Mean normalization and movie rating logic

Hello everyone,

This is perhaps a philosophical/semantics question but I was just wondering about this whole approach of designating ratings for someone who had not provided any ratings before (as discussed in the video).

More specifically, I can understand the mathematical footwork to provide starting guesses for Eve in the example provided.
However, is it not a stretch to assume that we have sufficient intuition about someone when there is absolutely no record of any rating? I would hate being bunched up with the average when my movie tastes might be very different to the mean.
Perhaps this is really just a starting point when you have nothing else to go on but this assumption still leaves me uncertain.

What to you think?


So when collaborative filtering can’t give us any better insights into one’s perference, we might want to go for the content-based recommendation option that will make use of any initial knowledge about the user. However, there is always a limit.