The Unidan Story: Information Cascades and Reddit
Reddit is a massive social media site with posts about anything and everything. People post stories, information, news, pictures, etc., and then other members of the community can up-vote posts that they liked and down-vote those they did not. In this seemingly democratic way, quality posts get boosted to the top and get more visibility, while lesser quality posts fall out of view.
Enter Unidan, an “excited biologist” who was well known in the Reddit network for answering science questions. His posts routinely did well and he became quite popular. Then, he was banned for cheating the site.
It turns out Unidan was using at least five other accounts to make his primary account more popular. Five up-votes may seem like a pittance compared with the thousands of up-votes the posts on the Reddit front page have daily, but in reality the consequences are massive. Giving a post an early boost like that is a huge deal. Other people who see that the post is off to a strong start are more likely to up-vote it themselves. This is a phenomenon known as an information cascade. Other people thought this post was good, therefore it must be good.
At the same time, Unidan was using his other accounts to down-vote posts that had a chance to be better than his or that conflicted with his point of view. The same phenomenon was occurring- five early down-votes was enough to make the community think it was a bad post, destroying the post through an information cascade.
http://motherboard.vice.com/read/reddits-favorite-scientist-just-got-banned-for-cheating-the-site