This article presents a step-by-step guide to using R and SPSS to bootstrap exam questions. Bootstrapping, a versatile nonparametric analytical technique, can help to improve the psychometric qualities of exam questions in the process of quality assurance. Bootstrapping is particularly useful in disciplines such as medical education, where student…

This study investigated the effect of complex structure on dimensionality assessment in compensatory multidimensional item response models using DETECT- and NOHARM-based methods. The performance was evaluated via the accuracy of identifying the correct number of dimensions and the ability to accurately recover item groupings using a simple…

Item response theory (IRT) has so many advantages than its precedent Classical Test Theory (CTT) such as non-changing item parameters, ability parameter estimations free from the items. However, in order to get these advantages, some assumptions should be met and they are; unidimensionality, normality and local independence. However, it is not…

The aim of this study is to investigate the influence of content knowledge on students' socio-scientific argumentation in the Swedish National Assessment in biology, chemistry and physics for 12-year-olds. In Sweden, the assessment of socio-scientific argumentation has been a major part of the National Assessment during three consecutive years and…