Netflix Prize Data: 4 candidate elections with weak preferences

The Netflix Prize was a competition devised by Netflix to improve the accuracy of its recommendation system. To facilitate this Netflix released real ratings about movies from the users (voters) of the system. Any set of movies can be transformed into an election via a process outlined by Mattei, Forshee, and Goldsmith.<br>This data set includes all 4 candidate elections with at least 350 voters generated by this process from 500 randomly chosen movies. Extending beyond prior work by Mattei et al. we allow for weak preferences, i.e., a voter is indifferent between a set of movies if he assigns the same rating to each of them. Thus, there are 75 possibilities to rank a given set of four movies.<br>The archive is gzip compressed and includes 958,857 elections in PrefLib.org's TOC file format (Orders with Ties - Complete List).