Patent US 7,979,445

A computer-implemented system provides a browse tree in which items represented within a database are arranged within a hierarchy of item categories. Each time a user selects an item, an amount of credit is cumulatively assigned to the ancestor nodes (categories) of the selected item. The amount of credit assigned to a particular category of the browse tree over time for a given user represents the user's predicted affinity for that category. The user's relative preferences for some or all of the categories are predicted by calculating differences between the user's predicted affinities for such categories and the predicted affinities of a population of users for such categories. Scores reflective of these relative category preferences are used to provide personalized recommendations or other personalized content to the user.