4. Cyclical Pattern of the Rise and Fall of an Online Community Due to a Troll

A deviant behavior against an online community such as a troll sometimes forces a community to close. A troll’s action is regarded as a crime of pleasure: a selfish, anonymous individual feels delight in inflaming others and in seeing their confusion, knowing that there is no effective sanction for such behavior in an online community. The most effective countermove, by popular opinion, is to completely ignore the troll: “Do not feed the troll.” There also exists the unintentional troll, who is unaware that he or she is in fact trolling. If a troll is motivated by evil-minded pleasure and a secure feeling because there are no effective countermoves, it is not surprising that an intentional troll occurs. However, an unintentional troll is also not trivial. To understand a troll thoroughly, we formulated an anti-community strategy and a pro-community strategy, to express a troll’s behavior and a community member’s behavior, respectively, and we also assumed a third strategy: a de-community strategy. We executed evolutionary simulations with the three strategies, and then examined their outcomes. We found that we could replicate the situation where an excessive response against a troll leads to the closure of an online community and that an unintentional troll can have the same result. We also found the cyclical pattern of a dominant strategy such as rock-paper-scissors.