Week 11 - Communities in Networks

Dad Joke

The guy who stole my diary died yesterday.

My thoughts are with his family.

Housekeeping

• Make an appointment for Self Assessment Reflection review
• Submit Exam Questions ASAP
• Internet technologies demo on Thursday
• Exam April 17
• Exam review April 10

Plan for today

• Groups in networks review
• Discussion questions
• R

Community Detection Review

• What is a component? (Hint: there’s often one “giant” component)
• What is a clique?
• What is the weakness of cliques as a way of identifying groups?
• What is a k-plex? (Hint: related to cliques)
• The goal of most community detection algorithms is high modularity. What does that mean?

Core and Periphery Review

• Why do groups often have a core and a periphery?
• Given some of the other theories we’ve talked about, how would you expect the periphery to differ from the core?
• What role does the periphery have in protests (Barberá et al. reading)?
• What is one way to identify who is in the core or periphery?

Coreness Example

Discussion Questions

• How can random walks identify communities?
• Do k-plexes really happen? Are you really connected to everyone but one person?
• Do all groups have a periphery?
• Clustering coefficient
• Rich club coefficient
• Homophily vs. cliques

Visualization Challenge Review

• Glanced at a handful and they are quite good!
• Discussion about LLMs and coding
  • I have been intentionally vague
  • I want you to learn computational thinking, learn syntax of R
  • I also want you to learn how to use AI to do cool stuff!
  • I’m torn about what to expect / how to encourage
  • Fundamental knowledge makes AI stuff easier

Further AI discussion

• Similar concerns about AI-augmented reading.
  • AI can help us to understand deeper, or to pretend that we understand deeper.
  • How can instructors encourage the former?