Friendship Reciprocity & behavioral change

 
 Image taken from Lord of The Rings (The Fellowship of The Ring)

Image taken from Lord of The Rings (The Fellowship of The Ring)

As a fan of all things Tolkien, I thought it would be appropriate to begin the description of this project with one of my favorite quotes from the realms of Middle Earth.

I don’t know half of you half as well as I should like; and I like less than half of you half as well as you deserve.
— Bilbo Baggins, The Fellowship of the Ring, A Long-expected Party

The hobbits at Bilbo's farewell party found this unexpected statement rather difficult. As Tolkien explains, there was some scattered clapping, but most of the assembled party-goers were trying to work it out and see if it came to a compliment. The difficulty of understanding the statement stems from the linguistic style and language Bilbo used in his speech. But why were those who did understand it disappointed?

I guess for hobbits, just like us, reciprocity is one of the expectations of affectionate relationships. For instance, we assume that when we consider another person a “friend,” that person also thinks of us as a friend. I mean, we like them, they must like us, right? 

When we analyzed self-reported relationship surveys from several experiments around the world (from human subjects, not hobbits!), we found that while most people assume friendships to be two-way, only about half of friendships are indeed reciprocal. In itself this may seem like an interesting but minor finding, but this large proportion of asymmetric friendships translates to a major effect on the ability of individuals to persuade others to cooperate or change their behavior.

For example, when we examined the properties of friendship networks and how the directionality of ties can impact the level of influence that individuals exert on one another (based on analysis of a fitness and physical activity intervention where information about physical activity was collected passively by smartphones), we found that the program was more effective when a unilateral friendship tie existed from the buddy (the person applying peer pressure) to the subject (the person receiving the pressure) than when the friendship tie was from the subject to the buddy. In this example, reciprocal friendships are best, but having a buddy who thinks of the subject as a friend is the next best relationship. We attribute the difference to our peer-to-peer incentive mechanism - as buddies were rewarded based on the progress of the subject, there are likely to be differences in communication when the buddy believes the subject to be their friend versus when they do not.

 
  Change in physical activity under experiment conditions shows that the type of friendship is relevant to the e  ff  ectiveness of the induced peer pressure. The plot shows the mean e  ff  ect size of the covariates (solid circles) and the 95 % confidence intervals (bars) 

Change in physical activity under experiment conditions shows that the type of friendship is relevant to the effectiveness of the induced peer pressure. The plot shows the mean effect size of the covariates (solid circles) and the 95 % confidence intervals (bars) 

 

The findings of this work have significant consequences for designing interventions that seek to harness social influence: 

  1. Intervention designers, whether with fitness programs, smoking cessation programs, or any other attempt to change a subject’s behavior, can't rely on how the subject perceives the relationship with the buddy to create effectiveness.
  2.  Also, we shouldn’t assume people with a high number of social ties are “influencers.” Such people are no better and often are worse than average people at exerting social influence. Our results suggest that this is because many of those ties either are not reciprocal or go in the wrong direction, and therefore won’t lead to effective persuasion.
  3. We demonstrate that an assumption common in previous studies of social influence, namely that friendships are created equal or reciprocal by default, is erroneous, which may have significantly biased the research results. 

Yet, important questions remain puzzling. For instance, how and why this misperception happen? Why are we unable to accurately infer what others think of us. This is particularly surprising given that we are equipped with unique cognitive abilities that allow us to reason about others' minds and interpreting others’ intentions, goals, and beliefs.  One possibility is that the the non-reciprocating side of a dyad can benefit from concealing their relationship status. By disguising the strength of their friendship publicly, one can leverage social advantages from that information asymmetry.  In a sense, it is more advantageous to have people think you like them than know you don’t in many cases.

We hope that by understanding the factors and network properties that impact the level of social influence individuals exert on one another, we can be more effective at promoting behavioral change, disseminating new ideas, and even promoting products.

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