Abstract Students' understanding degree of disciplinary core concepts directly impacts the achievement of the learning targets. The national science education standards in China and other countries pay great attention on cultivating students' ability of conceptual understanding to improve the civic scientific literacy. For exploring and identifying students' conceptual understanding, content-specific concept in a certain level of learning progression needs to be concerned. Compared with other types of diagnostic tools, two-tier diagnostic instrument is more precisely and concretely. Furthermore, Rasch modeling theory is better than classical testing theory in validating the quality of measurement instrument. Thus, this paper took an example of the concepts of "ionic equilibrium in solution" to illustrate how to develop two-tier diagnostic instrument for measuring students' conceptual understanding, and to present how to use Rasch modeling to validate and revise the measurement instrument.
HE Peng, ZHENG Chang-Long. Instrument Development and Validation for Measuring Students' Understanding of Chemical Core Concepts Based on Rasch Modeling Study[J]. Chinese Journal of Chemical Education, 2018, 39(17): 1-7.