Table 2.

Classwise performance measures

Sensitivity, recall, true positive rate	$=\frac{\text{TP}}{\text{TP}+\text{FN}}=\frac{\text{TP}}{n^{+}}$	Specificity, true negative rate	$=\frac{\text{TN}}{\text{TN}+\text{FP}}=\frac{\text{TN}}{n^{-}}$
Positive predictive value, precision	$=\frac{\text{TP}}{\text{TP}+\text{FP}}$	Negative predictive value	$=\frac{\text{TN}}{\text{TN}+\text{FN}}$
False positive rate, fallout	$=\frac{\text{FP}}{\text{FP}+\text{TN}}=\frac{\text{FP}}{n^{-}}$	False discovery rate	$=\frac{\text{FP}}{\text{FP}+\text{TP}}$

TP: true positives. TN: true negatives. FP: false positives. FN: false negatives