How does Netflix recommend movies? Matrix Factorization

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A friendly introduction to recommender systems with matrix factorization and how it's used to recommend movies in Netflix.
Accompanying Notebook by Yannet Interian: https://github.com/yanneta/pytorch-tu...

Gradient descent video mentioned at the end:    • A friendly introduction to Deep Learn...  

What is Machine Learning: (0:05)
How do recommendations work - Netflix example (0:40)
How to figure out dependencies - Matrix Factorization (7:35)
Matrix Factorization Benefits 20:38 How to find the right factorization (16:03)
Error Function for factorization (26:35)
How to use the factors to predict ratings - Inference (30:14)

(Thanks for the timings, Samarth Piano Posts!)