Discussion Question 2
robinlin
Lecture_5.pdf
POLI 100F Lecture 5: Social
Networks and Social Life
Gregoire Phillips
11/03/2020
Overview
1. Announcements
2. Social Networks and Social Life
3. Social Networks and Evolution (a frontier of
research)
Announcements
1. Discussion Questions #1 grades are posted
2. Annotated Bibliography assignment has been
posted
3. Annotated bibliography is 10% of your grade,
and is due Friday by 11:59 PM
4. Discussion Questions #2 will be assigned next
week
5. I will create a short participation quiz for
Wednesday’s lecture due by next Wednesday
The Evolution of Love Anthropologist Helen Fisher broke down love into three
categories for evolutionary purposes:
Photo by Dianna MulletPhoto by Crawford Wilson IIIPhoto by Valeria C Preisler
• Lust: drives reproduction
• Love: affection and resources shared with 1 partner
• Attachment: parental care for young
Finding the One (or Ones) Most future partners are 2-3 degrees removed from one another
The National Survey of Health and
Social Life or “Chicago Sex Survey” (1992) reveals:
• 68% of people were introduced to
their spouse by a common
acquaintance
• 32% met via “self-introduction”
• 53% of one-night-stands were
introduced by someone else
Photo by Wonderlane
Finding the One (or Ones)
60% - school, work, private party, church, social club
10% - bar, personal ad, vacation spot
3% - from the neighborhood
Finding the One (or Ones) If there are one million compatible people for you in the world
that’s 1 in 6,000 people who could be your potential “Mr. Right”…..Sound daunting?
The dispiritingly unromantic conclusion is that you will never
find your one true soul mate…
That’s were social networks come in
Photo by Dieter Drescher
Help I Need Somebody! If you are single and know 20 people, and each of those 20
know 20 others, and each of those 20 know 20 more, then……
20 x 20 x 20 = 8,000 social contacts (for a total of 8,420 within 3
degrees). One of those is probably your future spouse.
Finding the One (or Ones) Friends and family are efficient matchmakers because they can
judge the compatibility of the two parties
Photo by Mike Ortiz
Photo by Tripu, Flikr
Perfect for One Another
Homogamy: tendency of like to marry like race, culture, ethnic
background, political affinities
• 72% of marriages exhibit racial homogamy (2012)
Once married, spouses may become even more similar due to
influence
Photo by Alfred Liu
Photo by Bradley P Johnson
Photo by Johey24, Flikr
Online Dating
Online Dating by 2010
Big Fish, Little Pond
People often care more about their relative standing in the
world than their absolute standing
Why? People are envious…
Photo by TomSaint11Photo by Keven Law
Big Fish, Little Pond In an experiment dealing with attractiveness, participants were
asked which state was more desirable:
A: Your physical attractiveness is 6; others average 4.
B: Your physical attractiveness is 8; others average 10.
• 75% of people preferred A
• 93% of Harvard Grads preferred A
Relative Standing is key to Sex Appeal
Photos by Steve Garfield, Cyril Attias & Fiona Bird, Flikr
Big Fish, Little Pond In an experiment testing the relative standing phenomenon in
the workplace:
• The majority of people involved said they would rather earn a
$33,000 salary with everyone else getting $30,000 than earn
$35,000 and have fellow colleagues earn $38,000
Photo by Seer Snively
Everyone Else is Doing It Social Networks affect our relationships by:
• Influencing perceptions and opinions
• Dictating our position in the network and relative standing
Example: “Indirect Mate Choice”: the tendency to choose a partner based on what others value
Photo by Pedro Simoes
Marry Me? Marriage is said to produce health benefits because married
people exhibit:
• Lower risk of physical disease (heart disease, diabetes, etc.)
• Lower risk of psychological disease (depression, anxiety,
etc.)
Counter arguments:
• unhealthy people are less likely to get married and healthier
are more likely (also homogamy – the fit marry the fit)
• “joint unfavorable environment”: both wife and husband were exposed to something that made them more likely to die
• So? Which comes first, better health or marriage?
Marry Me? #1: Design a novel experiment
• Survey individuals who are married and
individuals who are unmarried in time series
• Create control group of unmarried individuals
that are, on average, similar to group of
married people sampled on important
attributes
• Create treatment group of married individuals
who match control group, but are married
(marriage as treatment)
• Compare two groups
Marry Me? #1: Repurpose existing experiment
• Survey individuals who are married in a time
series
• Identify trend differences in period of time in
which individuals are married or widowed
• Compare times in series to times before or
after
• Quantify effect on variables of interest, and
calculate with relevant statistical qualifications
(lack of true control group, so this is more
questionable)
Grooms Gain More When men get married there is a sharp and dramatic decline in
their risk of death (women do not experience as much of an
immediate benefit)
Time
R is
k o
f d
e a
th
Gets
married
Becomes
widowed
Men
Women
Grooms Gain More
Why?
• Emotional support which has
biological and psychological
benefits (lower heart rate,
improved immune function, etc.)
• Economies of Scale (combined
income=more money)
Photo by Ed Yourdon
Being married adds 7 years to a man’s life and 2 to a woman’s
Grooms Gain More Proposed changes in Men:
• Elimination of “stupid bachelor tricks”
• Receive support and connection to
broader social networks via their wives
Photo by Fabio Lone Photo by David Clow
Photo by Kevin Lim
Dying of a Broken Heart The Widowhood Effect:
• After a wife dies, a husband has a 30%-100% higher mortality
rate in the first year of widowhood
• Risk of heart attack rises after death of spouse
Divorce and Networks
Divorce and Networks
Divorce and Networks
Divorce and Networks
Divorce and Networks
National Longitudinal Study of Adolescent Health
• Complete social network for 90,114 Adolescents at 142 Schools
• Nationally representative
• Wave I (1994-1995), Wave II (1996), Wave III (2001-2002), Wave IV (2007-2008)
Sex, Orientation, and Networks
Sex, Orientation, and Networks
It’s In Our Nature
Photo by cbs.com
Social Networks have recently become more visible with the creation of so many online social
networks, but they have always existed and affected the way people live and interact!
You can watch social networks form on reality TV shows like Survivor.
How Social Networks Form
Photos by Justin S. Campbell and Vlastula, Flickr
The structure of a social network matches the needs of its community.
While an offensive football team might form
an… • aggressive • competitive • changing social network structure
A burning house would hopefully bring about
a… • cooperative • supportive • stable social network structure
Cooperation
Photo by Dave Traynor, * Photos by Chris M *and Inkyhack, Flickr
Cooperation and altruism are not evolutionarily practical.
Survival of the fittest, not the most helpful.
Evolutionary models of cooperation include for 4 types of people:
•Loners •Cooperators •Free-Riders •Punishers
Period 1
Eleni
Lucas Lucas
Lysander
Erika Erika
Harla
Erika
James
Jay
Brecken
Period 2 Period 3 Period 4
Lucas
Erika
Jay
Effects Persist Over Time
Behavior Spreads 3 Degrees
of Separation
1
2
3
The Network Acts Like a Matching Grant
Each a Person Gives in First Round....
Causes Others to Give
1. You are given $10 to split with another person. 2. If he or she accepts your split, you each get your part. 3. If he or she rejects your offer, you both get nothing.
Theoretically, you should accept any split
(something is better than nothing!).
But most offers under $2 are rejected.
The Ultimatatum Game
Photo by YoavShapira, Flickr
The Ultimatum Game
Photo by wwarby, Flickr
The Ultimatum game only matches economic predictions (that
player 1 takes as much as possible and player 2 accepts anything)
within fairly isolated cultures.
The Dictator Game
Photo by UnorthodoxY, Flickr
A new game was created:
The Dictator Game
The Rules:
1. You have $10. 2. You make an offer to split it however you want with another person. 3. They MUST accept. 4. You both get to keep the money.
In this game, you would expect player 1 to keep all
$10, but most of the time she gave player 2 some!
Homo economicus
Photo by kansasexplorer 3128, Flickr
This tongue-in-cheek term means “Economic Man.” It characterizes humans as selfish and rational.
If people where really like this, they would not share!
Homo dictyous (literally “network man”) better describes how people really are.
• Three Degrees – Obesity
– Smoking
– Drinking
– Happiness
– Loneliness
– Depression
– Cooperation
– Word-of-mouth referrals
– Inventor ideas
Networks Are in Our Genes
Photos by peter.ca, Flickr
Genes affect our emotions.
If you are predisposed by your genes to feel lonely, you might
become disconnected from your network.
Networks Are in Our Genes
Photos by EUSKALANATO, Flickr
The ability to understand and work within social networks is even
programmed into our anatomy
The complexity of social networks could account for the large
size of the human brain.
Networks Are in Our Genes
Human brains are larger than monkey brains and human groups
are larger than monkey groups.
Monkeys groom each other one at a time, but humans can talk
To four people at once.
It seems the size of the brain
limits the size of the group.
Most natural human groups
are capped at about 150
People (Dunbar’s number).
Photos by thsutton, Flickr
Dunbar’s Number
•Homo Sapiens
(150)
Big Picture
Behaviors Obesity Smoking
Happiness Loneliness
Cooperation
Social Networks
Big Picture
Genes Dopamine Serotonin
Behaviors Obesity Smoking
Happiness Loneliness
Cooperation
?
Big Picture
Genes Dopamine Serotonin
Behaviors Obesity Smoking
Happiness Loneliness
Cooperation
Social Networks
D R
D 2
(h o m
o p h il y )
C Y
P 2 A
6
(h e te
ro p h il y ) Add Health
FHS Replication
Change in Friend's Genotype Associated
With Each Additional Subject Allele
-0.1 0.0 0.1 0.2
p=0.02
p=0.0001
p=0.006
p=0.008
