Effects of specific-level versus broad-level training for broad-level category learning in a complex natural science domain

Abstract

Category learning is a core component of course curricula in science education. For instance, geology courses teach categorization of rock types. Using the educationally authentic rock categories, the current project examined whether category learning at a broad level (Igneous, Sedimentary, and Metamorphic rocks) could be enhanced by learning category information at a more specific level (e.g., Diorite under Igneous, Breccia under Sedimentary, etc.). Experiments 1 and 2 showed that specific-level training was inferior to broad-level training when participants were required to respond at the broad level regardless of whether broad- and specific- level category labels were presented simultaneously during classification training or specific-level categories were learned initially followed by training on the specific-broad level name associations. However, Experiments 3 and 4 showed that specific-level training was as good as broad-level training when the training was more extensive and participants were allowed to respond at the trained level. By considering confusion matrices (i.e., probabilities that instances in a given category was erroneously classified as belonging to other categories), we conjectured that between-specific-level category similarity, specifically the degree to which similar-looking specific-level categories belong to the same broad-level category, is an important factor in determining the efficacy of specific-level training.