ROC (receiver operating characteristic) curve - Sensitivity vs. specificity
Analysed was the question whether to predict iron deficiency in newborns the hemoglobin concentration of the blood (Hb) or the retiulocyte-hemoglobin (CHr) would be the better marker. The reticulocyte-hemoglobin was significantly better, which can be explained with physiology. If there was already anemia, Hb was slightly better (left lower corner).