Consider the linear regression model from Exercise 12-4. Is the second-order term necessary in the regression model?

Exercise 12-4

Hsuie, Ma, and Tsai (€˜€˜Separation and Characterizations of Thermotropic Copolyesters of p-Hydroxybenzoic Acid, Sebacic Acid, and Hydroquinone,€™€™ (1995, Vol. 56) studied the effect of the molar ratio of sebacic acid (the regressor) on the intrinsic viscosity of copolyesters (the response). The following display presents the data.

Transcribed Image Text:

Ratio Viscosity 0.45 1.0 0.9 0.20 0.34 0.8 0.7 0.58 0.70 0.6 0.5 0.57 0.55 0.4 0.3 0.44