Do they post or simply respond to posts?
Do they add to the conversation or attempt to Sabotage the conversation?
Are they "more patient" than you would expect? If so...they are PAID trolls...
Does the administrator of the group or page identify themselves as such and their political agenda?....(If not...the page/group was put up BY a Troll)
Researcher's study of fours years of what a troll is...link
4 Pillars Of TrollingNot all trolls are the same, but here are some calling cards, according to Whitney Phillips.
1. Self-ID. Trolls think of themselves as trolls and usually aren't afraid to say it.
2. Vernacular. It's always changing and often grammatically incorrect on purpose and has previously included terms such as "plox" (please), "fap" (masturbation), and "sauce" (asking for the source of an image).
3. Lulz. This pointed laughter is the troll reward, virtual troll food, an acknowledgement and reaction to a troll attack that is more participatory than regular laughter.
4. Anonymity. The center of a troll's power, it's the virtual cloak that lets a sane person acts a little insane online.