Area Under Curve
The area under curve (AUC) statistic is an empiricalmeasure of classification performance based on the area under an ROCcurve. It evaluates the performance of a scoring classifier on atest set, but ignores the magnitude of the scores and only takestheir rank order into account. AUC is expressed on a scale of 0 to1, where 0 means that all negatives are ranked before all positives,and 1 means that all positives are ranked before all negatives. See ROC Analysis.