Patent ID: 7962471

Claim:
A machine-implemented method for extrapolating profile information from user web page access patterns, comprising: detecting, in a computer system, a set of web pages accessed by a test user having an unknown user profile attribute; initializing, in the computer system, a first set of Expectation Maximization (EM) parameters with data from a training set of users having a known user profile attribute for the unknown user profile attribute of said test user; performing, in the computer system, a first EM process using said first set of initialized EM parameters to obtain a first EM process result that defines a probability of a user profile attribute given said test user; repeating the EM process based on a log-likelihood which is determined by L = ∑ g ⁢ ∑ u ⁢ n ⁡ ( s , u ) ⁢ ⁢ log ⁢ ⁢ P ⁡ ( s , u ) , wherein s corresponds to a web page, u corresponds to a respective user, g indicates gender, and n(s,u) indicates the number of times the user u has accessed the web page s; and assigning, in the computer system, said user profile attribute to the unknown user profile attribute of said test user in response to said first EM process result; wherein said first EM process is performed while assuming that the unknown user profile attribute of said test user is statistically dependent on whether said test user accesses a web page.