How do you find the interaction between a continuous and a categorical variable? I have tried using
ggPredict but it doesn't seem to work if there are more levels.
I have a categorical variable as reputation which has 7 levels also I have multiple variables to predict the marks of a student in the next exam of masters eg age, pref_hand, height, exam 1, exam 2, exam 3. How can I find the interaction of the reputation with the best model which I found using forward step regression for predicting the marks in the next exam and make changes to my model if I find interaction?
I have tried using
scatterPlotMatrix but the colors are getting recycled and it's hard to find any pattern plus I don't even know if the interaction is statistically significant