Table 5. Pvalues of ttests for direction a Type of polynomial p‑values Linear [ ; ] Quadratic [ ; ; ] Cubic [0.0189 ; ; 0.0127 ; 0.23125] František Trebuňa et al. Application of Polynomial Regression Models in Prediction of Residual Stresses of a Transversal Beam. American Journal of Mechanical Engineering, 2016, Vol. 4, No. 7, 247-251. doi:10.12691/ajme-4-7-3 © The Author(s) 2015. Published by Science and Education Publishing.