5. The one or more computer-readable media of claim 4 wherein a given annotation area of the one or more annotation areas includes overlapping annotations from the extraction results of two or more of the multiple NER services.
4. The one or more computer-readable media of claim 1 wherein the method further includes: identifying one or more annotation areas in a document of the document corpus, each of the one or more annotation areas including one or more annotations in the extraction results for at least some of the multiple NER services.