Confusion matrix summarizing the performance of our new diagnostic tool on the test set (Sect. 3.2) of our final sample (Sect. 2.4). We see that almost all objects are found on the primary diagonal indicative of a high-performance classifier. There are a few objects in the off-diagonal elements (misclassifications), indicating mild mixing between the composite and star-forming (SF) and composite and LINER classes. This is expected, as these classes share common characteristics.