In this article we discuss the findings of our research on students' understanding of vector concepts in problems without physical context. First, we develop a complete taxonomy of the most frequent errors made by university students when learning vector concepts. This study is based on the results of several test administrations of open-ended…

Domain scores have been proposed as a user-friendly way of providing instructional feedback about examinees' skills. Domain performance typically cannot be measured directly; instead, scores must be estimated using available information. Simulation studies suggest that IRT-based methods yield accurate group domain score estimates. Because…

Web-based courses are promising in that they are effective and have the possibility of their instructional design being improved over time. However, the assessments of said courses are criticized in terms of their validity. This paper is an exploratory case study regarding the validity of the assessment system used in a semi presential web-based…