I have a conceptual question on learning-to-rank, specifically about prediction. For training I input the groups to determine which documents should be ranked relatively to each other. But for prediction, I can’t input groups (at least not in the Python interface).
My understanding is that I would input the same type of data as with train and get back a ranking for each group. Instead, I input just the rows without group information and get back a score close to 0.5. What does that score then represent? A global rank? A score of how relevant that document is, and I can just group the predictions myself and then rank according to that score?