Table 3.

Estimates of the Van Genuchten model parameters, $k_u$, and calibration parameters using the IES and PF methods with r values of 25, 50 and 100 for the application case with synthetic data.

Parameter	r	${\mathit{\theta }}_{\mathit{r}}$	$\mathit{\alpha }$	n	${\mathit{k}}_{\mathit{s}}$	${\mathit{k}}_{\mathit{u}}$	a	b
True value		0.067	0.02	1.41	0.0075	0.005	1.15	0.07
IES estimates	25	0.0541	0.0212	1.3542	0.0169	0.00412	1.336	0.007
	50	0.0486	0.0195	1.4197	0.0100	0.00465	1.187	0.061
	100	0.0506	0.0194	1.3933	0.0124	0.0046	1.156	0.067
PF estimates	25	0.0523	0.0107	1.3129	0.0060	0.0018	1.161	0.115
	50	0.0538	0.0132	1.7382	0.0061	0.0034	1.033	0.124
	100	0.0416	0.0022	1.6034	0.0052	0.0014	1.030	0.133