1. A computer system for identifying potential community members, the system comprising: a data store that identifies objects of different types and relationships between objects of different types, one type of object representing a person, each relationship having an associated time; component that extracts features relating to each person from the objects and their relationships, the extracted features representing evolution of the features over time; a generate training data component that generates training data having a label associated with a person, the label indicating potential to be a community member; and a train classifier component that trains a classifier using the training data to classify the potential for a person represented by their features to be a community member.