This dissertation includes two independent research projects, one in astronomy education research and the other in planetary science/astrophysics research. In the first research effort, we investigate college students' conceptual and reasoning difficulties on the topic of planet formation pre-instruction. Through an analysis of over 1,000…

Chemical representations play an important role in helping learners to understand chemical contents. Thus, dealing with chemical representations is a necessity for learning chemistry, but at the same time, it presents a great challenge to learners. Due to this great challenge, it is not surprising that numerous national and international studies…

Test scores are used to assess one's general knowledge of a specific area. Although strategies to improve test performance have been previously identified, the consistency with which one uses these strategies has not been analyzed in such a way that allows assessment of how much consistency affects overall performance. Participants completed one…

This study examined the Flynn Effect (FE; i.e., the rise in IQ scores over time) in Estonia from Scale B of the National Intelligence Test using both classical test theory (CTT) and item response theory (IRT) methods. Secondary data from two cohorts (1934, n = 890 and 2006, n = 913) of students were analyzed, using both classical test theory (CTT)…

The purpose of multiple choice tests of medical knowledge is to estimate as accurately as possible a candidate's level of knowledge. However, concern is sometimes expressed that multiple choice tests may also discriminate in undesirable and irrelevant ways, such as between minority ethnic groups or by sex of candidates. There is little literature…