Cork Stopper Quality (N = 150). (a) Percent distribution of total defective area [px] by cork stopper quality levels, overlaid with cutpoints (purple dashed lines) selected with the Total Accuracy criterion from cumulative ROC curves. (b) Cumulative ROC curves (focused on upper-left quadrant) indicating coordinates for Total Accuracy cutpoints: poor vs. normal, superior quality (green) and poor, normal vs. superior (orange).