7. The system of claim 1 wherein the document is a status update.
1. A system for selectively delivering an article, comprising: a communications interface configured to: receive a user preference; and receive a document; a processor configured to: identify a plurality of entity pairs each comprising a concept included in a concept taxonomy and a textual representation relating to the concept included in the document, each concept having a corresponding category vector including a plurality of adjacent nodes of the concept in a taxonomy; compute a document vector (dv) for the document as a sum of the category vectors for the plurality of entity pairs; select a subset of concepts from the plurality of entity pairs according to a comparison of the document vector and the category vectors of the concepts of the plurality of entity pairs by: calculating a similarity score ds for each concept according to ds=dv·cv, where dv is the document vector and cv is a concept vector; selecting the subset of concepts as concepts having similarity scores ds with respect to the document vector hi her than a threshold; categorize the document based at least in part on the selected subset of concepts; and determine that the selected subset of concepts corresponds to the user preference; in response to determining that the selected subset of concepts corresponds to the user preference, notify a user associated with the user preference of the document; and a memory coupled to the processor and configured to provide the processor with instructions.