Technical Reports

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UBC CS TR-93-51 Summary

High-Speed Visual Estimation Using Preattentive Processing, March 3, 1993 Christopher G. Healey, Kellogg S. Booth and James T. Enns, 27 pages

A new method is presented for performing rapid and accurate numerical estimation. It is derived from principles arising in an area of cognitive psychology called preattentive processing. Preattentive processing refers to an initial organization of the human visual system based on operations believed to be rapid, automatic, and spatially parallel. Examples of visual features that can be detected in this way include hue, intensity, orientation, size, and motion. We believe that studies from preattentive vision should be used to assist in the design of visualization tools, especially those for which high speed target, boundary, and region detection are important. In our present study, we investigated two known preattentive features (hue and orientation) in the context of a new task (numerical estimation) in order to see whether preattentive estimation was possible. Our experiments tested displays that were designed to visualize data from simulations being run in the Department of Oceanography. The results showed that rapid and accurate estimation is indeed possible using either hue or orientation. Furthermore, random variation of one of these features resulted in no interference when subjects estimated the numerosity of the other. To determine the robustness of our results, we varied two important display parameters, display duration and feature difference, and found boundary conditions for each. Implications of our results for application to real-word data and tasks are discussed.

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