We talk a lot about the “viral” way in which trends and topics spread around the intermatubez; it’s a useful metaphor because it’s one we have a precedent for. But as with with most things, it’s not quite so simple as all that; Ars Technica reports on research that shows meme transmission can be modelled pretty successfully by the confusing (yet surprisingly ubiquitous) principles of Game Theory:

The popularity growth of things like websites or gadgets is often described as being similar to an epidemic: a network with a lot of connections between people increases exposure and then adoption, as do links stretching between dissimilar groups. When the trend in question spreads to a node with a lot of connections (like a celebrity), its popularity explodes. While this is fitting for some cases, in others it’s an oversimplification—a person’s exposure to a trend doesn’t always guarantee they will adopt it and pass it on.

“It is not only the intrinsic value of a new technology (or other types of innovation) that makes it attractive. It is also the number of friends who have adopted it,” Amin Saberi, one of the authors, told Ars. In instances where there is incentive to make the same decision as people around you, the authors of the paper argue, the spread of innovations may instead follow rules of game theory, which differ in big ways from the rules of viral or epidemic trends.

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The model seems to apply less to individual pieces of content, where simple exposure is enough to create huge growth. On the other hand, it could explain, for instance, loyalty to sites that distribute that content, like Digg and Reddit, or to particular genres of memes. The authors say it also crops up in choices that influence social connections, like the choice between voting Republican or Democratic, or to adoption of technology, like choosing between Verizon and AT&T.

Dr. Saberi gave the following example: “the reason I am using Facebook as opposed to another social network is not just its quality… it is also because I have a lot of friends who are using it”; he notes this could also apply to operating systems. Likewise, while there are many reasons to choose one cell phone carrier or another, features like free calls or texts within a network can influence a group of friends to migrate to the same network as each other.

Far from a complete explanation, then, but still an insight into the complexity of emergent behaviours at societal levels.