Reddit mentions of Recommender Systems: The Textbook

I would also recommend the coursera Recommender System Specialization at it's a very good introduction course to all the main concepts about Recommender System https://www.coursera.org/specializations/recommender-systems

I like the content of the course and the explanation given by both Konstan and Ekstrand. Nevertheless, what I don't like about the specialization is about how the course is actually managed, the community/forum of the course is very quiet. Mentors aren't much available to help and there is some "bugs" that are still not resolved concerning the course for a while now.

There is also some text books you can start with, like "Recommender Systems Textbook by Charu Aggarwal" https://www.amazon.fr/Recommender-Systems-Textbook-Charu-Aggarwal/dp/3319296574

Further you can start reading papers submitted to the ACM Conference Series on Recommender System to follow state-of-the-art techniques https://recsys.acm.org/

To summarize, mastering recommender systems requires lots of work and reading as it's relatively a new research field compared to other fields under the Information Retrieval umbrella.

Recsys is a broad subject, on the top of my mind:

Have a look at Xavier Amatriain MLSS lecture in 2014:

• https://youtu.be/bLhq63ygoU8
  
• https://youtu.be/mRToFXlNBpQ
  
  This book does a broad survey: https://www.amazon.fr/Recommender-Systems-Textbook-Charu-Aggarwal/dp/3319296574
  
  maybe look at models implemented in spotlight: https://github.com/maciejkula/spotlight
  
  Finally, look at recent Recsys papers, this should get you started.
  
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