Method

Predicate constraints of general-purpose knowledge bases (KBs) like Wikidata, DBpedia and Freebase are often limited to subproperty, domain and range constraints. In this demo we showcase CounQER, a system that illustrates the alignment of counting predicates, like staffSize, and enumerating predicates, like workInstitution-1. Here, users can inspect these alignments through a simple SPO question answering interface.

CounQER is built as a two step approach where we

  1. identify set-valued predicates from a given KB predicates via statistical and embedding-based features, and
  2. link counting predicates and enumerating predicates by a combination of co-occurrence, correlation and textual relatedness metrics.
System overview The figure illustrates the CounQER method.

We analyze the prevalence of count information in four prominent knowledge bases,

  1. Wikidata
  2. DBpedia raw extractions
  3. DBpedia mapped extractions
  4. Freebase

We show that our linking method achieves up to 0.55 F1 score in set predicate identification versus 0.40 F1 score of a random selection, and normalized discounted gains of up to 0.84 at position 1 and 0.75 at position 3 in relevant predicate alignments.


CounQER Output

System output The figure illustrates the output of children of Charlie Chaplin in Wikidata.
System output The figure illustrates the output of faculty size of McGill University in DBpedia.

Related Papers

Uncovering Hidden Semantics of Set Information in Knowledge Bases. Ghosh, Simon Razniewski, Gerhard Weikum. (JWS 2020) [pdf] [code|data]

CounQER: A System for Discovering and Linking Count Information in Knowledge Bases. Ghosh, Simon Razniewski, Gerhard Weikum. (ESWC 2020) [pdf]

Contact

For feedback and clarifications, please contact: Shrestha Ghosh

To know more about our group, please visit https://www.mpi-inf.mpg.de/departments/databases-and-information-systems/research/.