Experiment 1: Ebbinghaus Illusion: Psychometric curves

This dataset includes psychometric curves of twenty-nine participants (M = 29.38 years, SD = 5.52, 17 females). These curves were constructed by analysing response proportions at precise intervals of 0.1 degrees, showing a preference for the comparison circle being larger than the target circle. The logistic function was employed to quantify the probability (P) of perceiving the comparison circle as larger than the target circle. The color coding in the figure corresponds to the different conditions: small inducer (red), large inducer (green), and no inducer (gray).