Ming’s Wisdom

Sometimes pressing “shuffle” on my iPhone or iPod to shuffle my playlist into random order can cause a little confusion.

Are you sure this is random? Maybe the random number generator used in the shuffling software is broken? If it’s truly random, how come it keeps playing the same song from the same singer that I don’t like that much? I feel like when I press “shuffle”, it’s not guaranteed that the order of the songs is random.

Well, I think there’s a reasonable explanation for this. What the computer considers random, is truly random. I’ve thought through how the human mind thinks about this, and what we consider random, goes something like this:

1. When an artist is played, the next song (and the next next song) should not be by that artist again, no matter what.
2. Songs of different genres should be balanced, so that songs of one type shouldn’t bunch up.
3. My favorite songs should be played more often. The more I like it the more often it should play.
4. When a song has played, it shouldn’t come up again later.
5. 6 or more songs in a row sung by artists of the same skin color and/or country is a strong indicator that the playlist is not randomly ordered.

You may have noticed that this is very difficult to achieve, especially considering that #3 and #4 conflict with each other. Perhaps for someone with these criteria for “randomness”, they will never be satisfied that their playlist is indeed random (Maybe #4 should really be “When a song has played, it shouldn’t come up again later… unless I like it.”?). A human perception of a randomized playlist is almost completely a carefully hand-selected mix of their favorite songs. In any case, the shuffle feature could probably use some additions to make it more “random” =).

This entry was posted on Sunday, July 19th, 2009 at 16:33 and is filed under Technology. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.