Ever wondered why some movie recommendations just don't hit the mark?
Collaborative filtering
Ever wondered why some movie recommendations just don't hit the mark?
Imagine you're planning a movie night with friends, but the streaming service keeps suggesting films you've already watched or don't like.
Collaborative filtering tries to guess your next favorite movie by looking at what similar friends liked, but if you don't have many ratings, it's like guessing without enough clues.
Example
You liked 'Inception' and 'Interstellar', but the service only knows your preferences for 'Inception' because you rated it highly, and it suggests 'Interstellar' again, even though you haven't rated it yet.
Remember this
Data sparsity in collaborative filtering can lead to inaccurate recommendations because there's not enough information to make a good guess.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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