Collaborative Filtering, Matrix Factorization, Recommender Systems, Gradient Descent, Neural Networks.
shape (|U|, |V|) Finally, R_hat is the reconstructed ratings The linear version of R_hat is created my matrix multiplying U and V, which is equivalent to a series of U and V vector dot products. The non-linear version uses a non-linear function in-place of the dot product. In our case, this will be