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.