Affiliations: [a] Vienna University of Economics and Business (WU), Welthandelsplatz 1, 1020 Vienna, Austria. E-mails: firstname.lastname@example.org, email@example.com | [b] Vienna University of Technology (TUW), Inst. of Software Technology, CDL-Flex, Favoritenstrasse 9-11/188, 1040 Vienna, Austria. E-mail: firstname.lastname@example.org | [c] MODUL University Vienna, Am Kahlneberg 1, 1190 Vienna, Austria
Abstract: Crowdsourcing techniques provide effective means for solving a variety of ontology engineering problems. Yet, they are mainly used as external support to ontology engineering, without being closely integrated into the work of ontology engineers. In this paper we investigate how to closely integrate crowdsourcing into ontology engineering practices. Firstly, we show that a set of basic crowdsourcing tasks are used recurrently to solve a range of ontology engineering problems. Secondly, we present the uComp Protégé plugin that facilitates the integration of such typical crowdsourcing tasks into ontology engineering from within the Protégé ontology editor. An evaluation of the plugin in a typical ontology engineering scenario where ontologies are built from automatically learned semantic structures, shows that its use reduces the working times for the ontology engineers 11 times, lowers the overall task costs by 40% to 83% depending on the crowdsourcing settings used and leads to data quality comparable with that of tasks performed by ontology engineers. Evaluations on a large anatomy ontology confirm that crowdsourcing is a scalable and effective method: good quality results (accuracy of 89% and 99%) are obtained while achieving cost reductions of 75% from the ontology engineer costs and providing comparable overall task duration.