An article entitled ?oA Method for Improving the Accuracy of Polynomial Regression Analysis’’ in the Journal of Quality Technology (1971, pp. 149–155) reported the following data on y = ultimate shear...

An article entitled ?oA Method for Improving the Accuracy of Polynomial Regression Analysis’’ in the Journal of Quality Technology (1971, pp. 149–155) reported the following data on y = ultimate shear strength of a rubber compound (psi) and x = cure temperature (°F).


(a) Fit a second-order polynomial to these data.
(b) Test for significance of regression using a = 0.05.
(c) Test the hypothesis that B11 = 0 using a = 0.05.
(d) Compute the residuals from part (a) and use them to evaluate model adequacy.