Table 2.

Evaluation measures employed in this study.

Measure	Abbreviation	Equation
Sensitivity (recall)	%SE	TP/(TP+FN)
Specificity	%SP	TN/(TN+FP)
Accuracy	%ACC	(TP+TN)/(TP+TN+FP+FN)
F-measure	%Fm	2TP/(2TP+FP+FN)
Matthews' correlation coefficient	%MCC	(TP × TN-FP × FN)/sqrt((TP+FP) × (TN+FN) × (TP+FN) × (TN+FP))

The definition of the abbreviations used: TP is the number of real pre-miRNAs detected; FN is the number of real pre-miRNAs missed; TN is the number of pseudo hairpins correctly classified; and FN is the number of pseudo hairpins incorrectly classified as pre-miRNA.