Welcome to your interview.
The question is on your right: Evaluate a Recommendation System. Take a moment with it first.
Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes). Discussion and graded submissions share your five interviewer interactions, so spend them well.
You are evaluating a recommendation system for a content platform. The model ranks items for the home feed, and the team wants to know whether it is actually better than the current approach.
How would you evaluate the performance of a recommendation system?