Why are popular baby names and other fads always changing?

Imagine you were going to meet two groups of people. You know nothing about their background or age. You only know the names. The first group includes Florence, Mildred, and Ethel. The second group includes Emma, Olivia, and Isabella. Which group would you guess is older?

If you guessed the first group, you would probably be correct: Those names ranked among the most popular baby girl names in the U.S. from 1900 to 1910, while the second set included some of the most popular choices from the 2010s.

Popularity trends cycle over time. From names to clothes to music, it is a good bet that what is trendy today will be unfashionable a decade from now. But why? Although most people can intuitively discern the cool from the outdated, the psychological and social dynamics that drive fads have remained more difficult to understand.

A recent study published in Psychological Review aimed to shed light on those dynamics, using popular baby names as a cultural trend to analyze through mathematical models. The study focused on two opposing — but not mutually exclusive — psychological drivers: our desire to fit in with our peers and our desire to be unique.

Optimal distinctiveness

If we only had the desire to fit in, then we would expect whatever is popular — baby names, a certain cut of jeans, a particular style of music — to stay more or less constantly popular over the decades. On the other hand, if we only wanted to be unique, then we would expect a social world where there is very little consensus on what’s cool: Everyone would be trying to set themselves apart from the pack.

In the real world, groups of people try to strike an optimal balance between these two motives. In other words, most people play a social game where the goal is to find the sweet spot where we broadcast an identity that’s cool but not too eccentric. Something interesting happens when you try to mathematically model this game: Over time, these two opposing motives tend to converge and find equilibrium, where social groups strike a balance that remains mostly static, with no new fads emerging.

But that clearly is not how our social world works (as the evolution from bell-bottom jeans to baggy jeans to skinny jeans shows, for example). So what’s the missing factor? To find out, the authors behind the recent study employed a game theory model that incorporated the uniqueness and conformity motives within different types of social networks.

The researchers found that in very simple social networks, where a handful of neighbors are routinely observing each other and trying to be both similar and slightly different from the other, equilibrium tends to emerge. For example, neighbor A could look at neighbors B and C and make decisions that render his identity similar to his neighbors with an optimal dose of uniqueness. The others could do the same and new trends would not emerge.

But once they scaled up the social networks to represent more complex and realistic communities, the vast majority of the models showed that equilibrium does not occur. A random and perpetual change in fashion is what you would expect, because neighbors cannot observe every single neighbor in this large community that is playing the “game” of striking optimal distinctiveness. Complex social networks leave room for randomness, giving rise to new fads.

One interesting question the study didn’t aim to explore was how these dynamics might play out between distinct social groups. (The models only analyzed what seems to happen within a specific social group, and they assumed that people within these groups were only comparing themselves to other members within the same group.) How, say, people in the punk music scene might change their behavior based on the identity-based decisions of the country club crowd would be a question for a different study.

On a broader note, the study highlights the idea that, like it or not, the social game of striking a balance between uniqueness and conformity is one from which we might not be able to opt out, as Americus Reed II, a marketing professor at the University of Pennsylvania, told Big Think.

“I’ve heard lots of people push back and say, ‘I’m not into brands,’” Reed II said. “I take a very different view. In some senses, they’re not doing anything different than what someone who affiliates with a brand is doing. They have a brand. It’s just an anti-brand brand.”