Sociology 712
Seminar on Social Networks
Introduction
Overview
Expectations for the course
Seminar
Homework
Final paper
Go over the Syllabus
Overview of Social Network Analysis
Theory
Methods
Linked by Barabási
History by Freeman
Introduction
What are the expectations for the course?
1) This is a Seminar
•High level of class participation
•Critical evaluations of reading
2) Homework
•Reading -- lots of it. Read smart.
•These are methods exercises, designed to make sure you
know how to do the procedures. Not complicated, and
usually very short.
3) Final Paper
•Goal is to get something interesting published.
•Paper need to use either the ideas or the methods of this
course
•Can be a revision of another paper (MA, course paper, etc.)
•Can be co-authored (up to 3 authors).
Introduction
Class Overview:
Introduction
We live in a connected world:
“To speak of social life is to speak of the association between people –
their associating in work and in play, in love and in war, to trade or to
worship, to help or to hinder. It is in the social relations men establish that
their interests find expression and their desires become realized.”
Peter M. Blau
Exchange and Power in Social Life, 1964
"If we ever get to the point of charting a whole city or a whole nation, we
would have … a picture of a vast solar system of intangible structures,
powerfully influencing conduct, as gravitation does in space. Such an
invisible structure underlies society and has its influence in determining the
conduct of society as a whole."
J.L. Moreno, New York Times, April 13, 1933
These patterns of connection form a social space, that can be seen in multiple
contexts:
Introduction
Source: Linton Freeman “See you in the funny pages” Connections, 23, 2000, 32-42.
Introduction
High Schools as Networks
Introduction
And yet, standard social science analysis methods do not take this space
into account.
“For the last thirty years, empirical social research has been
dominated by the sample survey. But as usually practiced, …, the
survey is a sociological meat grinder, tearing the individual from his
social context and guaranteeing that nobody in the study interacts
with anyone else in it.”
Allen Barton, 1968 (Quoted in Freeman 2004)
Moreover, the complexity of the relational world makes it impossible to
identify social connectivity using only our intuition.
Social Network Analysis (SNA) provides a set of tools to empirically
extend our theoretical intuition of the patterns that compose social
structure.
Introduction
Why do Networks Matter?
Local vision
Introduction
Why do Networks Matter?
Local vision
Introduction
Social network analysis is:
•a set of relational methods for systematically understanding
and identifying connections among actors. SNA
•is motivated by a structural intuition based on ties linking
social actors
•is grounded in systematic empirical data
•draws heavily on graphic imagery
•relies on the use of mathematical and/or computational
models.
•Social Network Analysis embodies a range of theories
relating types of observable social spaces and their relation to
individual and group behavior.
Introduction
What are social relations?
A social relation is anything that links two actors.
Examples include:
Kinship
Co-membership
Friendship
Talking with
Love
Hate
Exchange
Trust
Coauthorship
Fighting
Introduction
What properties relations do we study?
The substantive topics cross all areas of sociology. But we
can identify types of questions that social network
researchers ask:
1) Social network analysts often study relations as systems.
That is, what is of interest is how the pattern of relations
among actors affects individual behavior or system
properties.
Introduction
What properties of relations do we study?
Other system examples include:
Social Cohesion
Relational (as opposed to property) notions of class
Hierarchy and Domination
Inter-group relations
Introduction
What properties of relations do we study?
2) Networks as social contexts
•How does the network environment affect an actor’s
behavior?
•Examples:
Peer influence on delinquency
Corporate interlocks and political participation
International trade and war
Introduction
What properties of relations do we study?
3) Conduits for diffusion
•Relations are like wires or pipes: risks and resources
flow through relations. This can have very wide
implications:
•Diffusion of innovations (fads, rumors, etc.)
•Disease diffusion (STDs)
Introduction
Where does SNA fit in the overall scheme of Social
Science?
Fast growing,
dynamic field.
Interdisciplinary:
Freeman (fig 1.1)
shows that the
Networks are
showing up in many
more substantive
areas each year
Articles with “social network” in title or abstract in Sociological Abstracts.
Borgatti & Foster JoM 2003 29:991-1013
Introduction
How do we analyze networks?*
Three Levels: Ego-Networks, Partial Networks, and Total
(global) networks
Two Questions: Networks as “dependent” or “independent”
variables
*We’ll describe this more formally in the next class
Introduction
Analyzing networks
Ego - Networks
A respondent and the set of
people they have relations with.
Measures:
Similarity
Size
Types of relations
Density
Pattern of ties
Introduction
Analyzing networks
Total (global) - Networks
The connections among all
members of a population.
Measures:
Graph properties
Density
Sub-groups
Positions
Introduction
Scientific Importance of Networks:
Introduction
Scientific Importance of Networks:
•Where do networks matter?
•Where wouldn’t they matter?
•What is a (the?) key feature of network Barabasi identifies?
•Is Barabasi over-stating his point?
Introduction
Scientific History of Networks:
The Development of Social Network Analysis by Linton Freeman
•Prehistory
•Theory: Comte, Spenser, Durkheim, and most
importantly Simmel
•Data: A number of early anthropologists (1800s) and
developmental psychologists (1920s).
•Graphic Imagery: Very early in describing descent
systems & kinship. Hobson (1894) showed overlapping
directors
•Mathematics & Computation: Probabiltiy and formal
algebra on relational data (1870s)
All of these were ‘fits and starts’ that did not lead to
anything systematic
Introduction
Scientific History of Networks:
The Development of Social Network Analysis by Linton Freeman
•Birth I: Sociometry (1930s)
-Jacob Moreno is credited with the first systematic use of SNA-like
techniques, though evidence suggests he was aided strongly by Jennings.
The mathematical/probability treatment came from Lazersfeld (1938).
-The thrust died out. Freeman attributes this largely to Moreno’s
idiosyncratic personality.
•Birth II: First Harvard Thrust
-Grounded in the community structure literature of Warner and Lunt.
-Bank wiring room data
-Southern Women data
-Homans’ work on interaction leading to The Human Group
-William Foote Whyte Street Corner Society
-With one exception, most of this work failed to do the math needed to
make it really SNA. More importantly, it didn’t provide a general frame
for others to work within. The actors also moved apart, making progress
difficult.
Introduction
Scientific History of Networks:
The Development of Social Network Analysis by Linton Freeman
•Dark Ages I: 1940s
-Bavelas, Festinger, Harary, Cartwright, Heider, Katz, all
made strong contributions.
-The work was fundamental, but did not take off to other
substantive areas.
•Dark Ages II: 1950s
-Work in Lund, Sweden, looking at innovation diffusion
-Work in Chicago, including Rapoport’s famous studies,
the work was killed by the Communist scare in the 50s
-Columbia had Merton and Lazarsfeld, who developed
centers doing network research, providing a model but not
a strong start
-Everett M. Rogers (from Iowa, through OSU, to Michigan
State) started his work.
-Radcliff-Brown identified the importance of algebreic
models for any social science (see quote on p.103)
-Freeman, Fararo, Sunshine worked from Northwestern
and Syracuse to make progress.
Introduction
Scientific History of Networks:
The Development of Social Network Analysis by Linton Freeman
•Dark Ages III: 1960s
-Ed Laumann, Peter Blau, James Davis, all started work at this
time.
-“each succeeding contribution introduced a new segment of the
social science community to the structural perspective. But, at the
end of the 1960s, no version of network analysis was yet
universally recognized as providing a general paradigm for social
research. By then, however, the broad community of people
engaged in social research were ready to embrace a structural
paradigm.” (p.120)
Introduction
Scientific History of Networks:
The Development of Social Network Analysis by Linton Freeman
•Harvard Renaissance
- The key idea here is that things took off under Harrison White at Harvard.
Introduction
Scientific History of Networks:
The Development of Social Network Analysis by Linton Freeman
•Power of Organizations
•In the end, Freeman attributes the success of SNA to both technical
changes (UCINET, in particular) and organizational changes, particularly
a series of conferences that culminated in the formation of INSNA and
the Sunbelt Social Network Conference.