Table 1. Predictive performance metrics for classification tree and random forest model.

Sensitivity, specificity, NPV (proportion of ‘nonsevere’ predictions that correctly matched literature rating), TSS (sensitivity + specificity − 1), and AUROC for predictive model methods applied to predict virulence of viruses within the test set. Random forest diagnostics indicate mean values across 200 training/test partitions. Supporting data are available via figshare: 10.6084/m9.figshare.7406441.v3 (https://figshare.com/articles/Data_and_supporting_R_script_for_Tissue_Tropism_and_Transmission_Ecology_Predict_Virulence_of_Human_RNA_Viruses/7406441/3).

Model	Sensitivity	Specificity	NPV	TSS	AUROC
Classification tree	0.625	0.826	0.864	0.451	0.636
Random forest	0.776	0.935	0.924	0.712	0.955

Abbreviations: AUROC, area under the receiver operating characteristic curve; NPV, negative predictive value; TSS, true skill statistic.