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The (network) Structure of Sociology Production
James Moody
Ohio State University
American Sociological Association
Philadelphia, August 2005
Introduction
"Science, carved up into a host of detailed studies that have no
link with one another, no longer forms a solid whole."
Durkheim, 1933
Stratification
Social
Welfare
Organizations
Historical
Sociology
Crime
Gender
Health
Introduction
The extent to which science is “carved up into a host of
detailed studies that have no link with one another” is a
question of network cohesion.
•A fractured discipline will be dominated by tight
clusters based on specific research problems
•An integrated discipline will have strong
connections bridging research problems
Introduction
Outline:
•Introduction
•Theoretical perspectives on scientific development
•Network basis of social cohesion
•Data Sources
•Results
•Where Does Sociology fit? Journal co-citation networks
•What do sociologists study? Topic networks
•Who produces sociology? Social science collaboration networks
•Discussion
Approaches to Understanding Scientific Coherence
•Normal Science, accumulation & revolution
-Science is problem driven & evidence based
-Consensus emerges through a competition of ideas against data
-(though lab ethnography repeatedly shows that consensus is often more
socially constructed than evidentiary)
-Scientific “Star” systems reward prior success, and stars shape research agendas
•Boundary Specification & Science as a profession
-Motivated by prestige & competition for resources
-Competition will lead to both vanquishing and niche filling
-Disciplinary identity & coherence become a key issue
-Contested fields lead to “chaotic” outcomes (Abbott 2001)
•Invisible Colleges
-Informal communities create acceptable scientific standards
-Boundaries are defined socially through interaction
•Scientific (social) Movements
-Combination of many of these ideas under a social movement frame
-Coherence becomes a framing & “grievance” issue used to shape resource
allocation
Approaches to Understanding Scientific Coherence
Four relevant networks:
1.
Citation networks – a direct trace of scientific recognition &
production
2.
Topic networks – clusters of scientific products speaking about the
same subject
3.
Collaboration networks – “invisible communities” of social
interaction that produces scientific products
4.
Research Communities – People linked through common research
topics (merger of 2 & 3)
Approaches to Understanding Scientific Coherence
The field of sociology can thus be thought of as the intersection of
multiple networks.
The shape of these networks differs across scales and over time.
- Differences between local and global visions of the network
shape our perceptions of scientific coherence.
-
We tend to perceive coherence in our own specialty fields
and incoherence for the entire discipline.
-
A globally federated structure, that cannot easily exclude
empirical topics, might still be socially coherent if scientific
mixing cross-cuts empirical problems.
We can see this structure by examining these 4 networks at large
scale and over time.
Data Sources
•Citation Networks
•Compiled from the ISI web of science Journal citation tables
•Covers 1681 social science journals indexed in 2003
•Topic & Collaboration Networks
•Compiled from Sociological Abstracts
•281,163 papers published between 1963 and 1999
•Contains information on title, abstract, keywords, author(s), tables,
journal & citation
Where does sociology fit?
•Perennial debates over the existence of a theoretical core
•Rapid growth in the internal diversity of topics sociologist study:
50
45
Number of ASA Sections
40
35
30
25
20
15
10
5
0
1950
1960
1970
1980
1990
2000
2010
Where does sociology fit?
•Perennial debates over the existence of a theoretical core to the
discipline
•Rapid growth in the number of journals relevant to sociologists:
Where does sociology fit?
This growth & diversity has been seen as evidence for the ultimate
emptiness of sociology as a scientific discipline.
But disciplines are shaped by the connections between ideas, not the
number of ideas. That is, we recognize fields by who they speak to as
much as by what they speak about.
The clearest empirical trace of this communication is citation.
Disciplines can then be defined as clusters of work that speaks more to
each other than to anyone else.
Where does sociology fit?
Building co-citation networks
Links in a co-citation
network are constructed by
measuring how similar each
journal is to every other
journal.
Similarity is gauged by
correlating the pattern of
citations received by each
journals from every other
journal.
AJS ASR AER … JER
J1
#
#
0
0
J2
#
#
0
0
J3
0
0
#
#
J4
.
.
.
JER
0
#
#
#
0
0
#
#
Comparing across columns tells us whether the two
journals are recognized by others as similar.
Where does sociology fit?
Building co-citation networks
Links in a co-citation
network are constructed by
measuring how similar each
journal is to every other
journal.
Similarity is gauged by
correlating the pattern of
citations received by each
journals from every other
journal.
AJS ASR AER … JER
AJS
1.0
ASR
High 1.0
AER
.
.
.
JER
Low Med
1.0
Low Low High
1.0
This create a valued network of ties between two
journals. I use a cosine similarity score developed
in bibliometrics, selected for those with ties > 0.45
& at sharing at least 2% of their citation volume.
Where does sociology fit?
Economics co-citation similarity network
Density = 0.197
N=152
Isolates (not shown): 5
Node size proportional to log(degree)
Where does sociology fit?
Political Science co-citation similarity network
Density = 0.160
N=69
Isolates (not shown): 10
Node size proportional to log(degree)
Where does sociology fit?
Sociology co-citation similarity network
Density = 0.140
N=69
Isolates : 7
Where does sociology fit?
Where does sociology fit?
Where does sociology fit?
Where does sociology fit?
•Sociology “fits” at the center of the social sciences. We are not as internally
cohesive as Economics or Law, but more so than many (anthropology, allied
health fields).
•This represents a tradeoff. We have traded unique dominance of a topic
(markets, politics, mind, space, history) for diversity & thus centrality.
•Sociology is interstitial discipline (Abbott, 2004) in at least two-senses:
•There is no content topic we can reasonably exclude
•We pull together, and generate, the ideas and topics covered by
specialty disciplines.
•This makes us uniquely positioned to provide comprehensive insights on
particular empirical questions.
What do sociologists study?
If the citation networks capture the structure of organized disciplines, how do
we capture the internal organization of disciplines around research problems?
•Could use paper citation networks (see Hargens 2000), but data are
difficult & expensive to obtain for large-scale networks.
•Can examine the network of papers formed by the topics they write
about.
•Directly taps scientific content
•Purely endogenous creation of topics that allows new topic areas to
emerge and old ones to die over time
•Data can be extracted from information held in Sociological
Abstracts
•Multiple levels:
•Coarse grained Focus solely on keywords
•Fine grained  Use all information available (title,
abstract, keywords)
What do sociologists study?
A coarse grained view
What about the topic distribution within core sociology journals?
Source: Ryan Light, “Balkanized or Boundless” MA Thesis, OSU. Journals restricted to the 79 identified by
Allen (2003) as core sociology journals
What do sociologists study?
A coarse grained view
Source: Ryan Light, “Balkanized or Boundless” MA Thesis, OSU. Journals restricted to the 79 identified by
Allen (2003) as core sociology journals
What do sociologists study?
A coarse grained view
Source: Ryan Light, “Balkanized or Boundless” MA Thesis, OSU. Journals restricted to the 79 identified by
Allen (2003) as core sociology journals
What do sociologists study?
A coarse grained view
Source: Ryan Light, “Balkanized or Boundless” MA Thesis, OSU. Journals restricted to the 79 identified by
Allen (2003) as core sociology journals
What do sociologists study?
A fine grained view
Index entries contain title, abstract and keywords that summarize the
paper’s content.
•Map paper-to-paper networks for all papers indexed within four 3-year
windows from 1970 to 1999.
•Construct a paper – by – word matrix, where the ij cell lists how many
times word i is used to describe paper j.
•Word set is stemmed to get at root words
•A stop-list is used to minimize inclusion of meaningless English
words (“the” “and” “is” etc.)
•Construct a network by linking the most highly correlated papers
•Use correlation of 0.40 or better
•Ties are treated as valued in the network analyses
•Use network clustering algorithms (Moody 2001) to identify highly
cohesive clusters in the resulting networks and contour sociograms to give
an intuitive sense of how topics have changed over time
What do sociologists study?
A fine grained view
Example: One-step neighborhood of “More information, better jobs?”
What do sociologists study?
A fine grained view
Example: One-step neighborhood of “More information, better jobs?”
What do sociologists study?
A fine grained view
What do sociologists study?
A fine grained view
What do sociologists study?
A fine grained view
What do sociologists study?
A fine grained view
What do sociologists study?
A fine grained view
Cluster Size Distribution
% Clustered: 72.2
% Clustered: 71.1
% Clustered: 72.5
% Clustered: 74.9
What do sociologists study?
A fine grained view
We can measure the degree of consensus in words used to describe
papers with:
C = S pi2
Where pi is the proportion of times word i is used
What do sociologists study?
A fine grained view
Consensus Scores
1970 - 1999
0.13
C (x 100)
0.125
0.12
0.115
0.11
1965
1970
1975
1980
1985
1990
1995
2000
What do sociologists study?
The cluster structure of the topic network for the broader body of
sociologically relevant work has remained largely constant:
•About 70% of papers can be clearly assigned to a strong topic
cluster over the last 30 years.
•The basic number of clusters has hovered around 110 in all periods,
with some no strong indication of growth in number.
•Almost all growth can be accounted for in larger clusters.
•The ~30% of papers that are not embedded in clusters either span
multiple well established boundaries or belong to very small niches.
What do sociologists study?
The cluster content of the topic network has evolved slowly:
•Some clearly central specialties have remained prominent over the
entire period. This includes larger areas such as:
• Class & Stratification
• Race & Ethnicity
• Education
• Gender (Strongest from 1980s on)
• Family (Strongest from the 1980s on)
• Crime
As well as clearly distinct, though numerically smaller bodies of
research related to
• Suicide
• Sociology of Science, Technology & “Reflexive” sociology
• Unions
What do sociologists study?
The cluster content of the topic network has evolved slowly:
•The clearest change has been the rapid growth of social research on health.
•Dominated by a very large body of research related to HIV/AIDS
•Includes research on all social aspects (discrimination, coping,
education, etc) as well as directly health-related work.
•Other areas of relative growth include:
•Family topics were most prominent in the 1980s
•A strong presence of research on sex & sexuality emerged in the
1980s and 90s
•Relative declines have come in areas such as:
• Groups
• Interaction
• “Radical” studies
• Elite studies
Summary: A move away from basic social processes toward studying social problems,
with a growing uniqueness of theory & method
What do sociologists study?
A clustered topic structure focused strongly on practical problem solving has a hint of
Durkheim’s concern: Is there any integration across these topic clusters?
We shouldn’t jump too quickly to that conclusion:
•
Topic clusters are formed from papers, and papers typically have well
encapsulated ideas. They have a small “maximum digestible unit”
•
Scientific integration is really about how scientists bridge these multiple
topics.
•
If authors write and collaborate across these topics then ideas, methods
and approaches can quickly disseminate as well.
Two aspects to this question:
•
The structure of the collaboration graph – if this is highly clustered it would
signal potential fragmentation  Who produces sociology?
•
The dual graphs of topics linked through authors.
Who produces sociology?
Science is typically produced through collaboration, both formally and
informally (Crane 1972, Crane & Small 2000, Friedkin 1998).
The best empirical trace of collaboration for large communities of science is
coauthorship.
•Misses the less intense collaborations recognized in acknowledgements,
discussions, colleagues reading each other’s work
•But should provide the strongest test of a clustering hypothesis, since the
set of people we write with should be more like us than the set of people
we have lunch with or discuss share work with informally.
•There are differences across subfields in formal collaboration rates,
which, if anything, should magnify the extent of observed
fragmentation.
Who produces sociology?
Coauthorship Trends in Sociology
Sociological Abstracts and ASR
Proportion of papers with >1 author
0.75
0.6
0.45
0.3
Sociological Abstracts
ASR
0.15
0
1930
1940
1950
1960
1970
Year
1980
1990
2000
Who produces sociology?
Distribution of Coauthorship Across Journals
Child
Development
Sociological Abstracts, 1963-1999
Proportion of papers w. >1 author
1
0.8
Soc.
Forces
J. Health &
Soc. Beh.
ASR
0.6
J.Am.
Statistical A.
0.4
AJS
Atca
Politica
Soc.
Theory
0.2
Signs
J. Soc.
History
0
0
100
200
300
400
500
600
700
Coauthorship Rank
800
900
1000
1100
Who produces sociology?
Who produces sociology?
Construct a collaboration network by assigning an edge between
any pair of people who coauthored a paper together.
g=745
Who produces sociology?
Example Paths: 3-steps from N. B. Tuma
Node size = ln(degree)
g=745
Who produces sociology?
The simplest summary test for a fragmented network is to measure the extent of
clustering in the network. Watts’ work on the “small-world problem” suggests that if
the collaboration network is a small world network it might be fractured.
C=Large, L is Small =
SW Graphs
•High relative probability that a node’s contacts are connected to each other.
•Small relative average distance between nodes
Who produces sociology?
In a highly clustered, ordered
network, a single random
connection will create a shortcut
that lowers L dramatically
Watts demonstrates that Small
world properties can occur in
graphs with a surprisingly small
number of shortcuts
Who produces sociology?
Locally clustered graphs are a good model for coauthorship
when there are many authors on a paper.
Paper 1
Paper 2
Paper 3
Paper 4
Paper 5
Newman (2001) finds that coauthorship among natural scientists
fits a small world model.
I test this model on the sociology coauthorship network,
using all authors from 1963 – 1999.
Who produces sociology?
Clustering
Distance
Observed
Random
0.194
0.206
9.81
7.57
The sociology network less clustering than would be expected
by chance and somewhat longer overall distances.
This suggests that it does not have a small-world structure.
Who produces sociology?
The network has a broad Core-periphery structure
(68,923)
59,866
38,823
29,462
Bicomponent
Component
Unconnected
Structurally Isolated
Who produces sociology?
Largest Bicomponent, g = 29,462
0.04
0.27
0.50
0.73
0.96
Who produces sociology?
Health
General
Sociology
Who produces sociology?
Who produces sociology?
Internal Structure of the largest bicomponent
Group 1
Size
3667
In-group / out- group ties
3.24
% male
67
Years in discipline
8.46
Number of co-authored publications
5.32
Group 2
987
2.86
52
4.67
3.24
Who produces sociology?
Internal Structure of the largest bicomponent
5+ -connected
5,223
4-connected
7,992
3-connected
14,672
2-connected
29,462
0
10
20
30
40
Who produces sociology?
Characteristics of authors by component embeddedness
Structural
Total
Isolate
(0)
Percent male
62%
69%
(a)
Years in the discipline
4.02
2.88
Avg. number of authors per paper
2.26
1.0
Number of publications
2.17
1.51
Number of co-authors
2.05
0.00
Year of first publication
1985.85
1984.5
N
197074
68932
Unconnected
(1)
62%
3.44
2.57
1.76
1.95
1986.6
59,866
Largest
component
(2)
56%
3.98
2.83
2.02
2.48
1986.6
38,823
Core
bicomponent
(3)
59%
7.97
3.78
4.78
6.49
1986.18
29,462
Who produces sociology?
•Strong specialty effects for ever-coauthored
Unlikely:
History & Theory
Sociology of Knowledge
Radical / Marxist Sociology
Feminist / Gender Studies
Likely:
Social psychology
Family
Health & Medicine
Social Problems
Social Welfare
Who produces sociology?
•Weak specialty effects for network embeddedness
•Large number of coauthors increases embeddedness
•Large number of people on any given paper decreases
embeddedness
Who produces sociology?
Graph Connectivity, Cumulative 1963 - 1999
0.6
% in Giant Component
0.5
Percent
0.4
% of connected
in bicomponent
0.3
0.2
0.1
0
1965
1970
1975
1980
1985
Years (1963 - date)
1990
1995
2000
Who produces sociology?
Network Connectivity: 5-year moving window
0.4
2.25
0.35
2.2
Percent
0.25
2.15
0.2
2.1
0.15
0.1
Connectivity
Bicomponent
0.05
2.05
Component
0
1975
1980
1985
1990
Year
1995
2
2000
Connectivity
0.3
Knowledge Accumulation in Sociology?
Social Science Citation Structure
•Economics, Psychology, Business/Management are most cohesive
•The are also “peripheral” in that they speak to a relatively
limited set of problems
•Sociology is as cohesive as Political Science, and more cohesive
than fields such as Anthropology, Social Work, Education or allied
health fields that all have more limited empirical domains
•Sociology has made a tradeoff between internal cohesion and
external centrality.
Knowledge Accumulation in Sociology?
Scientific Topic Network
•Big-Picture: A general progression towards problem solving and
the specialization of work on theory & methods.
•Fine-grained structure:
•A federated topic structure that has remained constant since the
1970s, with about 70% of all papers being clearly clustered.
•Key content areas have remained largely constant
•Race, Family, Class, Gender, Science,
•A decrease in focus on general foundation problems
•Group structure, community, interaction
•An increase in work on social problems
•Health & HIV/AIDS -related topics
•Some evidence for greater homogeneity in topics discussed
Knowledge Accumulation in Sociology?
Scientific Collaboration Network
•The networks is not divided into small research-area based clusters.
•There is no partition that strongly separates scientists, which
implies that authors cross topics.
•This is good for social cohesion.
•There is some evidence for a division based on research method,
with largely quantitative work more likely to be coauthored.
Knowledge Accumulation in Sociology?
Combined, these models suggest a discipline that is socially integrated
globally and strongly cohesive at the local topic level.
Discipline-wide integration will likely only increase as pressures for
collaboration push more scientists to work together across topics.
The perception of disintegration will likely continue, however, because
most of us only read other areas in the main general journals. But almost
all of the topical cohesion is due to the “normal science” occurring in
specialty journals.