Mixtape Application: Last.fm Data Characterization
  This report analyses data collected from Last.fm and used to create a real-time recommendation system. We collected over 2M songs and 1M tags and 372K user's listening habits. We characterize users' profiles: age, playcount, friends, gender and country. We characterized song, artist and tag popularity, genres of songs. Additionally we evaluated the co-occurrence of songs in users' histories, which can be used to compute similarity between songs. 
Luciana Fujii Pontello, Pedro H. F. Holanda, Bruno Guilherme, Joao   Paulo V. Cardoso, Olga Goussevskaia, Ana Paula Couto Silva
cs.SI