Papers by Marietjie Potgieter
African Journal of Research in Mathematics, Science and Technology Education, Sep 13, 2013
African Journal of Research in Mathematics, Science and Technology Education, Sep 13, 2013
International Journal of Science Education, 2010
This study investigated the use of performance–confidence relationships to signal the presence of... more This study investigated the use of performance–confidence relationships to signal the presence of alternative conceptions and inadequate problem‐solving skills in mechanics. A group of 33 students entering physics at a South African university participated in the project. The test instrument consisted of 20 items derived from existing standardised tests from literature, each of which was followed by a self‐reported measure of confidence of students in the correctness of their answers. Data collected for this study included students’ responses to multiple‐choice questions and open‐ended explanations for their chosen answers. Fixed response physics and confidence data were logarithmically transformed according to the Rasch model to linear measures of performance and confidence. The free response explanations were carefully analysed for accuracy of conceptual understanding. Comparison of these results with raw score data and transformed measures of performance and confidence allowed a re‐evaluation of the model developed by Hasan, Bagayoko, and Kelley in 1999 for the detection of alternative conceptions in mechanics. Application of this model to raw score data leads to inaccurate conclusions. However, application of the Hasan hypothesis to transformed measures of performance and confidence resulted in the accurate identification of items plagued by alternative conceptions. This approach also holds promise for the differentiation between over‐confidence due to alternative conceptions or due to inadequate problem‐solving skills. It could become a valuable tool for instructional design in mechanics.
Chemistry Education Research and Practice, 2010
Journal of Research in Science Teaching, 2008
Students in undergraduate chemistry courses find, as a rule, topics with a strong mathematical ba... more Students in undergraduate chemistry courses find, as a rule, topics with a strong mathematical basis difficult to master. In this study we investigate whether such mathematically related problems are due to deficiencies in their mathematics foundation or due to the complexity introduced by transfer of mathematics to a new scientific domain. In the investigation we exposed a group of students to a chemistry instrument based on the Nernst equation in electrochemistry, and an equivalent group of students to a similar mathematics instrument in which the questions were stripped of all chemistry context. Both tests contained items requiring algebraic as well as graphical skills. Students experienced few problems with the algebraic questions in both the chemistry and mathematics tests. Their graphical construction and interpretation skills, on the other hand, are inadequate, as can be seen from the poor performance in both the mathematics and the chemistry results of the graphical question. Our conclusion is that the problem seems to lie at the mathematics side and is not due to the transfer of mathematics to an application. © Wiley Periodicals, Inc. J Res Sci Teach 45: 197–218, 2008.
International Journal of Mathematical Education in Science and Technology, 2005
The general perception is that high school teaching of mathematics tends to be fairly procedural ... more The general perception is that high school teaching of mathematics tends to be fairly procedural in South Africa and that students that enter university are better equipped to deal with procedural problems rather than conceptual. In this study we compare the conceptual and procedural skills of first year calculus students in life sciences. We also investigate students' confidence in handling conceptual and procedural problems.
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Papers by Marietjie Potgieter