Am 18.03.2017 um 19:03 schrieb Bob DuCharme:
What makes a predicate a direct claim predicate?
It's a predicate (that's what RDF calls all relationships) that expresses a direct claim (as opposed to a full statement).
Direct claims are one of two ways Wikidata Statements are mapped to RDF. In the wikidata query service, each statement is represented twice - once as a full statement, and once as a direct claim.
Direct claims represent a "naive projection" of wikidata to RDF: everything that is claimed (by anyone) to be true (under any circumstances) is assumed to be true. So you get triples like wd:Q64 wdt:P1376 wd:Q183 meaning "Berlin - capital-of - Germany".
Simple to work with, but incomplete: you also get wd:Q64 wdt:P1376 wd:Q27306 ("Berlin - capital-of - Kingdom of Prussia"), without an easy way to see that one is current and the other is not.
To get all the additional context information, you need to look at the full statement representation, which provides a complex structure of value, qualifiers, and source references. The full mapping will use predicates with the "wds" prefix to connect the item (subject) to the structure representing the statement with all its parts.