Given the data on y and x,what is needed to run Excel regression for the polynomial model of order 3?
A) Creating the values of one pseudo-explanatory variable by squaring the values of x.
B) Creating the values of two pseudo-explanatory variables by squaring and cubing the values of x,respectively.
C) Creating the values of three pseudo-explanatory variables by raising the values of x to the power of 2,3,and 4,respectively.
D) Nothing is needed.

Question

Quizplus · Accepted Answer

In order to run a polynomial regression of order 3, we need to create two pseudo-explanatory variables by squaring and cubing the values of x, respectively. This is because a polynomial regression of order 3 has the form y = b0 + b1x + b2x^2 + b3x^3, meaning we need x^2 and x^3 terms to fit the model. Creating only one pseudo-explanatory variable by squaring the values of x would only allow us to fit a polynomial regression of order 2. Creating three pseudo-explanatory variables by raising x to the power of 2, 3, and 4, respectively, is unnecessary as we only need x^2 and x^3 terms. Therefore, the best choice is B.

Given the Data on Y and X,what Is Needed to Run