"Unsupervised Category Learning with Integral-Dimension Stimuli " by Shawn W. Ell, Gregory F. Ashby et al.

Psychology Faculty Scholarship

Document Type

Article

Title

Unsupervised Category Learning with Integral-Dimension Stimuli

Authors

Shawn W. Ell, University of MaineFollow
Gregory F. Ashby, University of California, Santa BarbaraFollow
Steven B. Hutchinson, University of MaineFollow

Publication Title

Quarterly Journal of Experimental Psychology

Publisher

Taylor & Francis

Publication Date

4-16-2012

First Page

1537

Last Page

1562

Issue Number

Volume Number

Abstract/ Summary

Despite the recent surge in research on unsupervised category learning, the majority of studies have focused on unconstrained tasks in which no instructions are provided about the underlying category structure. Relatively little research has focused on constrained tasks in which the goal is to learn pre-defined stimulus clusters in the absence of feedback. The few studies that have addressed this issue have focused almost exclusively on stimuli for which it is relatively easy to attend selectively to the component dimensions (i.e., separable dimensions). In the present study, we investigated the ability of participants to learn categories constructed from stimuli for which it is difficult, if not impossible, to attend selectively to the component dimensions (i.e., integral dimensions). The experiments demonstrate that individuals are capable of learning categories constructed from the integral dimensions of brightness and saturation, but this ability is generally limited to category structures requiring selective attention to brightness. As might be expected with integral dimensions, participants were often able to integrate brightness and saturation information in the absence of feedback – an ability not observed in previous studies with separable dimensions. Even so, there was a bias to weight brightness more heavily than saturation in the categorization process, suggesting a weak form of selective attention to brightness. These data present an important challenge for the development of models of unsupervised category learning.

Repository Citation

Ell, Shawn W.; Ashby, Gregory F.; and Hutchinson, Steven B., "Unsupervised Category Learning with Integral-Dimension Stimuli" (2012). Psychology Faculty Scholarship. 29.
https://digitalcommons.library.umaine.edu/psy_facpub/29

Citation/Publisher Attribution

Ell, S. W., Ashby, F. G., & Hutchinson, S.. (2012). Unsupervised category learning with integral-dimension stimuli. Quarterly Journal of Experimental Psychology, 65, 1537-1562.

Publisher Statement

This is an Accepted Manuscript of an article published by Taylor & Francis in Quarterly Journal of Experimental Psychology on April 16, 2012, available online: http://www.tandfonline.com/10.1080/17470218.2012.658821.