The construct validity and fairness of the international baccalaureate diploma programme mathematics internal assessment: a case study of the assessment at the United World College, China

This thesis outlines the findings of a mixed-methods study of the International Baccalaureate (IB) Diploma Programme (DP) Mathematics Internal Assessment (IA) carried out from students' and teachers' perspectives at an IB school in China. The present study examines the construct validity and fairness of the DP mathematics IA in the 2021–2022 academic year. The study took place in 2022, at the height of the COVID-19 pandemic in China, when IB examinations were cancelled in addition to school closures and other measures. The study of the validity and fairness of mathematics internal assessment in the context of a highly uncommon set of circumstances, as well as the lessons that may be learnt from these, is therefore given a new dimension. The study used a mixed-methods approach, including two phases. Phase One included semi-structured interviews with five teachers and 13 students at UWC China. A survey of students' perceptions of assessment criteria with an evaluation of the validity of mathematics IA was also conducted in Phase One. Phase Two comprised quantitative analyses of Diploma Programme Year 2 students' mathematics internal assessment results and their final grades, as well as the relationship between IBDP mathematics performance and academic records of other domains. The correlation coefficient was utilized to explain the degree to which the mathematics IA grades are associated with the mathematics final assessment grades awarded by the International Baccalaureate. The findings revealed a moderate correlation between IA scores and final mathematics grades. Furthermore, IB mathematics grades correlated significantly with physics (r = .556) but weakly with English (r = .27), which indicates that students' IA grades were valid and fair. The interview with teachers and students suggested that clearer assessment criteria and new explanatory skills of the construct should be revisited. These findings highlight some important implications for educators regarding the validity of IA grades, which may be used in the predicted grades or by international organizations for awarding the final marks. First, it is critical for both students and teachers to understand the subject and tiering of mathematics courses and comprehend the assessment objectives, which highlights a new requirement expected of learners rather than just at the subject level. Second, the construct of mathematics IA in requiring new skills has been revisited. In addition, it’s recommended that there are five main aspects in order to support effective teaching and learning in empirical practice. Last but not least, it should be borne in mind that the study took place in China in 2022, when IB examinations were cancelled due to COVID-19. This research suggests that when conducting mathematics internal assessments throughout the epidemic, research and transferable abilities are highlighted for gains beyond construct validity comprehension

Investigate the interaction between dark matter and dark energy

In this paper we investigate the interaction between dark matter and dark energy by considering two different interacting scenarios, i.e. the cases of constant interaction function and variable interaction function. By fitting the current observational data to constrain the interacting models, it is found that the interacting strength is non-vanishing, but weak for the case of constant interaction function, and the interaction is not obvious for the case of variable interaction function. In addition, for seeing the influence from interaction we also investigate the evolutions of interaction function, effective state parameter for dark energy and energy density of dark matter. At last some geometrical quantities in the interacting scenarios are discussed.Comment: 14 pages, 6 figure