Poster presented at the Large-Scale Sports Analytics Workshop at KDD 2014 (conference on Knowledge Discovery and Datamining) Paper can be found at : http://www.large-scale-sports-analytics.org/Large-Scale-Sports-Analytics/Submissions.html or Research Gate. ---------------------------- ABSTRACT: In this paper, we investigate the feasibility of using collec-tive knowledge for predicting the winner of a soccer game. Specifically, we developed different methods that extract and aggregate the information contained in over 50 million Twitter microposts to predict the outcome of soccer games, considering methods that use the Twitter volume, the sen-timent towards teams and the score predictions made by Twitter users. Apart from collective knowledge-based pre-diction methods, we also implemented traditional statistical methods. Our results show that the combination of different types of methods using both statistical knowledge and large sources of collective knowledge can beat both expert and bookmaker predictions. Indeed, we were for instance able to realize a monetary profit of almost 30% when betting on soccer games of the second half of the English Premier League 2013-2014.