Characterizing and Measuring Student Explanations of Chemical Equilibrium


Research on conceptual change, with the goal of characterizing the development of conceptual understanding, suffers from several extant theoretical and methodological challenges. There is little agreement over the central issues in the field, including what it means to “have a concept” or what the processes are by which conceptual change occurs. As a result, several competing theories co-exist in the literature, often explicitly contradictory.

I believe this difficulty is due, in part, to two issues. First, researchers lack explicit analytic means for unpacking the rich complexity and contextuality of cognitive activity, including deceptively simple activities such as answering a question during an interview or while taking a test. Consequently, researchers face a
persistent difficulty when attempting to disentangle the contributions of conceptual systems from the contributions of the social and interactional structures that likewise organize and constrain cognitive activity.

Second, although the various types of conceptual systems purported to be involved in conceptual change are distinguished by several qualitative properties, such as scope, researchers lack accurate, reliable, sample-independent, and theory-independent measures of these properties. Consequently, it is difficult to use such properties to compare the adequacy of different theories in explaining the same data, let alone data collected from different groups or with different methods.

The objective of my dissertation is to seek evidence for whether two fledgling theoretical and methodological innovations can begin to address the above challenges in a study of conceptual understanding. The project will focus on undergraduate student explanations of chemical phenomena involving dynamic equilibrium. In the first stage of the project, the nascent method of performance analysis will be used to characterize both the informational and interactional properties of student explanations given during a series of clinical interviews. Some of these qualitative properties will then be developed into hierarchical, interval scales, collectively called the Multidimensional Measure of Conceptual Complexity, for the purpose of accurately and precisely measuring these properties using Rasch measurement technology. The overarching goal is to see whether the application of these two methods can produce meaningful, useful data that are sensitive to the complexity and contextuality of cognitive activity, and that can support the critical comparison of competing theories of conceptual change.

Who to Contact:
Nathaniel Brown