What is Social Network Analysis?

1. Social network analysis is motivated by a structural intuition,

2. It is grounded in systematic empirical data,

3. It draws heavily on graphic imagery, and

4. It relies on the use of mathematical and/or computational

models.

Structural Intuitions:

• Alex Bavelas—Productivity, Leadership and Morale

• Torsten Hagerstrand—Information & Space

• Elizabeth Bott—Support and Control

• Peter Blau—Homophily

• Mark Granovetter—Social Organization

Bavelas’ Centrality

Bavelas’ Apparatus

• The greater the centrality:

– The faster the solution– The fewer errors– The lower the morale

Structural Intuitions:

• Alex Bavelas—Productivity, Leadership and Morale

• Torsten Hagerstrand—Information & Space

• Elizabeth Bott—Support and Control

• Peter Blau—Homophily

• Mark Granovetter—Social Organization

Hagerstrand—Spatial Diffusion

•Census data on the spread of an innovation in space

• Wave-like patterning

•Assumed pair-wise process

•Distance/decay in contact

•Estimated by addresses of brides and grooms

Structural Intuitions:

• Alex Bavelas—Productivity, Leadership and Morale

• Torsten Hagerstrand—Information & Space

• Elizabeth Bott—Support and Control

• Peter Blau—Homophily

• Mark Granovetter—Social Organization

Bott:

Support

and

Control

Loose Knit

Tight Knit

Bott:

Support

and

Control

Loose Knit

Tight Knit

Structural Intuitions:

• Alex Bavelas—Productivity, Leadership and Morale

• Torsten Hagerstrand—Information & Space

• Elizabeth Bott—Support and Control

• Peter Blau—Homophily

• Mark Granovetter—Social Organization

Blau’s Homophily [Moreno Data]

Structural Intuitions:

• Alex Bavelas—Productivity, Leadership and Morale

• Torsten Hagerstrand—Information & Space

• Elizabeth Bott—Support and Control

• Peter Blau—Homophily

• Mark Granovetter—Social Organization

BREAK

Graph

Ordered pair: G = <A, R>

Symmetric

If <a1 , a 2> R then <a2 , a 1> R

For all A, if a1 R a 2 then a2 R a 1

Nonsymmetric

• For at least 1 element in A, a1 R a 2 and a2

R a 1

• For at least 1 element in A, a1 R a 2 and a2

~R a 1

Binary

1922 Almack

Valued

1999 Brewer & Webster

Existing Records

1986Breiger & Pattison

Subjects’ Reports

1992Fagan

1999Brewer & Webster

Systematic Observation

1988Freeman, Freeman & Michaelson

Recording Devices

2004Bulkley & van Alstyne

Experimental Manipulation

1951Leavitt

Ethnographic Notes

1956Bott

Free Listing

1999Brewer & Webster

Forced Choice

1999Brewer & Webster

Card Sorts

1988Freeman, Freeman & Michaelson

Spatial Tasks

1994Freeman

Reports about Self

1922Almack

Reports about Everyone

1987Krackhardt

Systematically Compared

1976Killworth & Bernard