An investigation of the knowledge structures of experts,intermediates and novices in physics

The literature on the role of models and theories in physics suggests that multiple models, abstract or concrete exist for a particular phenomenon. These models could be organized into hierarchies describing the entire physics domain (Giere 1994). Hierarchies of concepts have been used in other domains with success; however, criteria for a hierarchy of models in physics and theory's role are unclear. Therefore, research was conducted to describe the knowledge structures of experts, intermediates, and novices. A reiterative categorization task required subjects to sort and re-sort physics problems. The proportions of theory- and model-based categories created by the subjects were compared. Novices created hierarchies of model-based categories. Both intermediates and experts created theory-based categories at the highest, most abstract, level but combined model- and theory-based categories at middle and lower levels. These results support a representation of physics knowledge in which a hierarchy of models is organized by theory-based categories.