Among the algorithms that run our online lives, Pandora's Music Genome Project may not be as critical as Google's search equations, but the math behind the self-programming Web-radio service seems just as opaque, according to BoingBoing.net.
Some of that mystery is by design, but Pandora's been a little more public about how it gathers and grades the more than one million tracks in its collection. And over a long briefing at its Oakland offices and subsequent follow-ups over e-mail, it told me a few more details.
First, humans grade the songs, not computers--and it's surprising how much effort is involved. Pandora's 25 or so music analysts have to assign either one-to-five rankings or more quantitative measures (say, beats per minute) for as many as 450 "genome units" per song.
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