Table 7. Analysis of the results with the Friedman test.

	CNI-GWO	NI-GWO	DO	ABC	HHO	SCA	FA	BA
Sample size	20	20	20	20	20	20	20	20
Median	0.9989	0.9984	0.7936	0.7957	0.8384	0.7529	0.8384	0.7677
Sum of ranks	154	146	73.5	88	74	41	76	67.5
Mean of the ranks	7.7	7.3	3.675	4.4	3.7	2.05	3.8	3.375
χ2-score	90.832836
Degrees of freedom (statistics)	7
p-value	6.66E−16

Notes.

The result is very siginificant at p < 0.05.