Table 6 Results of the Friedman Test on the datasets and approaches.

From: A hybrid Harris Hawks Optimization with Support Vector Regression for air quality forecasting

Data

EO-SVR

GWO-SVR

HGSO-SVR

BMO-SVR

MRFO-SVR

SSA-SVR

WOA-SVR

HHO-SVR

P-value

Sigma

1001

7

1.6

5

2.9

4

6

8

1.5

2.704E−12

2.449E+00

1003

2

4.4

6.7

5.5

1

4.65

3.75

8

5.877E−11

2.448E+00

1005

2

3.5

6.1

6.9

4.8

3.7

8

1

3.743E−12

2.449E+00

1007

3.25

5

6.4

1.4

3.55

3.8

8

4.6

3.239E−08

2.439E+00

1009

3.8

5.4

7

1

3.5

5.3

8

2

7.279E−12

2.449E+00