Figure 4
From: Individualistic weight perception from motion on a slope

Group-average measurements showing (a) psychometric functions and (b) derivatives of the psychometric functions. The abscissas represent different weight values used in the experiment. The ordinates in (a) denote the proportion of trials (normalized percentage) in which the group perceived the comparison stimulus as heavier than the base stimulus. Red circles represent the proportion of trials for each weight value where participants perceive the comparison stimulus as heavier than the base stimulus. Orange circles represent the average just noticeable difference, where the participants started to notice the difference in motion. Error bars represent standard deviation for each weight value. The ordinates in (b) denote derivative values. The position of the peak indicates just noticeable difference similar to (a). The dashed lines and blue highlights depict full width at half maximum (FWHM). Note that the FWHM corresponds directly to the weight selection performance. The higher the performance in distinguishing the weight from motion, the smaller the FWHM.