Disengaged test taking tends to be most prevalent with low-stakes tests. This has led to questions about the validity of aggregated scores from large-scale international assessments such as PISA and TIMSS, as previous research has found a meaningful correlation between the mean engagement and mean performance of countries. The current study, using…

Using an empirically-based simulation study, we show that typically used methods of choosing an item calibration sample have significant impacts on achievement bias and system rankings. We examine whether recent PISA accommodations, especially for lower performing participants, can mitigate some of this bias. Our findings indicate that standard…

Differential item functioning (DIF) analysis is a statistical technique used for ensuring the equity and fairness of educational assessments. This study formulates a new DIF analysis method using the information similarity index (ISI). ISI compares item information functions when data fits the Rasch model. Through simulations and an international…