Managing and Consuming Completeness Information for Wikidata Using COOL-WD

Wikidata is a fast-growing, crowdsourced, and entity-centric KB that currently stores over 100 million facts about more than 21 million entities. Such a vast amount of data gives rise to the question: How complete is information in Wikidata? It turns out that there is no easy answer since Wikidata currently lacks a means to describe the completeness of its stored information, as in, Which entities are complete for which properties? In this paper, we discuss how to manage and consume meta-information about completeness for Wikidata. Due to the crowdsourced and entitycentric nature of Wikidata, we argue that such meta-information should be simple, yet still provide potential benefits in data consumption. We demonstrate the applicability of our approach via COOL-WD (http: //cool-wd.inf.unibz.it/), a completeness tool for Wikidata, which at the moment collects around 10,000 real completeness statements.