Sum of square residuals as a function of galaxy stellar mass. Each panel considers a different galaxy class. Residuals between the real and the predicted distributions are shown with green lines, i.e. S^pred in Eq. (6). Residuals between the real and the recovered distributions are shown with violet lines, i.e. S^rec in Eq. (7). The residuals between the real and the recovered distributions when we use a stellar mass-dependent confusion matrix are shown in orange. Note that the y-axis scale varies from panel to panel.