Spotify’s Music Selection
Spotify’s new Discovery mode, Nestify, uses information from your previous Spotify listening habits to recommend new music. It is based on several factors, all relating to the concept of clusters. Spotify developed the system because they realized people don’t keep track of the music they listen too all the time. For example, you may think you listen to a lot of indie music, but in reality you have played music in the pop genre significantly more times and with more consistency.
Spotify uses clusters to find you new songs. If we take your music listening habits for one genre, pop, usually you can see that the music is more diverse, just by the nature of pop music, than other genres, like indie. Because of this, finding new music becomes difficult because the amount of pop music to suggest is so varied. Spotify uses a system that resembles strong triadic closure to recommend music and playlists. If you listen to one artist a lot, they will recommend another song by that artist, or music that has the same feel as that artist. If you only listen to one song by one artist, chances are you just like that song, not so much the artist, so Spotify will recommend a song with a similar feel to that song. The beauty of the system is that because so many people use Spotify, the data on what music is related to what is easy to obtain. If you were to take the data from everyone on Spotify and group artists by the frequency they are played with other artists, very clear clusters appear. Then Spotify can just grab songs that are played frequently with the songs you listen to. They use a system that is similar to strong triadic closure. If you listen to two songs frequently, then Spotify will grab a song that is historically played with those songs. There are different modes of recommendation, and each one has a different level of how far away the new song that is picked is from the other music you listen to. The further applications of this system are almost unlimited.
Link: http://fivethirtyeight.com/features/spotify-knows-me-better-than-i-know-myself/#fn-1