Table 2 The results for QSAR modelling of catechol structures using PC-LS-SVM and PC-ANFIS

Used PCs

1–6

1 AND 4

Function type

Gaussian RBF

Gaussian (input = 2, epochs = 50)

Preprocessing

–

Auto scaling

R ²_Calibration

0.950

0.84

Q ²_{LOO Cross-validation}

0.82

0.63

Q ²_{LMO(20 %) Cross-validation}

0.80

0.58

R ²_{External validation}

0.83

0.66

R ² _{Y-permutation test}

<0.2

<0.24

R ² _{Y-permutation test LOO}

<0.26

<0.3

Press_calibration

1.11

3.48

Press_{LOO Cross-validation}

3.90

8.014

Press_{LMO Cross-validation}

3.95

8.6

Press_{External validation}

1.38

7.32

Rm ²_{External Validation}

0.63 (passed)

0.4 (failed)

CCC

0.84

0.6

RMSE

0.41

0.8

MAE

0.12

0.19

K

0.984 (passed)

0.95 (failed)

K′

0.996 (passed)

0.93 (failed)