1. A method of applying role based association to entities in textual documents, the method comprising: obtaining a plurality of textual documents describing a plurality of entities; identifying a relationship between entities and verbs, at least on a sentence level, based on a semantic analysis of the verbs; determining at least one of: a topic, and a sentiment associated to the verbs identified in said textual documents or to sentences associated with said verbs; and using the identified relationship between entities and verbs and a respective determined topic or sentiment associated with the verbs, to determine for each of the plurality of entities: a sentiment level associated thereto, and a level of activity at the at least one topic associated thereto.