How does Pandora's rating system work?
teej: Each song is classified according to the Music Genome Project (http://en.wikipedia.org/wiki/Music_Genome_Project).  The song's genes are rated according to how strongly they are expressed on a 1-5 scale.  They break down your song ratings into ratings of certain genes and groups of genes (focus traits) and pick a new song that rates highly in the genes you "like".They also account for lemons on a band-level and song-level basis.  If you negatively rate a song, they won't play it again on that station.  If you negatively rate a band twice, they won't play that band again on that station.