Tipping Points in Social Networks
by Brad Hunter

     It is midnight on a Wednesday night. I sit, staring complacently at my computer screen, as a pudgy three-dimensional animation of a baby points its finger in the air and wiggles its bottom in a circle. I find myself questioning what mighty coercive power has brought me to this point and I demand to know how it came to possess such power over me. Malcolm Gladwell's book, The Tipping Point, provides me some solace. This is not my fault. My compulsion is merely a product of the networks of which I am a part and their natural tendency to diffuse information, ideas, products, and, of course, dancing babies.

     In the current Age of Information, each of us is embedded in myriad different networks that connect us to the world around us. The most obvious of these networks is the Internet, with sub-networks such as the World Wide Web, the e-mail system, and the instant messaging network. The telephone and fax systems also comprise communication networks of which we are a part. Less obviously, we are connected through our interpersonal relationships to a large social network of friends and acquaintances.

     The immensity, complexity, and variety of our networks certainly provide interesting areas for creative thought and speculation. Can we learn anything about ourselves and the world in which we live by studying these networks? Today's network theorists argue that we can and they spend time studying these networks to try to understand the natural laws that govern their formation and structure. Malcolm Gladwell is one of these network theorists.

Social Epidemics

     Gladwell writes about epidemics, but not the viral sort we might expect. Gladwell's epidemics are social. He believes that many ideas, products, messages, and behaviors we find in society can be characterized by their rapid, exponential spread through our population. Though his book describes epidemics of all kinds of phenomena, he does not precisely define what the phenomena under discourse are. For the sake of clarity, I will call all of the phenomena he describes "messages" through the rest of this paper. These messages and their spread are what he calls social epidemics. Social epidemics have two other characteristics. Firstly, they can be set in motion by seemingly tiny causes. That is, the spread of the epidemics can often be triggered by causes that seem reasonably inconsequential compared to the magnitude of their effects. Secondly, there is a particular moment in time when these epidemics break loose from being contained within a small population and begin to spread. This is what Gladwell calls a tipping point.

Tipping Points

     As the name of the book implies, tipping points are Gladwell's focus. If we accept his premise that social phenomena act as epidemics, then studying when the tipping point in the epidemic occurs seems to be the most illustrative way to understand the epidemic. An interesting analogy for tipping points is chemical phase changes. The transition from water to ice is similar to a tipping point. At thirty-two degrees Fahrenheit, water molecules slow their vibration enough that they begin to form a crystalline structure. These structures begin to meld together until a complete block of ice forms. Above thirty-two degrees, no ice exists. Below thirty-two degrees, water becomes pure ice. Thirty-two degrees is a tipping point for the formation of ice from water.

     Tipping points are derived from ideas in epidemiology, the study of the spread of viruses and other diseases. To understand them better, imagine the example of a simplified flu epidemic, as provided by Gladwell. Assume that the standard flu has a transmission rate of about two percent, meaning that one in fifty people who interact with an ill person in the course of their disease will receive the flu themselves. Now imagine that in New York City, a typical person with the flu interacts with about fifty other people in the course of their disease. This includes people whom they sit next to on the bus, coworkers, family members, and even possibly people on the street. The flu virus is then in equilibrium. Every person with the flu interacts with fifty people and passes it on to one of those people. The rate of the flu within the population remains constant. Now imagine that the Christmas season arrives. More travelers come to New York. People go out shopping more and interact with each other more. More people are clustered into smaller spaces inside in hopes of staying warm. Suddenly, the number of people a typical New Yorker interacts with in the course of the time they have the flu increases to fifty-five. The number of people a single flu victim infects increases to fifty-five divided by fifty, or 1.1. Now for every ten flu victims, an extra person is infected. The rate of flu in the population begins to increase. The number of people infected begins to increase exponentially. So, ten victims infect eleven. Eleven infect 12.1. 12.1 infect 13.3. This continues at an exponential rate. So, we can see how the flu epidemic can begin to increase quickly due to such a simple cause as Christmas shopping and cold weather. The tipping point for this flu epidemic is the beginning of the Christmas season.

The Three Laws

     Gladwell tries to describe when tipping points occur, and thus, how epidemics start. He also tries to show how we can create tipping points ourselves. He proposes three laws of tipping points: The law of the few, the stickiness factor, and the law of context.

The Law of the Few

     The law of the few is a law about the structure of our social network and how messages are passed through word of mouth. It attempts to classify three important types of people who affect the rapid spread of messages through the network. These three types of people are connectors, mavens, and salesmen.

     Connectors are the socialites. They are people with many friends and acquaintances who spend time maintaining these connections. From the network perspective, these are the most central nodes in the social network. Gladwell devised a simple test which allowed him to determine that the number of connections a person has is measured by a power law. This means that connectors are rare in society, but they maintain many more times the number of relationships than the average person does. Because of their ability to spread a message to a huge number of people quickly, connectors are central to understanding how tipping points are reached.

     Mavens are the information gatherers of the social network. They evaluate the messages that come through the network and they pass their evaluations on to others, along with the messages. We can view mavens as regulators of the network because they have the power to control what flows through the network. We trust mavens, and this is especially important because their assessments can often make or break the tipping of an epidemic. Mavens drive many of our social institutions. They are the people who inform the better business bureau, regulate prices, write letters to senators, etc. in order that the rest of us don't have to. Though Gladwell does not argue this explicitly, his description of mavens suggests that mavens can be specialized in areas of expertise and thus many of us may be mavens in our particular areas of interest.

     Salesmen are what the name implies. They are persuaders who are capable of propagating messages through the force of their character. Thus, regardless of the message content or their expertise in the area, they have a certain ability to sell which helps them move messages which may be of importance to them. This ability to persuade strangers to accept a message is why salesmen are important in tipping epidemics.

The Stickiness Factor

     The Stickiness Factor is a law about the actual informational content and packaging of a message. Connections and the personal character of the people trying to spread a message can certainly help it spread, but if the message is not worth spreading, then it is doomed to failure. The stickiness factor says that messages must have a certain character which causes them to remain active in the recipients' minds. Moreover, they must be deemed worthy of being passed on.

     Gladwell admits that the exact characteristics of a message which make it sticky are very difficult to pin down. The stickiness of a message can often only be determined by testing and experimentation. In most of the examples which Gladwell provides, he shows that people often find that their initial belief in the correct packaging for a message is not optimal. The message must be repacked and tweaked several times before tiny changes cause the message to become sticky.

Law of Context

     The law of context is a rule about the environment in which a message spreads. Small changes in the context of a message can determine whether or not it tips. Thus, these social epidemics can fail if the geographic location where they are introduced is wrong or if the current mental state of the population is not prepared for the message.

     Gladwell also points out the importance of small groups for the distribution of messages. He argues that the maximum number of members that can reasonably exist in a human group is one hundred and fifty. He believes that biological limitations in our brain mean that any group larger than this will automatically segment into factions and decrease efficiency. The existence of small groups helps the spread of a message because each member of the group knows every other one and thus the message can easily diffuse through the whole group.

Validity of Argument

     The Tipping Point is not a scientific text with extensive citations, formal definitions and experimental research to justify its position. It relies on rhetoric and examples to provide its justification for the positions espoused within. As such, I don't believe that Gladwell would assert that he has proven that these three rules are the best or only rules which govern epidemics. In fact, the rules are suitably vague and general that one might be tempted to argue that any new rule found which seemed to fall outside of their scope could just be assimilated as information about the few, stickiness, or context.      In fact, we might be tempted to ask whether these laws of the tipping point really provide anything new at all? Gladwell has argued that if we want to spread a message, the audience has to be ready for the message (the context), the message has to be worth spreading (stickiness), and the message must be given to the right people (the few). Phrased this way, the information set forth by Gladwell does not seem terribly edifying. In fact, it just seems like common sense.

     The Tipping Point is undeniably compelling, though, and I definitely gained a feeling of enlightenment from reading it, as if some new tool for understanding the world had been handed to me. What is this new insight into the world? The notion of the tipping point itself and messages as epidemics is probably not terribly earth-shattering. Gladwell argues that "little things can make a big difference" as part of the subtitle of his book. This is certainly true. Tiny causes can create huge effects by propagating the cause throughout the network. However, the epidemic had to reach the tipping point in the first place for that little cause to be so effective. What Gladwell seems to ignore is that there are other factors that prepare an epidemic for its tipping point. Mathematically, the tipping point is the knee of the curve, when a steadily increasing exponential function suddenly crests and begins to increase at the rate we commonly expect from exponential growth.

     Gladwell seems to know this subconsciously, even if he avoids saying it outright. What we are discussing is really the law of context. When Gladwell says that the environment must be right for a message to spread, what he is saying is that there must be a critical mass within the population already, such that it is ready to tip on a slight change. So, unfortunately, I do not believe that this book is an argument that tiny things always spark great change and we should always feel content to focus on the details. However, he does make a case that if an action is going to make a difference, it is very difficult to predict which action it will be and who will perform it. So, every action is equally important as it might be the one which causes the tipping point and without it the tipping point might not occur.

The Importance of Social Networks

     I believe that what Gladwell really provides with this book is a subtle new framework in which to situate our conception of the spread of these messages. Suddenly ideas are packets, streaming and replicating through our social network. Information is a virus copying itself as it travels from us to our friends, family, and acquaintances. When we begin to view our system of social connections as a network and a lifeline with the ability to provide us with important information, messages, ideas and opportunities that we need, the primacy of social interaction becomes more obvious. Stanley Milgram's study which established the notion of six degrees of separation emphasizes this. Other research on small world phenomena has made this notion formal. In networks which are well connected, most other nodes in the network can be reached in only a few steps. If we think about this network, the idea of spreading a message throughout the world does not seem so infeasible. If our message is forwarded on by every one it reaches, it should only take about six or seven iterations of forwarding before it reaches almost everyone in America. Gladwell's rules of the tipping point give us some pointers on what to think about when trying to spread a message, but his true insight is that in spreading a message, we can take advantage of the structure of the networks in which we participate.

     The current world is one of information overload. With so many sources of information and influence vying for our attention, we often shut ourselves off to noisy channels like television or the World Wide Web. We tend to rely on each other to filter information and provide us with the messages that we really need. This, I believe, is why Gladwell focuses most of his practical suggestions for spreading information on finding Mavens. Mavens are trusted by those who know them. Connectors can then transfer the advice of a maven across social boundaries that a maven might not be able to breach.

     This encourages me to strive to be a connector in my daily life. Where before I had believed that maintaining connections and collecting acquaintances was only so much shallow attention-grabbing, I realize now that it is necessary to succeed. We need to know mavens so we can get advice and information. We need to know salesmen to spread our messages. Finally, as we have seen in other books in our course, we need strong social networks for support and health. Maintaining a strong social network of friends with different areas of interest and from different social groups is necessary not only for our personal well-being but for the maintenance of a strong social structure.

     Gladwell's book is not meant to provide step-by-step instructions on how to spread a message. His rules do not exist to be followed directly. Instead his realization is that harnessing the power and characteristics of our social network is how to get ideas to pass through it. His laws of context and stickiness merely provide a caveat that the structure is not the only thing that matters. Many current advertising and persuasive campaigns rely on brute force attempts to reach every member of society through mediums such as television, radio and print. Gladwell shows that these methods may not even be all that effective, and what is truly effective is to convince the persuaders of society and allow them to spread the message. Before that, though, a message-passer must make sure the message is phrased correctly and that the time is right. Gladwell's assertion that messages are most effective when they travel through our complex social network is the insight of the book. Remember that dancing baby from the first page? I wouldn't have rushed online to see that if it had been recommended to me in a television commercial. I looked it up because a friend told me it was funny and that I should. I bet you saw it for the same reason. If a dancing baby can spread throughout America on word of mouth, it's hard to imagine what couldn't.