this research was to determine the: effect of sample size on results from these three…