I have a playlist with 150 hours of music on it and it seems to play the same five or six songs every day, no matter what. I wish I could choose "actually random", I wouldn't mind unexpected clustering.
And yet, when Spotify's shit tier algorithm takes over, it kicks me into a similar 5 to 6 meme set of songs every single time. It's an absolute joke.
I can't tell if it's:
- Certain artists are paying Spotify to favor them in randomization?
- There's some kind of shared random seed across devices that results in picking a tiny subset of songs to randomize from in the first place?
- Other?
I do notice that the effect seems to persist for maybe a week, then I'll never hear those songs again, but now it'll be different songs that keep popping up repeatedly.
There's a related effect when you launch a radio station based on an artist or track. If you launch it multiple times in the same day or week, you get the exact same list of tracks. But maybe a week later the tracks have changed, like the radio has been recalculated based on a different random seed.
If you have 100 songs and listen to 1 song per day (which is 1% of the library), on any given day your odds of hearing the same song as yesterday are 1 in a 100.
If you have 1000 songs and listen to 10 per day (still 1%), the odds of hearing a song that was also played yesterday are a little less than 1 in 10, right?
So what matters is not only what fraction of your library's play time you sample daily, but also how finely subdivided the time is into individual tracks for sampling.
No. It's 10*(1/1000)=1%.
It'll happen a few times a year only.
It's 1%. Any specific song is 0.1%.
Assume that you got 10 unique songs yesterday, which is the case ~96% of the time. Then there are 990 songs you didn't hear yesterday, and for every song you listen to today, there is a 990/1000 chance that it's one of those songs. Hence the chance of only hearing new songs today is (990/1000)^10 = 90.4%.
I remember hearing of a bug where if you played on a remote device, it would transfer the first part of your playlist (10? 100 tracks?), and then shuffle would only choose from among them.
But it's been 5+ years so things may have changed and/or I could be remembering completely wrong.
When I still used Spotify, I would get a dozen of my favorite artists mixed into basically any "playlist" I pick. Was one of the reasons I quit Spotify - they are too opinionated on what I should listen to.
Clustering apparently ought to feel deliberate. Now think back to when you had actual DJs selecting tracks on the radio. One of the techniques was "Two from a particular band." Not two from a band with some tracks between them.
Similarly, one can do a "Four tracks from 1994" to provide a cluster in time, another technique I've heard.
If anything, the more metadata you have, the more you can provide short runs of something. Microgenres, for example.