Suppose that the sample regression equation of a second-order model is given by $\tilde { y } = 2.50 + 0.15 x + 0.45 x ^ { 2 }$ .Then,the value 2.50 is the:
A) intercept where the response surface strikes the y-axis.
B) intercept where the response surface strikes the x-axis.
C) predicted value of y.
D) None of these choices.

Question

Quizplus · Accepted Answer

The intercept where the response surface strikes the y-axis is the value of y when x is equal to 0. In the given equation, the coefficient of x and x^2 are both positive, which indicates a parabolic shape of the response surface. Therefore, the intercept where the response surface strikes the y-axis is the constant term 2.50.

Suppose That the Sample Regression Equation of a Second-Order Model y~=2.50+0.15x+0.45x2\tilde { y } = 2.50 + 0.15 x + 0.45 x ^ { 2 }y~​=2.50+0.15x+0.45x2

Suppose That the Sample Regression Equation of a Second-Order Model $\tilde { y } = 2.50 + 0.15 x + 0.45 x ^ { 2 }$