1. A method performed by a computing system including a processor and a memory for analyzing user behavior information, comprising: receiving a stream of user behavior information, wherein the received stream of user behavior information comprises a request from a particular user for a web page; augmenting a representation of user behavior in accordance with the received stream of user behavior information, the representation comprising a sparse matrix of user behavior facts, wherein the augmentation is performed solely in response to the request from the particular user for the web page and comprises— in response to receiving the stream of user behavior information, creating an entry in the sparse matrix comprising details of the request; placing a first pointer to the created entry in a chain of pointers corresponding to the user; and placing a second pointer to the created entry in a chain of pointers corresponding to the request; and analyzing the sparse matrix to obtain an analysis result for the stream of user behavior.