21. The non-transitory computer-readable medium of claim 20 , wherein the method further comprises: determining which of the first anomaly detection score and the second anomaly detection score is higher; and outputting the input dataset based on the anomaly detection score that is higher.
20. The non-transitory computer-readable medium of claim 19 , wherein the method further comprises: determining a first plurality of appearance frequencies corresponding to the first plurality of distinct training n-grams; and determining a second plurality of appearance frequencies corresponding to the second plurality of distinct training n-grams; and determining a first anomaly detection score based on the first plurality of appearance frequencies and a second anomaly detection score based on the second plurality of appearance frequencies.