Table 2. Performance indexes across new compounds in external validation.

Model	Method	Compounds/ Interactions	Cell lines	TP	TN	Coverage1	TP_C2	TN_C2
1	SVM	11202 / 26135	758	0.610	0.663	100%
2	Similarity-based (0.20)			0.572	0.574	91.76	0.617	0.551
3	Similarity-based (0.25)			0.376	0.765	65.5	0.550	0.673
4	Similarity-based (0.30)			0.260	0.843	47.56	0.515	0.722
5	Similarity-based (0.20) and SVM			0.617	0.551	100%
6	Similarity-based (0.25) and SVM			0.661	0.700	100%
7	Similarity-based (0.30) and SVM			0.523	0.656	100%

Notes: 1) Coverage: the amount of compounds in which at least one prediction was made with similarity-based approach. 2) TP_C and TN_C are the true positive and true negative evaluated only in the portion of compounds covered by similarity-approach.