So should we just lock ourselves up in our rooms and stop paying attention to what others are doing? Not exactly (although it is true that we would make better collective decisions if we all stopped taking only our friends advice) Much of the time imitation works. At least in a society like America’s, where things generally work pretty well without much top-down control, taking your cues from everyone else’s behavior is an easy and useful rule of thumb. Instead of having to undertake complicated calculations before every action, we let others guide us. Take a couple of everyday examples from city life. On a cloudy day, if I’m unsure of whether or not to take an umbrella when I leave my apartment, the easiest solution— easier, even, than turning on the Weather Channel—is to pause a moment on the doorstep to see if the people on the street are carrying umbrellas. If most of them are, I do, too, and it’s the rare time when this tactic doesn’t work. Similarly, I live in Brooklyn, and I have a car, which I park on the street. Twice a-week, I have to move the car by 11AM because of street cleaning, and routinely, by 10:45 or so, every car on the street that’s being cleaned has been moved. Occasionally, though, I’ll come out of the house at 10:40 and find that all the cars are stillon the street, and I’ll know that that day street cleaning has been suspended, and I won’t move my car. Now, it’s possible that every other driver on the street has kept close track of the days on which street cleaning will be suspended. But I suspect that most drivers are like me: piggybacking, as it were, on the wisdom of others.
In a sense, imitation is a kind of rational response to our own cognitive limits. Each person can’t know everything. With imitation, people can specialize and the benefits of their investment in uncovering information can be spread widely when others mimic them. Imitation also requires little top-down direction, The relevant information percolates quickly through the system, even in the absence of any central authority. And people’s willingness to imitate is not, of course, unconditional. If I get a couple of tickets because of bad information, I’ll soon make sure I know when I have to move my car. And although I don’t think Milgram and his colleagues ever followed up with the people in their experiment who had stopped to look at the sky, one suspects that the next time they walked by a guy with his head craned upward, they didn’t stop to see what he was looking at. In the long run, imitation has- to be effective for people to keep doing it.
Mimicry is so central to the way we live that economist Her ber Simon speculated that humans were genetically predisposed to be imitation machines. And imitation seems to be a key to the transmission of valuable practices even among nonhumans. The most famous example is that of the macaque monkeys on the island of Koshima in Japan. In the early 1950s, a one-year-old female macaque named Imo somehow hit upon the idea of washing her sweet potatoes in a creek before eating them. Soon it was hard to find a Koshima macaque who wasn’t careful to wash off her sweet potato before eating it. A few years later, Imo introduced another innovation. Researchers on the island occasionally gave the mon key wheat (in addition to sweet potatoes). But the wheat was given to them on the beach, where it quickly became mixed with sand. lmo,though, realized that if you threw a handful of wheat and sand into the ocean, the sand would sink and the wheat would float. Again, within a few years most of her fellow macaques were hurling wheat and sand into the sea and reaping the benefits.
The Imo stories are interesting because they seem to be in stark contrast to the argument of this book. This was one special monkey who hit on the right answer and basically changed macaque “society.” How, then, was the crowd wise?
The wisdom was in the decision to imitate Imo. As I sug geste in the last chapter groups are better at deciding between possible solutions to a problem than they are at coming up with them. Invention may still be an individual enterprise (although, as we’ll see, invention has an inescapably collective dimension), but
selecting among inventions is a collective one. Used well, imitation is a powerful tool for spreading good ideas fast—whether they be in culture, business, sports, or the art of wheat eating. At its best, you can see it as a way of speeding up the evolutionary process— the community can become more fit without the usual need for multiple generations of genetic winnowing. Scientists Robert Boyd and Peter J. Richerson have pioneered the study of the transmission of social norms, trying to understand how groups arrive at collectively beneficial conclusions. They’ve run a series of computerized simulations looking at the behavior of agents who are trying to discover which of two different behaviors is best suited to the environment they’re living in. In the simulation, each agent can try out a behavior for himself and see what happens, but he can also observe the behavior of someone else who’s already made a decision about which behavior is best. Boyd and Richerson found that under these circumstances, everyone benefits when a sizable percentage of the population imitates. But this is only true as long as people are willing to stop imitating and learn for themselves when the benefits of doing so become high enough. In other words, if people just keep following the lead of others regardless of what happens, the well-being of the group suffers. Intelligent imitation can help the group—by making it easier for good ideas to spread quickly—but slavish imitation hurts.
Distinguishing between the two kinds of imitation is, of course, not easy, since few people will admit that they’re mindlessly conforming or herding. But it does seem clear that intelligent imitation depends on a couple of things: first, an initially wide array of options and information; and second, the willingness of at least some people to put their own judgment ahead of the group’s, even when it’s not sensible to do so.
Do such people exist? Actually they’re a lot more common than you’d expect. One reason is that people are, in general, overconfident. They overestimate Their abi1it their level of knowledge, and their decision-making prowess. And people are more overconfident when facing difficult problems than when facing easy ones. This is not good for the overconfident decision makers themselves, since it means that they’re more likely to choose badly. But it is good for society as a who1e because overconfident people are less likely to get sucked into a negative information cascade, and, in the right circumstances, are even able to break cascades. Remember that a cascade is kept going by people valuing public information more highly than their private information. Overconfident people don’t do that. They tend to ignore public information and gO on their gut. When they do so, they disrupt the signal that everyone else is getting. They make the public information seem less certain. And that encourages others to rely on themselves rather than just follow everyone else.
At the same time, even risk-averse people do not, for the most part, slavishly fall in line. For instance, in 1943 the sociologists Bryce Ryan and Neal Gross published a study of the way Iowa farmers adopted a new, more productive hybrid seed corn. In their study, which became the most influential study of innovation in history, Ryan and Gross found that most farmers didn’t investigate the corn independently as soon as they heard about it, even though there was good information available that showed it increased yields by 20 percent. They waited until other farmers had success with it and then followed their example. So that suggests that a cascade was at work. But in fact, even after witnessing the success of their neighbors, the farmers did not seed their entire fields with the hybrid corn. Instead, they set aside a small part of a field and tested the corn for themselves first. Only after they were personally satisfied with it did they start using the corn exclusively. And it took nine years from the time the first farmer planted his field with the new corn to the time half of the farmers in the region were using it, which does not suggest a rash decision-making process.
Similarly, in a fascinating study of how farmers in India decided whether or not to adopt new high-yielding-variety crop strains during the Green Revolution of the late 1960s, Kaivan Munshi shows that rice farmers and wheat farmers made their decisions about new crops in very different ways. In the wheatgrowing regions Munshi looked at, land conditions were relatively uniform, and the performance of a crop did not vary much from farm to farm. So if you were a wheat farmer and you saw that the new seeds substantially improved your neighbor’s crop, then you could be confident that it would improve your crop as well. As a result, wheat farmers paid a great deal of attention to their neighbors, and made decisions based on their performance. In rice-growing regions, on the other hand, land conditions varied considerably, and there were substantial differences in how crops did from farm to farm. So if you were a rice farmer, the fact that your neighbor was doing well (or poorly) with the new crop didn’t tell you much about what would happen on your land. As a result, rice farmers’ decisions were not that influenced by their neighbors. Instead, rice farmers experimented far more with the new crop on their own land before deciding to adopt it. V/hat’s telling, too, is that even the wheat farmers did not use the new strains of wheat until after they could see how the early adopters’ new crops did.
For farmers, choosing the right variety of corn or wheat is the most important decision they can make, so it’s perhaps not surprising that they would make those decisions on their own, rather than simply mimicking those who came before them. And that suggests that certain products or problems are more susceptible to cascades than others. For instance, fashion and style are obviously driven by cascades, which we call fads, because when it comes to fashion, what you like and what everyone else likes are clearly wrapped up with each other. I like to dress a certain way, but it’s hard to imagine that the way I like to dress is disconnected from the kind of impression I want to make, which in turn must have something to do with what other people like. The same might also be said, though less definitively, about cultural products (like TV shows) where part of why we watch the show is to talk about it with our friends, or even restaurants, since no one likes to eat in an empty restaurant. No one buys an iPod because other people have them—the way they might, in fact, go to a movie because other people are going—but many technology companies insist that information cascades (of the good kind, they would say) are crucial to their success, as early adopters spread the word of a new product’s quality to those who come after. The banal but key point I’m trying to make is that the more important the decision, the less likely a cascade is to take hold. And that’s obviously a good thing, since it means that the more important the decision, the more likely it is that the group’s collective verdict will be right.