Poggendorff Illusion

The purpose of this experiment is to measure how the magnitude of the Poggendorff illusion is affected by changes in the separation of the vertical line components and changes in the length of the diagonal line components. Twenty-four randomly ordered trials are used to obtain 4 replicate measures under the 6 experimental conditions shown below. On each trial, users drag the upper right diagonal to a position that appears collinear with a lower right diagonal.  The dependent measure is the degree of misalignment of these diagonal line segments in pixels.

Separation of Verticals

Length of diagonals Narrow Medium Wide

Short

Long

Begin the Poggendorff Illusion Experiment                  Download Authorware Source Files


Download Poggendorff Data Files

 

Last revised:January 22, 2010 08:58:34 AM
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