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More detailed results will be seen after the main results:
In this window, the results in each of the 4 main conditions are subdivided into those trials where the subject sets (at the end of the trial) the comparison line to be either 1) longer than the standard line, 2) shorter than the standard line, or 3) equal to the standard line. These results are interesting because they give us more information about the effect of the illusion.
For example, in the different arrowhead condition, we see that the effect of the illusion was to cause the subject to always set the comparison line longer than the standard, independent of the type of trial. Thus the effect of the illusion is make the comparison line look longer than it really is. If you go back the Müller-Lyer description page , you'll see that this is the typical effect. You also notice in this example that while it was sometimes possible to set the two lines to be equal in the control condition (i.e., twice in the same arrowhead, ascending condition and once in the same arrowhead, descending condition), it was not possible to set the two lines to be equal in the experimental (different arrowhead) condition.
So: what sorts of results will you get--and why? Try the experiment and see!