Table 7.

Descriptive statistics for all models.

Model	Level	Mean	Standard deviation	Mean + sd, Mean - sd	Max, Min	Range (Max-Min)	Range of classification
Linear	T0	−0.879	0.702	−0.176, 0.702	−0.138, −2.289	2.150	≤−0.176
	T1	1.272	0.284	1.556, 0.284	1.761, 0.939	0.821	0.177–1.556
	T2	1.900	0.479	2.379, 0.479	2.572, 1.205	1.368	1.557–2.379
	T3	2.515	0.390	2.904, 0.390	3.089, 2.144	0.945	≥2.38
Two factorial	T0	0.466	0.371	0.836, 0.095	1.417, 0.032	1.386	≤ 0.095
	T1	1.088	0.319	1.408, 0.769	1.635, 0.567	1.068	0.096–1.408
	T2	1.708	0.714	2.421, 0.994	3.269 1.027	2.241	1.409–3.141
	T3	2.174	0.968	3.142, 1.207	4.315, 1.254	3.061	≥3.142
Quadratic	T0	−7.590	3.944	−3.646, −11.533	−1.593, −12.412	10.819	≤−3.646
	T1	−1.056	2.882	1.826, −3.939	1.190, −7.024	8.214	−3.647–1.826
	T2	0.416	1.712	2.129, −1.296	2.314, −4.055	6.369	1.827–2.418
	T3	1.167	1.252	2.419, −0.085	2.891, −1.648	4.539	≥2.419
Cubic	T0	−6.857	2.900	−3.956, −9.757	−1.040, −9.852	8.812	≤−3.956
	T1	0.619	3.536	4.156, −2.917	6.692, −7.450	14.142	−3.957–1.952
	T2	2.174	2.682	4.856, −0.508	9.562, 0.054	9.508	1.951–2.897
	T3	2.139	0.759	2.898, 1.380	3.457, 1.111	2.347	≥2.898
Quartic	T0	4.274	3.020	7.294, 1.255	6.900, −2.858	9.758	≥4.274
	T1	2.643	1.857	4.500, 0.786	5.700, 0.856	4.844	4.275–2.100
	T2	1.975	1.574	3.549, 0.401	5.700, 3.549	4.991	≤2.727
	T3	2.727	1.436	4.163, 1.291	6.200, 4.163	4.833	2.101–2.727
Fifth	T0	4.859	3.476	8.335, 1.383	9.782, 0.331	9.451	≥4.859
	T1	1.608	3.144	4.752, −1.536	8.032, −2.617	10.649	4.860–2.614
	T2	0.421	2.580	3.000, −2.159	3.313, −5.461	8.774	≤0.421
	T3	2.615	5.711	8.326, −3.097	11.095, −4.374	15.469	2.615–0.420