Molecules 2016, 21, 1554 16 of 20 RMSE = 1 n ∑ (y − yˆ)2 (6) Q2 = 2 ∑ (y − y)(yˆ − yˆ) ∑ (y − y)2∑ (yˆ − yˆ)2 (7) R2 = 1 − ∑∑ (y (y − − yˆ)2 y)2 (8) Here, n is the number of samples...