notation_standards.rst

Notation standards, References

In the documentation, you will find the following notation:

• R : the set of all ratings.
• R_train, R_test and R̂ denote the training set, the test set, and the set of predicted ratings.
• U : the set of all users. u and v denotes users.
• I : the set of all items. i and j denotes items.
• U_i : the set of all users that have rated item i.
• U_ij : the set of all users that have rated both items i and j.
• I_u : the set of all items rated by user u.
• I_uv : the set of all items rated by both users u and v.
• r_ui : the true rating of user u for item i.
• r̂_ui : the estimated rating of user u for item i.
• b_ui : the baseline rating of user u for item i.
• μ : the mean of all ratings.
• μ_u : the mean of all ratings given by user u.
• μ_i : the mean of all ratings given to item i.
• σ_u : the standard deviation of all ratings given by user u.
• σ_i : the standard deviation of all ratings given to item i.
• N_i^k(u) : the k nearest neighbors of user u that have rated item i. This set is computed using a similarity metric <surprise.similarities>.
• N_u^k(i) : the k nearest neighbors of item i that are rated by user u. This set is computed using a :pysimilarity metric <surprise.similarities>.

References

Here are the papers used as references in the documentation. Links to pdf files where added when possible. A simple Google search should lead you easily to the missing ones :)

refs.bib