It is important to understand how homophily
changes the way we think

 

Birds
of a feather tend to shop together. 
That we know.  They also tend to talk
together and walk together; and who their friends are affects more than just
what type of jeans they buy.  Their friends
have the capacity to affect their tastes, activities, and their lives overall.  Sociologists call this phenomenon of being
affected by one’s friends “homophily” – the tendency to associate
with people similar to you and the people you associate with tend to act like you
over time (and vice-versa).  

 

Humans
naturally conform to social influence – to their surroundings, environment,
strangers, peers, friends, and the like. 
People tend to socially conform or mimic their friends’ behaviors,
attitudes, etc.  Besides the need for
information, it is understood that people conform so that they will be liked
and accepted by other people. 

 

We tend to
associate ourselves with those who are similar to us in interests, attitudes,
values, background, and personality.  The
old saying that “opposites attract” doesn’t hold much weight; research
evidence by Miller McPherson shows that it is similarity that draws people
together.

 

The Effect Your Friends Have Over
You

 

Your peers are very important.  Judith Rich Harris’s groundbreaking book, The Nurture Assumption, suggests that
peers have a much greater influence on child development than parents or
teachers.  An immigrant 4-year-old boy
from Poland (of China) who just moved to St. Louis is more likely to speak perfect
English and love baseball within a year because he wants to fit in with the
other kids. He might still like
traditional Polish food, but he’ll also quickly love hamburgers and pizza.

 

The social
psychology phenomenon of “mirroring” – people that are your friends
or people that like you in general, tend to physically mimic or mirror your
behavior, vernacular, movements, etc. – is example of the type of subconscious
influence your friends have over you.  As
a social experiment, try incorporating a new word or phrase into your lexicon
and notice how your friends will slowly adopt and use this word or phrase.  Or try crossing your arms during a
conversation with one of your friends and see if they mimic that behavior.

 

On a
gender basis, women are slightly more prone to be influenced by their female
friends than men are by their male friends. 
In her research Sex
Differences in Social Behavior, Alice Eagly hypothesizes that this
stems from the social roles men and women are taught in our society.

 

How Your Friends Affect Your …

– Health

 

Nick
Christakis and James Fowler published a study
last year in the New England Journal of Medicine which suggests that your
friends greatly affect your health.  
According to the study:

 

A person’s chances of becoming obese increased by 57% if he
or she had a friend who became obese in a given interval. Among pairs of adult
siblings, if one sibling became obese, the chance that the other would become
obese increased by 40%. If one spouse became obese, the likelihood that the
other spouse would become obese increased by 37%. These effects were not seen
among neighbors in the immediate geographic location.

 

If your
friend gains weight, it becomes more socially acceptable to gain weight.  And you start to get a different perspective
on what is thin or fat.  And because you
are friends with this individual that gains weight, you may likely partake in
activities with this friend that promotes weight gain, thus increasing your
chances that you too will gain weight.  Of
course, if your friends start to lose weight, it can be a motivating factor to
eat less chocolate cake too.  

 

– Music Preferences

 

 Birds of
feather even sing together.  Noah Mark,
Assistant Professor at UNC Charlotte, wrote a paper in 1998 that suggests that
our music preferences are highly influenced by who we hang out with.  This makes complete sense.  We are limited in our time and capacity to
try everything.  So we tend to try out
and learn about things that our friends are doing, acting as a filter to all
the noise that permeates our ear drums.  I suspect this is also true with the type of sports
you play, art you like, food you appreciate, etc. – all your habits, likes, and
dislikes are massively influenced by your friends’ habits.  

 

– Mood

 

And not
surprisingly, much of your mood and overall disposition can be heavily
influenced by your friends and the type of people around you.  Happy friends will make you happier.  Sad friends will make you more
depressed.  Even thoughts of suicide can
be contagious.  Essentially, mood is
virus that is highly contagious.  Likewise,
when someone out of the blue smiles at you, you usually can’t help but smile
back.  Humans are susceptible of being
influenced and we’re reciprocal beings at the core.  

 

– Political Stance

 

Political
leanings is very closely linked to homophily. 
If you live in an area with more than 65% party registration, you’re
probably getting massively influenced by your neighbors. 

 

 

Using the Understanding of
Homophily for Good Use

 

Homophily can
be actively used to positively impact your life.  Christakis
and Fowler did another study where they found quitting smoking is contagious
and targeted interventions are most successful when done within a group.  It’s analogous to going for a run with a
friend and pushing yourself harder and longer than if you were to just run by
yourself.  Having many people around you
can reinforce positive things like community service or negative things like
UFO cults.  

 

If you are
always trying to hack your life, the best thing you can do is systematically
eliminate unhappy people from your encounters. 
Even a reduction of 10% unhappy people will likely have dramatic affects
on your mood and disposition.  Good-bye
complainers, hello smilers.

 

The best
way to deal with homophily is to understand how you are impacted by it and to hack
your life and make adjustments accordingly. 
To inoculate yourself politically, for instance, start considering the
“other side” of the political isle. 
If you are in San Francisco
(84% Democratic), you might want to read the Wall Street Journal editorials
every day.  Similarly, if you are in the
back countries of Alabama (70% Republican) you should read the editorials of the New York Times every
day.  Don’t let yourself be blindly led
by those you know.  

 

So the
next time you go shopping, be sure to bring along that frugal friend of yours
to help curtail your spending spree – which is definitely not recommended in
this economy.

 

 

(special thanks to Vivek Sodera for
his edits and research)