Building an Ontological Base for Experimental Evaluation of Semantic Web Applications

1. Building an Ontological Base for ExperimentalEvaluation of Semantic Web Applications Peter Bartalos, Michal Barla, Gyorgy Frivolt, Michal Tvarožek, Anton Andrejko, Mária Bieliková and Pavol Návrat {name.surname}@fiit.stuba.sk Institute of Informatics and Software Engineering Faculty of Informatics and information Technologies Slovak University of Technology in Bratislava

2. Motivation • Semantic Web applications Experimental Evaluation (SWEE) • Semantic annotation of the information • Searching in semantic information space • AKTORS • Knowledge Web • On-To-Knowledge • NAZOU – job offers (nazou.fiit.stuba.sk) Tools for acquisition, organization and maintenance of knowledge in an environment of heterogeneous information resources • MAPEKUS – scientific publication (mapekus.fiit.stuba.sk) Modeling and Acquisition, Processing and Employing Knowledge About User Activities in the Internet Hyperspace • Demand for well-built large scale ontologies with specific properties • Filling the ontology with instances (not it’s creation) – building the A-box

3. Outline • Approaches to ontological base creation • Method for ontological test base building • Evaluation • Conclusions

4. Manual approaches Automatic approaches Filling the ontology with instances

5. Generic ontology editors • Understand the generic structure of the ontology • Immediately usable • Domain independent • Insufficient validation and user comfort • Suitable for experts (ontology engineers)

6. Generic ontology editors

7. Specialized ontology editors • Freedom in adjusting to a given ontology and user requirements • Sophisticated validation based on the knowledge of the ontology • Development and maintenance costs • Coupled to a ontology • Suitable also for non-experts

8. Specialized ontology editors JOE – Job Offer Editor

9. Wrappers • Parse Web pages and produce structured output • Need well structured pages • Do not need a human involvement • Significant amount of acquired data • Development and maintenance costs

10. Generators • Reusing the already existing data • Increase the size of the ontological base • Instances of desired properties • Development and maintenance costs • Meaningfulness of the data

11. Approaches to Ontological Base Creation • Different approaches have different benefits and disadvantages • They support each other • They can be adjusted • Invested time • Development of tools

12. Method of Ontological Base Creation • Specification of the requirements for the ontology • Amount of data • Range of properties of the instances • Instance detail • Quality • Analysis of the domain and information sources • Generally no approach can separately satisfy the requirements • Adjusting the manual and automatic approaches

13. 1 ) Generic editor 2 ) Specialized editor 4 ) Generators 3 ) Wrappers Method of Ontological Base Creation Web SWEE Ontology

14. Satisfaction of the requirements to ontological data

15. Satisfaction of the requirements to ontological data • Generic editor

16. Satisfaction of the requirements to ontological data • Generic editor • Specialized editor

17. Satisfaction of the requirements to ontological data • Generic editor • Specialized editor • Wrappers

18. Satisfaction of the requirements to ontological data • Generic editor • Specialized editor • Wrappers • Generators

19. Evaluation of the method • NAZOU (nazou.fiit.stuba.sk) • Ontology consists of 740 classes (670 belong to taxonomies) • All approaches used • MAPEKUS (mapekus.fiit.stuba.sk) • Ontology consists of 390 classes (360 belong to taxonomies) • Only one approach used

20. Conclusions • Solution for building ontologies for semantic Web application experimental evaluation • Tunable method based on different approaches of ontology instance creation • Evaluated in the domain of job offers and scientific publication • Developed two SWEE ontologies • Job offer ontology • Publication metadata ontology