Tag Archives: Strength of Weak Ties

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)

Why weak ties are strong for job searches

Flickr photo by pvickering

Mark Granovetter is famous for uncovering the strength of weak ties in job searches (i.e., that weaker ties ironically are more helpful in landing jobs than one’s close friends).  Granoveter, after interviewing job seekers, posited that it was because one’s close friends tie one back to jobs and job leads that one already knew about whereas weak ties connected one to jobs that one hadn’t heard of.

Sandra Smith, sociology at Berkeley, is doing interesting work uncovering the why.  She’s interviewed 157 workers of various races and various job levels at a public university (Berkeley?) to learn of cases where they did and didn’t help people land jobs and what was good or bad about the experience.  Smith notes that in Granovetter’s work the job seekers often don’t know exactly what or was not done by their strong or weak tie.  [Her past work has been on how distrust hurts low-income blacks in the job referral process, but this new work, as of yet unpublished, is more general.]

It turns out, that people generally don’t refer their close friends to jobs for two reasons: 1) they are more worried that it will reflect badly on them if it doesn’t work out; and 2) they are more likely to know of the warts and foibles of their close friends and believe these could interfere with being a good worker (e.g., Jim stays up late to watch sports, or Charles has too much of an attitude, or Jane is too involved with her sick father).  Weak friends one can more easily project good attributes onto and believe this will work out.

She spoke of one interesting case, “Redmond”, who worked in a growing university department that was hiring 30 new people and whose manager asked workers to help refer good employees.  Redmond was asked soon thereafter by the parking attendant at his church whether he knew of any jobs for his wife who had lost her job (both the parking attendant and his wife were Ethiopian immigrants in the US and lived at Redmond’s church).  Redmond barely knew either of them, but took many steps to advance her candidacy (driving her to the interview, introducing her to people at the office, checking on her candidacy, and getting information filled out again when the paperwork was lost, etc.).  Redmond also had 10-15 good friends who needed a job, but he only told 2 about the available jobs, and even for those 2, didn’t take any steps to advance their candidacy since he had reservations about them.

In some cases, people did intervene on behalf of family or friends, but sometimes this was more lukewarm (e.g., enabling their applicant-friend to put the job-holder’s name on the applicant as a referrer, but making no efforts behind the scenes to advance their candidacy).

The job holders seem to put the interests of the workplace generally ahead of the interests of their friends, perhaps because they are jealously guarding their workplace reputation would could be sullied by a poor referral.    The job holders act as “moral” gatekeepers, trying to keep out the unworthy.

Smith is working to try to categorize types of job assistance and what leads one to help a friend/relative vs. helping a weak tie, and whether this assistance is to help the friend or improve the workplace.

Best friends may provide the most new and valuable info

Flickr photo of BFF from nokapixel

Mark Granovetter in a famous 1973 article “The Strength of Weak Ties” observed that it is our weaker social ties that are most likely to provide us access to information we don’t already know about: job leads, cross-fertilizing information that we can use to great advantage in our jobs, new opportunities, etc.

A recent paper by Sinan Aral and Marshall Van Alstyne says that Granovetter neglected to include frequency of contact.  Yes, our weak ties are more likely per contact to provide us new information, but we contact our strong ties so much more often that a majority of novel information actually comes through those strong and demographically similar friends.

Aral and Van Alstyne analyzed nearly a year of e-mail from an executive recruiting firm (heavily dependent on e-mail for communication and where novel information was critical in finding the right candidates) and found that those with a tighter group of friends (which they define via less network diversity) actually got a higher ratio of new information per unit of time and produced higher revenue for the firm.  As the authors hypothesized, recruiters with more diverse networks suffered a big drop in the volume of communication (what they call “channel bandwidth”).  “Interestingly however, reductions in channel bandwidth associated with greater network diversity do not seem to be driven solely by time and effort costs of network maintenance, but also by the nature of the relationships in sparse networks.” Van Alstyne concludes:  “a smaller number of high-bandwidth relationships can be good for you.”

So no need to jettison your best friends for now…

Read “Buddy System” (WIRED May 2011, by Clive Thompson)

See Sinan Aral and Marshall Van Alstyne, “Networks, Information & Brokerage: The Diversity-Bandwidth Tradeoff” (2010)