Table 2.

Results of Stepwise regression using valve intervals, including estimated coefficients (a₀, a₁, …, a₅) and Standard Error (SE) of the coefficients, t-statistic and p-value for the F-statistic of the hypothesis of the coefficient being zero.

	Estimate	SE	t-test	p-value
Intercept	−276.810	61.772	−4.481	4.218*10−5
EDT	5.496	1.215	4.525	3.641*10−5
ICT	7.897	1.743	4.530	3.574*10−5
VFT	0.682	0.267	2.551	0.014
EDT*ICT	−0.140	0.034	−4.142	1.295*10−4
ICT*VFT	−0.017	0.007	−2.273	0.027

The model was obtained based on the parameters in milliseconds and GA in weeks. Other results include: F-statistics: 15.1, p-value = 4.36^*10⁻⁹, Standard deviation of the error distribution: 4.01 (weeks), R-squared: 60%, adjusted R-squared: 56%.