Some cities aren't instances of city or big city? Odd behaviour of Wikidata

Solution 1:

These missing statements are not truthy:

SELECT ?statement ?valueLabel ?rank ?best
WHERE {
  wd:Q1733 p:P31 ?statement.
  ?statement ps:P31 ?value .
  ?statement wikibase:rank ?rank .
  OPTIONAL { ?statement a ?best . }
  SERVICE wikibase:label { bd:serviceParam wikibase:language "en". }
}

Try it!

They are normal-rank statements, but there is a preferred-rank statement.

Truthy statements represent statements that have the best non-deprecated rank for given property. Namely, if there is a preferred statement for property P2, then only preferred statements for P2 will be considered truthy. Otherwise, all normal-rank statements for P2 are considered truthy.

Update

I have decreased the rank of the preferred statement just now. Please test your query again.