EntityMentions can be linked to multiple entities using a LinkedEntity message lets us add other fields, e.g. confidence.

Attributes

• entityId (type: String.t, default: nil) - entity_id is a concept unique identifier. These are prefixed by a string that identifies the entity coding system, followed by the unique identifier within that system. For example, "UMLS/C0000970". This also supports ad hoc entities, which are formed by normalizing entity mention content.