document: Yago : a core of semantic knowledge We present YAGO , a light-weight and extensible ontology with high coverage and quality . YAGO builds on entities and relations and currently contains more than 1 million entities and 5 million facts . This includes the Is-A hierarchy as well as non-taxonomic relations between entities ( such as HASONEPRIZE ) . The facts have been automatically extracted from Wikipedia and unified with WordNet , using a carefully designed combination of rule-based and heuristic methods described in this paper . The resulting knowledge base is a major step beyond WordNet : in quality by adding knowledge about individuals like persons , organizations , products , etc. with their semantic relationships - and in quantity by increasing the number of facts by more than an order of magnitude . Our empirical evaluation of fact correctness shows an accuracy of about 95 % . YAGO is based on a logically clean model , which is decidable , extensible , and compatible with RDFS . Finally , we show how YAGO can be further extended by state-of-the-art information extraction techniques .
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