“…The collaborative filtering recommendation algorithm is the earliest and well-applied recommendation algorithm, which is used primarily for preference prediction and item recommendation. By mining a specified user's historical behavior data, the algorithm analyzes the user's interest, finds other users with similar interest in the user set, synthesizes the evaluation of these related users on certain items, forms the system's preference prediction for the items, and finally recommends items with similar interest for the user [19], [20].…”