Polynomial Regression

Question 1

Centre the predictor variable

Answer 1

(cx) subtracting the mean of the predictor variable from each value of the predictor variable. Allowing for more stable model fitting.

Question 2

Difference of polynomial regression to multiple regression.

Answer 2

Polynomial regression is fitting of a curved line model to a dataset with only 1 type of predictor variable. Compared to fitting a line to multiple predictor values.