Facebook studied to see how friendships form

Three Harvard sociologists used Facebook to examine whether people become friends because they resemble one another or whether people become more like their friends over time. These scientists’ paper, published in the Proceedings of the National Academy of Sciences examines how we select our friends and the role that friendship plays in transmitting tastes and new ideas.

They found people’s individual tastes influence the formation of friendships much more than a person’s individual, pre-existing tastes spread through his or her friendships.

The four-year study examined the Facebook activity of a cohort of college students. The researchers studied whether tastes in music, movies and books spread among friends over time. They discovered that students who like certain kinds of music and movies are indeed more likely to become friends on Facebook, but the “diffusion” of tastes through friendship ties was extremely rare.

Friends befriended others with whom they shared interests; they did not generally adopt new interests because had developed new friends.

The finding challenges other, recent, highly-publicized research about the importance of peer influence. Kevin Lewis is the project’s first author and a fellow at the Berkman Center for Internet and Society at Harvard. He said:

Given the prior research on social epidemics, we found the nearly complete absence of peer influence effects to be rather striking.

The researchers found tastes in books don’t seem to influence Facebook friendship formation in the same way as tastes in music and movies.

Watching a movie and listening to music are things that can be done with peers, allowing opportunities for social interaction, bonding and meeting new people, but reading typically is a solitary pursuit.

But if a student’s friends liked “indie/alt” music, the student was less likely to adopt the same tastes, presumably because the value of “indie/alt” taste comes precisely from being the only person among one’s friendship group that likes it.

In contrast, though, the researchers also found that students whose friends expressed tastes in “classical/jazz” were significantly more likely to adopt such tastes themselves, so interest in some musical genres diffused among friends. With these few exceptions, though, preferences did not generally appear to be “contagious” among Facebook friends over the duration of college.

Bottom line: A new study, using college students, observed Facebook interactions to examine how we select our friends and the role that friendship plays in transmitting tastes and new ideas.

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