Both options are valid depending on how we set the PolynomialFeatures.
Now, I guess that you guys don’t want a specific setting and might then want to explicit “…a by default polynomial feature extraction…”
You are right, I guess we overlooked this detail as this would not be a normal user case. Unless you are looping over the polynomial degrees (or maybe other user cases I cannot think of right now) it does not make sense to call the polynomial feature extraction step to fit a straight line.
Another possible rephrasing of the question could be:
Is the prediction function of this pipeline on a dataset with a single input feature always a straight line?
The word “always” makes all the difference.
Can you do an issue and a PR for this? Don’t forget to label the issue with the appropriate fun labels to track it’s fix in the mooc.
Done!