1. A non-transitory computer readable medium having stored therein data representing instructions executable by a programmed processor for identifying a user profile from a single source with multiple users and multiple user profiles, the storage medium storing instructions operative for: identifying clusters of behavior from the multiple users of a single source using a session identification cookie to analyze a browsing history using tail sites and not using head sites to improve differentiation of clusters; analyzing each of the clusters using a profile prediction model with a second cookie that stores the profile prediction model at the single source, the second cookie different from the session identification cookie; developing a profile for each of the clusters from the session identification cookie based on the analysis of the clusters with the second cookie, wherein each of the multiple users are associated with one or more of the clusters; monitoring behavior at the single source to identify one of the clusters based on the behavior, wherein the identified cluster is associated with one of the users of a developed profile for that identified cluster; updating the profile prediction model based on the monitored behavior; and targeting content based on the developed profile for that identified cluster.