1. A method executed on a computing device for graph-based classification using entity relationships, the method comprising: determining one or more relationships of an entity with other related entities in a hierarchical structure; updating a graph structure representing a group of entities including the entity and relationships between the entities; computing an improved classification for the entity based on the updated graph structure; computing an improved classification for another entity that includes the entity based on the updated graph structure and the entity's improved classification; and updating global model parameters based on the inferred classifications in an iterative manner until a performance change from one iteration to a next iteration is less than a predefined threshold.