#rmse

Question 1: Select all that apply

Which statements about content-based filtering, as a set of per-user regression models on item features, are true? Select all that apply.

Content-based filtering uses item features in addition to the similarity between users1
Content-based filtering represents each user in terms of the known features of the items they rated2
In this setup, a new movie with no ratings yet cannot be given predicted ratings3
If one user has ratings in the training matrix but none in the validation matrix, the validation RMSE cannot be computed4