A repository contains objects including facts about entities. Some objects might be associated with the same entity. An object merge engine identifies a set of merge candidate objects. A grouping module groups the merge candidate objects based on the values of facts included in the objects. An object comparison module compares pairs of objects in each group to identify evidence for and/or against merging the pair. Evidence for merging the pair exists if, e.g., the objects have a type in common or share an uncommon fact. Evidence against merging the pair exists if, e.g., the objects have differing singleton attributes. A graph generation module generates graphs describing the evidence for and/or against merging the pair. A merging module analyzes the graphs and merges objects associated with the same entity. The merged objects are stored in the repository.