A Meshless WCSPH Boundary Treatment for Open-Channel Flow over Small-Scale Rough Bed

Table 3

Statistical value of empirical formulae from EPR-MOGA.

Formulae	Candidate variables							Complexity		Accuracy
	hdp	ksdp	s	hks	h			Xi	Aj	SSE	CoD
Equation (17)	−	—	+	−	+	+	+	6	4	0.34	0.88
Equation (18)	—	−	+	−	+	+	—	6	2	1.03	0.77
Equation (19)	—	−	+	—	—	+	+	4	3	0.28	0.86

X_i and A_j denote the number of independent variables and term number, respectively. SSE and CoD denote the sum of squared errors and determining coefficient, respectively. The symbols +, −, and / denote positive correlation, negative correlation, and no-correlation between the dependent variable and the independent variables, respectively.