You’ll do better dealing with bad coordinates if your system can recognize how bad particular cases are.

 

     The worst error I see in Wikipedia is that sometimes people get east and west confused,  so there is this mirror image of Europe reflected across the U.K.  You find cute little Czech towns out in the Atlantic with the seamounts and the shipwrecks.

 

     If you computed the bounding circle for the points,  the radius would be an indicator of the degree of confusion that would be highly effective for smoking out the craziest “rouge points”

 

    There are other cases where reasonable parties could disagree about the exact coordinates for things and it is not worth sweating it.  Where exactly is the state of Ohio or Lake Superior?  These things are shapes,  not points.  You couldn’t argue about an uncertainty radius of 10 kilometers for a point like that,  in fact,  the consumer system should know that it can move those labels around a little bit to improve other layout metrics.