Category Archives: social norm

The science of friendship

Flickr/JimBoudThere is an interesting article by Robin Dunbar in The New Scientist: Dunbar’s Number was named after Robin, from his theorizing that humans only had the brain capacity to manage roughly 150 relationships, although depending on gender, social skills and personality, this number could vary from 100-250.  Dunbar observes that communication often breaks down when one exceeds 150 individuals (as evidenced in the Crimean War by the Charge of the Light Brigade) and the modern military and businesses only exceed these limits through strict hierarchies.

Dunbar theorizes that language, laughter and communal music-making evolved as a way to stay connected to a larger group of individuals than possible through physical acts like grooming. Dunbar: “[N]ot only can we speak to many people at the same time, we can also exchange information about the state of our networks in a way that other primates cannot. Gossip, I have argued, is a very human form of grooming.”  Christakis and Fowler (in the excellent book Connected) note that “…language is a less yucky and more efficient way to get to know our peers since we can talk to several friends at once but only groom them one at a time.  In fact, in a conversation with a small group, we can assess the behavior, health, aggressiveness, and altruism of several individuals simultaneously.  Plus, we can talk to someone else while engaged in another activity, like foraging for food in a refrigerator.”  Christakis and Fowler note how radical the idea is that language evolved not primarily as a way to exchange information but to maintain group cohesion.   “Dunbar estimates that language would have to be 2.8 times more efficient than grooming in order to sustain the [average] group size seen in humans” (one speaker per 2.8 listeners).

While language may have originally evolved, as per Dunbar, to maintain a slightly larger group size, once developed it was in principle possible to use language to maintain social relations on a tribal or national level.

A few other excerpts from Dunbar’s article:

Group living needn’t tax your intelligence too much. In a loose herd, cues such as body size or aggressiveness may be enough to judge whether you should challenge or steer clear of another individual. In bonded networks, however, you need to know each member’s personal characteristics and those of the friends and relations that might come to their aid. Keeping track of the ever-changing web of social relationships requires considerable mental computing power.

As a reflection of this, there is a correlation between the size of a species’ brain– in particular its neocortex– and the typical size of its social groups. In other words, brain size seems to place a limit on the number of relationships an individual can have. This link between group size and brain size is found in primates and perhaps a handful of other mammals that form bonded societies such as dolphins, dogs, horses and elephants. In all other mammals and birds, unusually large brains are found only in species that live in pair-bonded (monogamous) social groups.

As group size increases so too does the number of relationships that need servicing. Social effort is not spread evenly. Individuals put most effort into their closest relationships to ensure that these friends will help out when they need them. At the same time they maintain the coherence of the group. As a result, social networks resemble a nested hierarchy with two or three best friends linked into larger groupings of more casual friends, and weaker relationships bonding the entire group. This hierarchy typically has a scaling ratio of three– each layer of decreasing intimacy is three times larger than the one before it….

HUMAN SOCIAL NETWORKS

Our social networks can have dramatic effects on our lives. Your chances of becoming obese, giving up smoking, being happy or depressed, or getting divorced are all influenced by how many of your close friends do these things. A good social network could even help you live longer since laughing with friends triggers the release of endorphins, which seem to “tune” the immune system, making you more resilient to disease. So what factors influence the form and function that our social networks take.

In traditional societies, everyone in the community is related to everyone else, either as biological relatives or in-laws. In post-industrial societies this is no longer true– we live among strangers, some of whom become friends. As a result, our social circles really consist of two separate networks– family and friends– with roughly half drawn from each group.

Because the pull of kinship is so strong, we give priority to family, choosing to include them in our networks above unrelated individuals. Indeed, people who come from large extended families actually have fewer friends. One reason we favour kin is that they are much more likely to come to our aid when we need help than unrelated individuals, even if these are very good friends.

Family and friend relationships differ in other important ways, too. One is that friendships are very prone to decay if untended. Failure to see a friend for six months or so leaves us feeling less emotionally attached to them, causing them to drop down through the layers of our network hierarchy. Family relationships, by contrast, are incredibly resilient to neglect. As a result, the family half of our network remains constant throughout most of our lives whereas the friendship component undergoes considerable change over time, with up to 20 per cent turnover every few years.

More than 60 per cent of our social time is devoted to our five closest friends, with decreasing amounts given over to those in the layers beyond, until at the edge of the 150 layer are people we perhaps see once a year or at weddings and funerals. Nevertheless, the outer reaches of our social networks have a positive role to play. The sociologist Mark Granovetter at Stanford University in California has argued that these weak links in our social networks are especially useful in the modern world. It is through this widespread network of contacts that we find out about job vacancies and other economic or social opportunities. More importantly, perhaps, 70 per cent of us meet our romantic partners through these contacts.

Read “Getting Connected” by Robin Dunbar (New Scientist, 4/3/12)

Peer pressure as social cure; Rosenberg’s “Join The Club”

Pulitzer Prize-winning journalist, MacArthur “genius grant” winner and New York Times magazine writer Tina Rosenberg has a new engaging book out called “Join The Club: How Peer Pressure Can Transform the World” about how peer groups and their social ties can be used to cure social problems (“the social cure”).
She chronicles peer groups that spread information and promote positive lifestyles for group members; examples include how Florida fought teen smoking through teen groups taking on tobacco companies through the Truth Campaign; how students effectively protested against Serbian dictator Milosevic by using street theater in a group called Otpor; how LoveLife, a peer group in S. Africa, made AIDS awareness part of an aspirational lifestyle for teens; how the Chicago-based Willow Creek Community Church tries to change lives over small neighborhood-based Table groups; how a village-health worker group in Jamkhed, India is teaching Untouchables to have self-respect; how a peer-based group successfully taught calculus to poor Latino students (“Emerging Scholars“) through nightly study groups; and even how a community drop-in center in Brixton, England for Muslim teens might be effective in anti-terrorism efforts in the UK.
We applaud Ms. Rosenberg on her campaign although much of this “social cure” is old wine in new bottles. Sociologists have known for a long time how social settings can effect our choices for good or ill (see experiments of Asch or Milgram).  And many groups for a long time have thus used the power of peers to increase their effectiveness.
This is after all why many weight loss groups are formed (because the social bonds help people keep weight loss promises) or why Al-Anon uses 12-step group methods to overcome addictions; it is why micro-lending programs (like the Grameen Bank) are organized in groups (to increase repayment rates).
Basically these groups are using social capital.  Social Capital achieves its impact through five main paths: 1) providing increased access to information (like learning of potential project partners or job leads); 2) providing increased sense of meaning that individuals find from social engagement; 3) developing stronger group social norms (e.g., I do something that I might not on my own because I’m worried about my social standing in the group) that members feel pressure to conform to; 4) aiding reciprocity (e.g., I do something for someone else in the group now without expecting any immediate repayment because I expect that they, or someone else will do something for me down the road); and 5) the facilitation of collective action (just jargon for saying it makes it easier to do things that require collaboration and concerted response).  The power that Rosenberg finds in “peer pressure” in these various groups is primarily a function of these paths.
For example, people in a weight loss group stick to their weight loss regimen better because they care about others in the group and what they think and they worry that they will sacrifice these friendships or be embarrassed if they have to admit in the group what caloric foods they snacked on or how they missed their weight loss target.
What is perhaps new or unusual about the book is the acknowledgement of the role of marketing and Rosenberg’s belief that the message has to be positive.
First, marketing can be a powerful reinforcer of group ties and social norms and the desire to be in a group in the first place.  In the South African , although AIDS awareness was a primary goal of LoveLife, they didn’t wear this on their sleeve.  Countless billboards, public service announcements, games and concerts got teens convinced that being part of LoveLife was important.  Teens often exhibit flock tendencies, where the desire of doing something rises as the number of your peers are doing this as well.  LoveLife benefited from this, and AIDS awareness was a less visible but core part of the LoveLife message.  It’s unclear what the relative weights were on the attractive message and marketing, the friendships, and the social norms in what got people to join, stay with and achieve LoveLife goals.
A second one of Rosenberg’s messages is that the approach has to be positive and not based out of fear.  One has to make joining hip and fun rather than like castor oil or broccoli.   We argued something similar in the BetterTogether report.
As Rosenberg notes, “If you want to help someone change their behavior to accomplish a social goal, don’t give them new information and don’t use appeals based on fear. The most effective way is to provide them with a new peer group of people who they can identify with and who can hold them accountable. If you can get people to be active and to overcome their fear, fatalism and passivity, then you’ve gone a long way towards what you want to do.” Rosenberg acknowledges that she didn’t invent the power of groups, but she thinks they could be more widely used and enhanced with these positive lifestyle messages, maybe even for something like tackling global warming.  This approach has its merits, although it should be noted that there are many successful groups like “Mothers Against Drunk Driving” (MADD) that were not about forming a positive lifestyle “Mothers For Sober Drivers” but aligned in their opposition to an evil, so it’s not clear that Rosenberg’s “be positive” message helpfully describes what efforts succeed or fail.

Rosenberg believes there are limits to the “peer pressure” approach. It is time-consuming and she thinks it is less effective at persuasive education about societal facts and trends.

Rosenberg acknowledges that “peer pressure” has gotten its bad image because much of what teens use social pressure to enhance are negative goals: pressure others to buy Ugg boots or silly bandz, or bully an unpopular schoolmate, or pressure other teens to use drugs.  Although she stresses that outside groups (non-profits or government) could use this peer pressure for good, corporations or non-profits could just as well use it for negative ends, something that we openly admit in our writings and Bob (Putnam) has discussed in Bowling Alone.  And social groups might help promote goals about which there is societal disagreement:  teens might be urged to join small religious groups to promote”covenant marriage” (sticking with a marriage even when things get really bad) or to put pressure on teens not to get an abortion, or a corporation might use social networks to sell more products.

My review of “New Tech, New Ties”

Flickr photo by fensterbme

A review that I wrote about New Tech, New Ties: How Mobile Communication is Reshaping Social Cohesion for the American Studies Journal was finally published 3 years after I wrote it!

Rich Ling concludes that unlike cellphone ads would tell you, we can’t be both here and there.  Excerpt:

Cellphones exploded onto the U.S. scene, going from commercial launch in the mid-1980s to 88% penetration by 2008 and penetrating still further in Ling’s Norway. They clearly enable us to be in contact when we previously couldn’t. And they have become a cultural icon: cellphone-shaped balloons, parents hearing kids feigning adult cellphone conversations on their toys—“have your secretary call my secretary.”
Undoubtedly cellphones can challenge social norms. A few examples suffice:

  • A couple walking down street together with each talking to someone else on a cellphone.
  • A plumber summoned to Ling’s Oslo house for a leak strolled into Ling’s home as house guests were saying goodbye. The plumber’s refusal to interrupt his cell call to introduce himself, or ask permission to enter, violated Ling’s sense of social norms, not repaired by the plumber’s nodding to Ling and removing his shoes per the Norwegian custom.
  • Whether we should flush when someone in the adjacent bathroom stall is on an important call.
  • What cellphone conversations should be off-limits in public?

[Read rest of review.]

The Friendship Paradox: using social networks to predict spread of epidemics

Nick Christakis and James Fowler (whose research we’ve previously highlighted) is back with research that shows how one can easily use “sensors” in a network to track and get early warning regarding the spread of epidemics.

They took advantage of the “friendship paradox” to do so.  In any real-life network, our friends are more popular than we are.  [This is true mathematically in any group with some loners and some social butterflies.  If you poll members in the group about their friendships, far more of those friends who are reported are going to be the social butterflies.  If far more people reported friendships with the loners, they wouldn't be loners.  See discussion here.]

Thus by asking random people in a network, in this case Harvard students, about their friends, researchers know that their friends are more centrally located in these networks.    Then one can track behavior among the random group and their friends, in this case the spread of H1N1 flu (swine flu) among 744 Harvard students in 2009.

Those more central in these networks (the “friend” group) got the flu a full 16-47 days earlier than the random group.  Thus, for public authorities, monitoring such a “friend” group could give one early indication of a spreading epidemic; they could serve as “canaries in the coal mine”.  If the process of spreading was person-to-person rather than being exposed to some impersonal information (via a website or a broadcast), one could also track the difference between a random group and a friend group to predict other more positive epidemics, like the spread of information, or the diffusion of a product, or a social norm.

We write in general on this blog about the positive benefits of social ties (social capital), but Fowler and Christakis’ study also shows you that having friends and being centrally located has its costs: in this case getting the flu faster.  [In some ways, this is analogous to Gladwell's discussion in the Tipping Point of how Mavens, Connectors and Salesmen may be disproportionately influential in the spread of ideas through networks, although Fowler and Christakis are far more mathematical in identifying who these central folks are.]

The “friends group manifested the flu roughly two weeks prior to the random group using one method of detection, and a full 46 days prior to the epidemic peak using another method.

‘We think this may have significant implications for public health,’ said Christakis. ‘Public health officials often track epidemics by following random samples of people or monitoring people after they get sick. But that approach only provides a snapshot of what’s currently happening. By simply asking members of the random group to name friends, and then tracking and comparing both groups, we can predict epidemics before they strike the population at large. This would allow an earlier, more vigorous, and more effective response.’

‘If you want a crystal ball for finding out which parts of the country are going to get the flu first, then this may be the most effective method we have now,’ said Fowler. ‘Currently used methods are based on statistics that lag the real world – or, at best, are contemporaneous with it. We show a way you can get ahead of an epidemic of flu, or potentially anything else that spreads in networks.’

Christakis also notes that if you provided a random 30% in a population with immunity to a flu, you don’t protect the greater public, but if you took a random 30% of the population, asked them to name their friends, and then provided immunization to their friends, in a typical network the “friend” immunization strategy would achieve as high immunity protection for the entire network as giving 96% of the population immunity shots, but at less than 1/3 the cost.

The following video shows how the nodes that light up first (markers for getting the flu) are more central and far less likely to be at the periphery of the social network.  The red dots are people getting the flu; the yellow dots are friends of people with the flu and the size of the dot is proportional to how many of their friends have the flu.

Good summary of this research and its implications here: Nick Christakis TED talk (June 2010) – How social networks predict spread of flu.  Nick also discusses some of the implications of computational social science, which we’ve previously discussed here under the heading of digital traces.  Nick discusses how one could use data gathered from these networks (either passively or actively) to do things like predict recessions from patterns of fuel consumption by truckers, to communicate with drivers of a road of impending traffic jams ahead of them (by monitoring from cell phone users on the road ahead of them how rapidly they are changing cell phone towers) to asking those central in a mobile cellphone network (easily mapable today) to text their daily temperature (to monitor for impending flu epidemics).  Obviously these raise issues of privacy, which Nick does not discuss.

News release of study

Academic article in PLoS ONE

James Fowler on The Colbert Report discussing the book by Fowler and Christakis called Connected.


Nick Christakis presenting a talk at TED — The Hidden Influence of Social Networks. (February 2010).  In the talk he notes that while almost half of the variation in our number of friends is genetically-based (46%), that another equally large portion (47%) of whether your friends know each other is a function of whether your friends are the type that introduce (“knit”) their friends together or keep them apart (what they call “transitivity”).  About a third of whether you are in the center of social networks or not is genetically inherited.  Christakis believes that these social networks are critically important to transmitting ideas, and kindness, and information and goodness; and if society realized how valuable these networks were, we’d focus far more of our time, energy and resources into helping these networks to flourish.