build basic recommendation engine
Build basic recommendation engine using R
For recommending movies for Chan using the above similarity matrix, we need to first fill the N/A where he has not rated. As first step, separate the non-rated movies by Chan and a weighted matrix is created by multiplying user similarity score (user_sim[,7]) with ratings given by other users. Next step is to sum up all the columns of the weight matrix, then divide by the sum of all the similarities for critics that reviewed that movie.