Jo Reed: Welcome to “Quick Study,” the monthly podcast from the National Endowment for the Arts.  This is where we’ll share stats and stories to help us better understand the value of art in everyday life.  I’m co-piloting “Quick Study” with Sunil Iyengar.  He’s the Director of Research & Analysis here at the Arts Endowment.  Hey, Sunil.

Sunil Iyengar: Hey, Jo.

Jo Reed: You know, when you sent me the study you wanted to discuss this month, I did a triple take, and I think it can be summed up best by a headline from The Guardian, which is, “Mathematicians discover music really can be infectious-- like a virus.”  Say what now?  What is the study?
<laughter>

Sunil Iyengar: Yeah.  It was rather surprising.  Last month in the proceedings of the Royal Society in the UK, for mathematical, physical and engineering sciences, that’s the proper title, researchers took statistical models that are used to monitor the transmission of infectious diseases and they applied those models to understand the popularity of music in many different genres.  They sought to know, in their words, quote, “Could the same social processes that facilitate spread of infectious disease in a population also drive song popularity?”  Well, we’ve all heard of earworms or, you know, songs being catchy or even going viral.  Well, this team from McMaster University in Ontario was curious to know if there’s any predictability in the patterns by which popular music is conveyed from person to person and whether those patterns are similar to those that are found epidemiologically, looking at spread of infectious diseases.

Jo Reed: Okay.  So how do they do this research?

Sunil Iyengar: Their data set came from Mix Radio, an online music streaming service, using data from downloads made through Nokia cell phones from Great Britain over a seven-year period.  We’re talking about downloads, not streaming.

Jo Reed: And when was this?

Sunil Iyengar: Twenty fourteen, actually, was the most recent year.

Jo Reed: Okay.  And what do they find?

Sunil Iyengar: Well, when they looked at the sheer amount of downloads over this period they, maybe not surprisingly, found that pop music as a genre led the pack, followed by rock, then dance music, indie or alternative music, then rap or hip-hop, with, and note this for later, electronica very far behind.

Jo Reed: Well, there’s not much of a surprise there.

Sunil Iyengar: Well, but the number of downloads wasn’t their focus.  The study goes on, asks about susceptibility.  Again, that’s a term from epidemiology.  In other words, how many people might be influenced to download a song from learning about it on social media by people talking about the song or other means? 

To answer this question, the researchers backed into a model for simulating the spread of an infection.  They found that the model fit the data surprisingly well.

Jo Reed: And was there a change in genres when they looked at susceptibility?

Sunil Iyengar: Oh, yes, a big one.  They learned that when you apply the model, electronica surges to the top, followed by rock and rap or hip-hop, well ahead of so-called pop music in terms of how rapidly a song of those genres is likely to spread.  The majority of downloads occur within a shorter time period than do pop songs.  Electronica, at least in the UK, gains in popularity faster than other genres, and as the researchers put it, quote, “it burns through susceptible populations more quickly.”

Jo Reed: Okay.  So this does not necessarily mean that more electronica is being downloaded but rather it spreads quicker through the susceptibility of its fans. 

Sunil Iyengar: That’s right.

Jo Reed: Do they have a sense of what accounts for this?

Sunil Iyengar: Well, the researchers speculate that for electronica fans the social network might be tighter than for genres such as pop, as they say, quote, “Electronica fans may be more passionate about their favorite songs and bands than pop bands and therefore talk about and promote their favorite songs more.”  They also note that pop, since it’s a more mainstream genre, spread largely through passive means like radio.  Who knows?  Maybe understanding these and other factors can help us know why certain genres and songs within those genres catch on in a flash, which ones stay with us longest, and whether there just might be outright immunity to certain genres within certain populations, to use their terms.\

Jo Reed: <laughs> What on earth motivated this study?

Sunil Iyengar: <laughs> Well, setting aside the obvious fact that infectious rates and transmissibility have been on everyone’s mind during the past year and a half, the researchers claim that if such patterns were, quote, “successfully applied to song spread, these might be translated into conclusions about an epidemic of song downloads.  For instance,” they say, “it might be possible to estimate the duration of a song’s popularity, how many people in total will download it or how quickly it will become popular in a population.”

Jo Reed: Am I alone in finding that a little sad, a little chilling?

Sunil Iyengar: <laughs>

Jo Reed: I mean, I know music is a business as well as an art, but can’t you see labels looking at this study and producing music via mathematical models?

Sunil Iyengar: Yeah.  Well, as you know-- as we know, the pervasive use of algorithms to recommend customer preferences, whether it’s video streaming services or in e-commerce, and of course, increasingly using artificial intelligence, it’s still kicking up a lot of questions, some of them ethical and others reflecting on the dominance of certain cultural norms and traditions at the expense of others.  So I don’t know about chilling in this case, but definitely worth closer attention and humane understanding.  With downloads and streaming services--

Jo Reed: Oh, amen to that.

Sunil Iyengar: Yeah.  With downloads and streaming services in particular, I think one wants to make sure that artists or musicians are fully compensated and that they aren’t somehow left behind.

Jo Reed: Absolutely.  Well, Sunil, thank you so much.  This was definitely eye-opening.

Sunil Iyengar: <laughs> Hope so.  Thank you, Jo.

Jo Reed: <laughs> I’ll talk to you next month.  That was Sunil Iyengar.  He’s Director of Research & Analysis here at the National Endowment for the Arts.  You’ve been listening to “Quick Study.”  The music is “We Are One,” from Scott Holmes Music.  It’s licensed through Creative Commons.  Until next month, I’m Josephine Reed.  Thanks for listening.