The All-Encompassing Recall Stage

This chapter introduces the initial stage of the recommender system, known as the recall stage. The core of a recommender system lies in information filtering. Serving as the primary information filter, the recall stage sifts through vast amounts of content across multiple dimensions to identify the most relevant information that users are likely to find interesting. This filtered content is then passed on to subsequent relevance ranking technologies for further processing. The recall stage plays a crucial role in determining the upper limit of the recommender system.