The claimed subject matter relates to an architecture that can identify, store, and/or output local contributions to a rank of a vertex in a directed graph. The architecture can receive a directed graph and a parameter, and examine a local subset of vertices (e.g., local to a given vertex) in order to determine a local supporting set. The local supporting set can include a local set of vertices that each contributes a minimum fraction of the parameter to a rank of the vertex. The local supporting set can be the basis for an estimate of the supporting set and/or rank of the vertex for the entire graph and can be employed as a means for detecting link or web spam as well as other influence-based social network applications.