A digital media system models social categories of a virtual identity. The system, defines a plurality of modeling categories according to the virtual identity and models a degree of a membership in a category for a member of the category. Each category has a feature shared in varying degrees by one or more members of the category. The system simulates changes to the membership and determines a naturalization trajectory having a change of the degree of membership in a category over time of the virtual identity. The degree of membership includes a gradient value in a category feature and an interface configured to represent a category membership that dynamically changes as category membership changes.