Table 3. User-defined parameters for the ELM, ANN and GP models.

ELM		ANN		GP
Number of layers	3	Number of layers	3
Neurons	Input: 3; Hidden: 3, 6, 10; Output: 1	Neurons	Input: 3; Hidden: 3, 6, 10; Output: 1	Neurons	Output: 1
		Number of iteration	1000	Population size	512
		Activation function	Sigmoid Function	Function set	+,-,×,÷,√, ln, $\stackrel{x}{e},\stackrel{x}{a}$
Learning rule	ELM for SLFNs	Learning rule	Back propagation	Head size	5–9
				Chromosomes	20–30
				Number of genes	2–3
				Mutation rate	91.46
				Crossover rate	30.56
				Inversion rate	108.53