About the demo

COPAAL is an unsupervised fact validation approach for RDF knowledge graphs which identifies paths that support a given fact (s,p,o). This approach is based on the insight that the predicate p (e.g., nationality) carries mutual information with a set of other paths (e.g., paths pertaining to birthPlace and country) in the background knowledge graph G. Hence,the presence of certain sets of paths in G that begin in s and end in o can be regarded as evidence which corroborates the veracity of (s,p,o). For example, we would have good reasons to believe that BarackObama is a citizen of the USA given that BarackObama was born in Hawaii and Hawaii is located in the USA (see figure below). For detailed information see the <a href="https://pdfs.semanticscholar.org/061d/c4da92e38f0552c12dc36b2b75fbbc98a5fc.pdf">ISWC publication</a>.