Fig. 5.

Accuracy and precision for the identification of 11 volatile organic compounds (VOCs) based on the signals obtained from the hybrid gel films with distinct thicknesses. a) Chemical structures of the 11 VOCs used in this study. b) Overall accuracy and precision. c) Correct prediction of the support vector machines (SVM) classifier for the hybrid gel films with different thicknesses. d) Confusion matrix for SVM, illustrating the prediction results regarding 11 VOCs for the 30-μm-thick and e) 60-μm-thick hybrid gel films. Blue squares in the diagonal represent the correct predictions made by the classifier, and gray squares represent the incorrect predictions.