• Implicit Recommender Systems: Biased Matrix Factorization

  Blog post that describes recommendation systems that can account for user & item biases, as well as deal with implicit user feedback as opposed to explicit user ratings of products.

• Recommendation Systems using Collaborative Filtering, Andrew Ng

  Set of really clear videos giving overview of the theory behind recommendation systems.

Tools

• LightFM LightFM is a Python implementation of a number of popular recommendation algorithms for both implicit and explicit feedback.

Other

• GroupLens

  Active ML research group led by Joe Konstan amongst others at University of Minnesota. Both blogs and publications are worth checking out.

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