Extension:Wikibase Quality Extensions

We are currently working on two different approaches to improve the data quality on Wikidata.
 * Data validation using external databases
 * Detecting items that contain statements about external database identifiers,
 * Cross-checking other data within these items with the respective third-party databases,
 * Thus securing the correctness of the data in those items,
 * Where appropriate suggesting different values if the validation failed, and finally
 * Adding the external database as a reference.
 * Using constraints more effectively
 * Allowing for more complex constraints (as statements on properties),
 * Showing an editor of a claim which constraints exist on a given property,
 * Highlighting constraint violations directly where they occur (on a statement or property), and
 * Making it possible to put deliberate violations on a whitelist,
 * Thus making it easier to see which data should be revised and lowering the total number of violations.