The Psychology of Music Preferences

Apple has just released a version of iTunes with a new feature called Genius. Genius makes custom playlists (of either music you own or music you might want to by) based on a secret algorithm. If you opt-in, iTunes sends all of your listening history data (e.g., track names, artist names, playcounts, skipcounts) to a central server. The algorithm then looks for patterns in worldwide listening trends. To use Genius you right-click a particular song, choose 'start Genius', and BANG you've got a list of 'similar' songs. I'm loving it. It's helped me rediscover some music that Dan had given me but that I hadn't listened to much.

This got me thinking about how one might statistically look for trends in music preferences. I wondered if there'd ever been a factor analysis of music preferences. A factor analysis is a statical technique for finding trends amongst different variables. It's often used in personality research. You ask a large sample of volunteers a whole stack of questions (e.g., "On a scale of 1 to 10 how much do you like parties?", "How much do you like being the center of attention?" etc.) and look for shared variance in the responses. I've written about factor analyses of personality related data before here.

Anyway, a quick literature search turned up this article in the Journal of Personality and Social Psychology:

Rentfrow, P.J., Gosling, S.D. (2003). The Do Re Mi’s of Everyday Life: The Structure and Personality Correlates of Music Preferences. Journal of Personality and Social Psychology, 84(6), 136-1256.

Among the studies reported is a factor analytic study of music preferences. 1,704 students from the University of Texas were asked to rate each of 14 music genres on a scale from 1 ('I don't like it at all') to 7 ('I like it a great deal'). The genres were: alternative, blues, classical, country, electronica/dance, folk, heavy metal, rap/hip-hop, jazz, pop, religious, rock, soul/funk, and sound tracks.

The analysis revealed 4 main dimensions (factors) that captured 59% of the total variance. The names given to these factors and the genres associated with them are as follows:

- Reflective and complex (blues, jazz, classical, and folk)
- Intense and rebellious (rock, alternative, heavy metal)
- Upbeat and Conventional (country, sound track, religious, and pop)
- Energetic and Rhytmic (rap/hip-hop, soul/funk, and electronica/dance)

These dimensions are reasonably independent of each other (1). People who like reflective and complex music are just as likely to enjoy intense and rebellious music as they are to not. What these factors mean is that if someone likes a genre related to a particular dimension (e.g., blues) then they'll probably also like the other genres on that dimension (e.g., jazz). The same goes for disliking a genre.

One limitation of this study is that peoples' understanding of genre terms may vary. I might think that I don't like folk music and yet like many songs that others would categorise as folk. It would be great to see an analysis done on song by song ratings, rather than just genres.

Another analysis, which was really interesting, involved looking for relationships between e musical preferences and differences in personality and cognitive ability. They found all sorts of relationships, although most of them were quite small (.2ish). The largest one (.4ish) was between a preference for Reflective and Complex music and the personality characteristic Openness to Experience. Interestingly, there was a small (.2ish) relationship between verbal IQ and liking of Reflective and Complex, Intense and Rebellious, or Upbeat and Conventional music (2).

Very interesting stuff.

I'd love to see these researchers team up with Apple and analyse the iTunes Genius data.

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(1) Upbeat and Conventional and Energetic and Rythmic correlate .5 if allowed to covary.

(2) And no, I don't think this is evidence that music makes you smarter (can you guess why?).

Mark on Science

Science is a special kind of magic, practiced by people called 'nerds'. No body knows how it works for sure, but it probably has something to do with computer machines.

Be careful, science is dangerous. Nerds get so lazy from all their science making that they only have enough strength to stare into space, talk to the internet, or drive their electric wheelchairs.

Sometimes nerds get angry. If too many nerds are angry at one time, electricity stops working and nuclear bombs go off. Damn you nerds! (but don't tell them i said that)

Luckily, normal people can reap the rewards of science without having to risk their own sanity, because nerds are happy to do science for you. They will accept monetary compensation, but are also happy to work for social approval.

One final note. Logic tells us that all nerds wear glasses, but that not all people who wear glasses are nerds. You may not agree with this opinion, but you'll have a hard time convincing me otherwise, as there are two sides to every fact.

The Google Habit

I have to remind myself to google the small stuff.

It occurred to be a while back that with the Internet being as it is, there's really no reason to ever NOT look stuff up. The time it takes to Google a quick answer is so small that it's more efficient to Google than waste any time wondering.

Even for the silly questions that float through one's head. What is the gestational period of an elephant? What is an 'aptronym'? How old is the universe? You can have a preliminary answer in seconds.
But I have to remind myself to Google. It's a habit I'm trying to cultivate.

Google should launch a TV add campaign. Each add should be only 5 seconds and should just ask a question for you to Google:
"Do lead pencils have lead in them? Google it!"
"How many light years to the nearest star? Google it!"

Won't a reliance on Google lead to cognitive atrophy? I'm not sure that it will. Maybe it will free up the mind to think about the hard questions, the big questions, the questions that apply only to me. Of course, this too is a habit I need to cultivate.

(Cross posted at the Subjects of Interest blog. Go there.)