By Constantino de la Vega
When you press the shuffle button whilst listening to music, no matter the app (Apple Music, Spotify, Tidal), does it really play random songs? The short answer is no, it doesn’t, but this is because if it did it wouldn’t really feel random as same genres and artists could come up next to each other.
The long answer is: humans have a reflex in their brain that leads them to think that if something has not happened for a while, it is likely to happen shortly. This is known as the ‘Gambler’s Fallacy’. Take for example a coin toss; If one tosses the same coin twice and both times you got heads, you expect for the coin to land on tails the next time you toss it. But this would be wrong, as the chances of getting heads are still the same as the chances of getting tails. The same thing happens with music: whenever you feel that a song has not been played for a long time, you feel like it should shortly, but again, this would only be the Gambler’s Fallacy coming into action.
People would often complain that same genres or artists would come up next to each other, thus making the shuffle button a “non-random utility”, and so they changed the button again and again but complaints were still coming in till one day they decided to make something that convinced everyone.
The new algorithm works like this: imagine there are 3 Beatles songs and 4 Rolling Stones songs in the same playlist. The way the possibilities are handed out are as follows: there is a 33.33% of a Beatles song coming up, as there are 3 songs inside that playlist from that band, and a 25% of chances of a Rolling Stones song to come up, as there are 4 rolling stones songs inside the playlist. This, in some ways, is random, but then again, it technically isn’t.
Though the shuffle button isn’t technically a random song player, it is as random as our brains will admit to believe.
The Update 