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Open Access

Document Type


Degree Program


Degree Type

Master of Science (M.S.)

Year Degree Awarded


Month Degree Awarded



Category Construction, Modeling


Three experiments examined category creation with no feedback and minimal feedback by using modeling to determine number of dimensions subjects attended to. In the first experiment, subjects were shown a series of two-dimensional objects with no training and no feedback and asked to categorize the stimuli. Subjects in experiment 1 mostly attended to one dimension. In the second experiment, subjects shown similar two-dimensional stimuli but were given minimal feedback. Significantly more subjects in experiment 2 attended to both dimensions. In the third experiment, subjects were trained on three related two-dimensional categories and then asked to categorize four. Performance in experiment 3 was similar to that of experiment 1, where subjects mainly attended to 1 dimension. These findings indicate that a more natural feedback structure would help subjects create categories that resemble those used in everyday life.


First Advisor

Andrew L. Cohen