Schema / ontology matching is the task of finding semantic correspondences between elements of two schemas or two ontologies. It is needed in many metadata-intensive applications, such as integration of web data sources, catalog integration/merging, data warehouse loading,  XML message mapping and peer-to-peer data management. Currently, such matching tasks are largely performed manually by domain experts, and therefore they are time-consuming, tedious and error-prone. Approaches for automating the schema and ontology matching tasks as much as possible are needed to simplify and speed up the development, maintenance and use of metadata-intensive applications.

Our contributions to semi-automatic schema and ontology matching are as follows:

• Develoment of a solution taxonomy of the major approaches to semi-automatic schema matching (VLDB Journal 2001, VLDB 2001)
• Development of a new graph-based structural matcher called Similarity Flooding (Best Student Paper, ICDE 2002). A prototypical implementation is available including source code.
• Development of the COMA and COMA++ platforms to combine different match approaches in a flexible way and to reuse previously determined match results (VLDB 2002, SIGMOD2005, IS2007).
• Comprehensive evaluation of different match techniques based on precision, recall and a new combined metric, called Overall (ICDE 2002, VLDB 2002, LNCS2593, IS2007))
• Investigation of instance-based methods for schema and ontology matching and their succesful use for solving large-scale match tasks (e.g., matching of life science ontologies, product catalogs, and web directories).

Publications

Arnold, Patrick; Rahm, Erhard Enriching Ontology Mappings with Semantic Relations Data and Knowledge Engineering, Volume 93, September 2014, Pages 1–18, Best DKE paper of 2014 2014-09

Arnold, P.; Rahm, E. Extracting Semantic Concept Relations from Wikipedia Proc. 4th Int. Conf. Web Intelligence, Mining and Semantics (WIMS) 2014-06

Arnold, Patrick; Rahm, Erhard Semantic Enrichment of Ontology Mappings: A Linguistic-based Approach Proc. 17th ADBIS Conference. LNCS 8133, pp. 42-55 2013-09

Arnold, Patrick Semantic Enrichment of Ontology Mappings: Detecting Relation Types and Complex Correspondences 25. GI-Workshop Grundlagen von Datenbanken 2013

Raunich, S.; Rahm, E. Towards a Benchmark for Ontology Merging Proc. 7th OTM Workshop on Enterprise Integration, Interoperability and Networking (EI2N’2012), Springer LNCS 2012-09

Massmann, Sabine; Raunich, Salvatore; Aumueller, David; Arnold, Patrick; Rahm, Erhard Evolution of the COMA Match System OM-2011 (The Sixth International Workshop on Ontology Matching, October 24th, 2011, Bonn, Germany) 2011-10

Algergawy, A.; Massmann, S.; Rahm, E. A Clustering-based Approach For Large-scale Ontology Matching Proc. ADBIS Conf. 2011, LNCS 6909, pp. 415-428 2011-09

Groß, A.; Hartung, M.; Kirsten, T.; Rahm, E. Mapping Composition for Matching Large Life Science Ontologies 2nd International Conference on Biomedical Ontology (ICBO 2011) 2011-07

Peukert, E.; Eberius, J.; Rahm, E. AMC – A Framework for Modelling and Comparing Matching Systems as Matching Processes Proc. Int. Conf. on Data Engineering (Demo paper), 2011 2011-04

Raunich, Salvatore; Rahm, Erhard ATOM: Automatic Target-driven Ontology Merging Proc. Int. Conf. on Data Engineering (Demo paper), 2011 2011-04

Peukert, Eric; Rahm, Erhard Restricting the Overlap of Top-N Sets in Schema Matching Proc. EDBT workhop on New Trends in Similarity Search (NTSS 2011) 2011-03

Groß, A.; Hartung, M.; Kirsten, T.; Rahm, E. On Matching Large Life Science Ontologies in Parallel 7th International Conference on Data Integration in the Life Sciences (DILS 2010) 2010-08

Peukert, Eric; Berthold, Henrike; Rahm, Erhard Rewrite Techniques for Performance Optimization of Schema Matching Processes 13th International Conference on Extending Database Technology, EDBT 2010 2010-03

Massmann, S. ; Rahm, E. Evaluating Instance-based Matching of Web Directories 11th International Workshop on the Web and Databases (WebDB 2008) 2008-06

Drumm, C.; Schmitt, M.; Do, H.-H.; Rahm, E. QuickMig - Automatic Schema Matching for Data Migration Projects Proc. ACM CIKM, Lisabon, Nov. 2007 2007-11

Engmann, D.; Massmann, S. Instance Matching with COMA++ BTW 2007 Workshop: Model Management und Metadaten-Verwaltung 2007-03

Do, H.-H.; Rahm, E. Matching Large Schemas: Approaches and Evaluation Information Systems, Volume 32, Issue 6, September 2007, Pages 857-885 2007

Massmann, S.; Engmann, D.; Rahm, E. COMA++: Results for the Ontology Alignment Contest OAEI 2006 International Workshop on Ontology Matching, collocated with the 5th ISWC-2006; Athens, Georgia, USA 2006-11

Do, Hai Hong Schema Matching and Mapping-based Data Integration Dissertation. Veröffentlich durch Verlag Dr. Müller (VDM), ISBN 3-86550-997-5, 2006

Aumueller, D.; Do, H.H.; Massmann, S.; Rahm, E. Schema and ontology matching with COMA++ SIGMOD Conference 2005-06

Rahm, E.; Do, H.H.; Massmann, S. Matching Large XML Schemas Sigmod Record 33(4) 2004-12

Do, H.H.; Melnik, S.; Rahm, E. Comparison of Schema Matching Evaluations Proc. Workshop Web and Databases, LNCS 2593, 2003 2003

Do, H.H.; Rahm, E. COMA - A System for Flexible Combination of Schema Matching Approaches Proc. 28th Intl. Conference on Very Large Databases (VLDB), Hongkong, Aug. 2002 2002