Finding the Key Concepts of Students’ Knowledge: A Network Analysis of Coherence and Contingency of Knowledge Structures

The desired outcome of learning science is students’ expert-like subject knowledge, which is expected to be at the same time well-organized, coherent and contingent. However, it has proved difficult to find ways to represent these features and to identify the key conceptual elements or concepts that are responsible for them. In this study concept networks constructed by physics students’ representing their views of the relatedness of physics concepts are analyzed in order to clarify how coherence and contingency can be captured and measured. The data consist of concept networks (N=12) constructed by physics students, representing relationships between physics concepts of electricity and magnetism. The networks are first analyzed qualitatively for their epistemic acceptability. The structure of the concept networks is then analyzed quantitatively using a network graph theoretical approach. The analysis picks out a handful of key concepts which all play a central role in all of the concept networks examined. From the physics point of view these key concepts are relevant ones (most of them having to do with fields), which indicates the relevance and power of the method in describing knowledge structures.