Heise, Arvid; Naumann, Felix
Web Semantics: Science, Services and Agents on the World Wide Web
Governments are increasingly publishing their data to enable organizations and citizens to browse and analyze thedata. However, the heterogeneity of this Open Government Data hinders meaningful search, analysis, and integrationand thus limits the desired transparency.In this article, we present the newly developed data integration operators of the Stratosphere parallel data analysisframework to overcome the heterogeneity. With declaratively specified queries, we demonstrate the integration ofwell-known government data sources and other large open data sets at technical, structural, and semantic levels.Furthermore, we publish the integrated data on theWeb in a form that enables users to discover relationships betweenpersons, government agencies, funds, and companies. The evaluation shows that linking person entities of dierentdata sets results in a good precision of 98.3% and a recall of 95.2%. Moreover, the integration of large data sets scaleswell on up to eight machines.