Hi Ellery and Gerard,
Interesting thread!
I don't know if this could be of interest for you guys, but I have a recent paper where we explore a very simple approach to fact-checking of a knowledge base. We compute the shortest path between entities and convert the distance into a semantic proximity. It's very rudimentary (for one, it doesn't take into account different relations), but it seems to work well on core topics (like geography, US presidents, movies, etc), and it even gives a signal when you ask about stuff that is not contained in the knowledge network itself:
In the paper we use data from DBpedia dumps, but adapting to Wikidata would be straightforward. There is a lot of research on this problem, and it goes under several, related names (link prediction, relation extraction, knowledge base construction, etc). A recent overview of the literature can be found here:
the review is, authored, among others, by some of the people working on Google's Knowledge Vault.
Cheers,
Giovanni