FastofD: Contextual data cleaning with ontology functional dependencies

Functional Dependencies (FDs) define attribute relationships based on syntactic equality. As a result, FD-based data cleaning systems incorrectly label syntactically different but semantically equivalent values as errors. To address this problem, we demonstrate FastOFD: a system for discovering Ontology Functional Dependencies (OFDs) which express semantic attribute relationships such as synonyms and is-a hierarchies defined by an ontology In addition to discovering OFDs, FastOFD generates suggestions for repairing erroneous data, and we demonstrate that FastOFD significantly reduces the number of false positive errors compared to FD-based data cleaning techniques.