Table 3.

The result of DB coverage

The DB coverage of the molecular scaffolds [$X_Y^m$, (%)]
NCDBs (Y)	Level 0 ($X_Y^0$)	Level 1 ($X_Y^1$)	Level 2 ($X_Y^2$)	Level 3 ($X_Y^3$)
KNApSAcK	99.95	75.70	43.08	12.79
IBScreen	99.96	79.49	22.07	3.43
NPACT	100.00	80.67	54.31	18.13
Specs	99.88	85.78	64.69	33.29
TCM	99.98	74.39	34.99	13.38
NPASS	99.97	72.24	37.52	13.10
Avg. performance	99.96	78.05	42.77	15.69

The natural compound databases (NCDBs) coverage defined by Eqs. (2) and (3) are summarized at different scaffold levels

“NCDBs” means Natural Compound Databases. “Avg. performance” means the average value of performance