Fig. shows a realization of a test data set, as sensor response vectors scattered in sensor response space and colored according to the true condition in the fruit ripening room (normal or various anomalies) that produced the response. Compare the test response vectors with the SVDD decision boundary in Fig. . Many responses to anomalous conditions lie outside of the SVDD decision boundary, thus are correctly recalled as anomalies. But, some responses to anomalous conditions (particularly, responses to C 2 H 4 off anomalies) lie inside the decision boundary and go undetected. Further, we observe some false alarms-responses to normal conditions falling outside the SVDD decision boundary.