Explained: Why Miley Cyrus albums sell

The researchers chose to study adolescents between the ages of 12 and 17, a cohort thought to be highly susceptible to social influence, and known to buy at least one third of albums in the United States. Each participant heard a short clip of a song downloaded from the social-networking website Myspace. Following the clip they were asked to make two ratings, one indicating how familiar they were with the clip (which was always the hook or chorus of the chosen song) and one indicating how much they liked the clip on a five point scale. The clip was then played a second time, and they were again asked to rate how much they liked the song. However, in two thirds of these second trials the teens were shown a popularity rating that was estimated based on the number of times the song was downloaded.

When no information about the popularity of a song was displayed, teens changed their likability rating of the song 12 percent of the time. Not surprisingly, after being shown the popularity of a song, teens changed their ratings more frequently, on average 22 percent of the time. This difference was highly significant, and it is worth noting that among those who changed their likability ratings, 79 percent of the time teens changed their ratings in the direction of the popularity rating — they followed the crowd.