Re: [R] Plotting a cubic line from a multiple regression

[EMAIL PROTECTED] wrote in news:[EMAIL PROTECTED] uk: I'm attempting to plot a cubic relationship between two variables controlling for the effects of a third variable. In this short example, I'm trying to use AGE to predict CORTEX while controlling for the effects of TIV (total

Re: [R] Plotting a cubic line from a multiple regression

I'm attempting to plot a cubic relationship between two variables controlling for the effects of a third variable. In this short example, I'm trying to use AGE to predict CORTEX while controlling for the effects of TIV (total intracranial volume): cortex =

Re: [R] Plotting a cubic line from a multiple regression

Hi Ashish, I am rather more concerned about whether what you outlined is legitimate (your question 1 below). If you are looking at children, higher AGE will be associated with higher TIV, so both variables would essentially measure the same thing (see Miller Chapman, Misunderstanding