This paper

• Lee, M.D., & Wetzels, R. (submitted). Individual differences in attention during category learning.

which we recently submitted to the Cognitive Science conference has an interesting result. It takes a standard condensation category learning task — in which it is usually assumed people pay attention to both stimulus dimensions, because they are both relevant to learning the category structure — and applies Nosofsky’s Generalized Context Model.

A standard analysis, assuming no individual differences, gives the standard divided attention result. But a re-analysis that allows for individual differences finds two groups of subjects, half of whom attend to one dimension, half of whom attend to the other, and basically none of whom divide their attention.

The posterior distributions over attention and generalization parameters for the two groups are shown in the top panels of the picture (click the thumbnail at the top of the post to get a good view), and their posterior predictives below that show their good fit to the qualitatively different category learning behavior of the two groups. Food for thought …