Model

In performing a regression analysis, the objective is to fit an equation (referred to as the model) to the data such that the error between the values predicted by the equation and the actual observed values is minimized. The model can have a constant Term, linear terms, and nonlinear terms.

(Linear model R = a1 + a2F1 + a3F2 + e)

(Interaction model R = a1 + a2F1 + a3F2 + a4F1F2 + e)

(Quadratic model R = a1 + a2F1 + a3F2 + a4F1F2 + a5F1^2 + a6F2^2 + e)