1. Network Approaches John D. Prochaska, DrPH, MPH
UTMB Department of Preventive Medicine
& Community Health

2. Learning Objectives
To define a network and discuss the utility of analyzing networks rather than isolated individuals
To present examples of networks in real-world applications
To summarize key network measures commonly implemented in network analysis

3. What is a Network?
A structure made up of a set of actors and the dyadic ties among the actors
Examples include
Social networks
Organizational networks
Information networks
Complex networks of all of the above

4. Why do Network Analysis
Researched to understand the nature of relationships among actors, nodes, or other agents or organizations

5. Components of a Network?
Notes (or vertices)
Ties (or edges)
Strong (bi-directional, reciprocal)
Weak (uni-directional)
Pendants
Isolates
Attribute Data
Relational Data

6. The Internet in 2005

7. Spatial Network
Network of Facebook Friends circa Source: Wikimedia

8. Epidemiology / Disease Outbreak

9. Types of Relationships
Similarities
Membership
Same attitudes towards
Spatial location
Social Relations
Friend of
Knows about
Relative of
Interactions
Talked to
Helped
Flows
Information
Beliefs
Personnel
Resources

10. Network Measures - Individuals
Density
Centrality
Total degree
In degree
Out degree
Closeness
Betweeness

11. Network Measures – Network Level
Size
Network density
Network centrality
Reciprocity
Efficiency

12. Applications – Faculty Collaboration
Faculty Members that Attend Meetings Together

13. Applications – Faculty Collaboration
Same Group of Faculty Members that Develop Grant Proposals Jointly

14. Applications – Faculty Collaboration
Same Group of Faculty Members that Publish Together

15. Issues to Consider Who completes the survey and who do they represent
What are the boundaries of the network
Sampling

16. Summary
Examining networks provides key insight into the workings of a the larger system
Provides information beyond what can be gained by examining individuals as separate units
Can provide critical information for improving communication, collaboration, and efficiency