Methods and systems to enable simplified, compact implementations of profiling and other functions on STBs or other limited-resource computing platforms. For every television show transmitted from the server to the STB, the server also sends a classifying group identifier for the show. The STB then generates user profiles, ratings and/or recommendations, based on the group identifiers, simplifying the STB's processing tasks. Exception processing, special cases, or changes in group assignments or algorithms are handled at the server. The STB calculates viewing profiles based on recording statistics about content its user(s) view, based on the group identifiers. In another embodiment, the STB provides ratings and/or recommendations using group identifier information and related statistics. User privacy is maintained by stripping off and discarding personal information or averaging user profile information to erase or "blur" any suggestions of personal information.