An important point to mention is that when collecting the data, we consider only the public ones since the private accounts cannot be retrieved or seen publicly. It has been stated that ”The users’ privacy issues were handled as follows. Most ’tweets; on twitter are set public, and can be viewed by any person regardless of membership to twitter. The tweets which require ’following’ the author in order to be accessible are termed private, and they are not reflected on the public data stream (called the public timeline)” [7]