We evaluate the performance of the SVDD based on its ability to correctly classify new (ie., test, not seen during training) sensor response vectors as due to normal or anomalous gas compositions. The performance of the SVDD is summarized by the confusion matrix in Fig. and performance metrics of precision, recall, and F1 score (0.64, 0.70, and 0.67, respectively). (See Sec. 4.3.3.) False alarms harm precision, while false negatives harm recall; the F1 score is the harmonic mean of precision and recall.