Before the rise of online social media, gathering data on opinions was expensive and usually achieved at very small scale. When users on the Web started communicating massively through this channel, social networks became overloaded with opinionated data. In that aspect, social media has opened new possibilities for human interaction. Microblogging platforms, in particular, allow real-time sharing of comments and opinions. Twitter,1 an extremely popular microblogging platform, has millions of users that share millions of personal posts on a daily basis. This rich and enormous volume of user generated data offers endless opportunities for the study of human behavior.