Complex Systems 270
Patrick Grim
Agent-Based Modeling
B844 EH MW 10-11:30
This is a ‘doing’ course with a wealth of background information added: a hands-on introduction
to some landmark models, the core concepts, and the central techniques of agent-based
modeling.
Agent-based modeling has established itself as a powerful exploratory tool in the formal,
physical, and especially the social sciences. Epidemics. Riots and Revolutions. Ecological
Dynamics. Environmental Crises. Innovation and New Ideas. The Spread of Terrorism. Fads
and Rumors. Evolution. Scientific Networks. Cooperation and Conflict. Opinion Polarization.
Traffic Jams. Climate Crises. Market Volatility and Economic Bubbles.
We are surrounded by cases of complex phenomena on one level that may be the result of
simpler components following simpler patterns on a level lower down. That is precisely what
agent-based modeling is all about.
At the conclusion of the course, you will:
1) have incorporated the basic concepts of complex systems
2) be familiar with classic literature and some current work in agent-based models
3) be proficient in the programing language of NetLogo
4) be designing and implementing your own agent-based models
Work for the course will be divided between (1) lecture and discussion sections on concepts
and landmarks in agent-based modeling and (2) work sessions in which teams develop their own
project work.
● Lecture sheets and active participation in class will constitute 20% of your grade.
● Homework will be assigned just about every session and will constitute 30%.
● Project grading will constitute 50% of your grade.
There will be three projects over the course of the semester, increasingly
challenging but with increasing liberty as well. In order, the three projects will
constitute 20%, 35%, and 45% of your project grade.
There will be a way to lose points: I will take attendance each time, and reserve the right to
deduct 2% of your grade for every unexcused absence. Because this is a hands-on course, it is
important that we have all hands on deck every time.
Topics in order by week and session:
Week 1
1. Welcome to the Course
From Vaucanson’s Duck to John von Neumann:
The backroom history of agent-based modeling
Wednesday, Sept. 9
2
Homework #1, due in hard copy on Monday, Sept. 14:
Download NetLogo
The Party Model and questions
Week 2
2. Agent-Based Modeling: the Fundamental Concepts
Emergence
Chaos
Complexity
Heroes and Cowards
Monday, Sept. 14
Homework #2, due in hard copy on Wednesday, Sept. 16: NetLogo Tutorial #1 and
questions
3. The Game of Life
Introducing John Horton Conway and his tongue
Two-dimensional cellular automata
The philosophy of modeling
Wednesday, Sept. 16
Homework #3, due in hard copy on Monday, Sept. 21: Tutorial #2, part of #3, and questions
Week 3
4. Cellular automata
A third strange person: Steven Wolfram
Even simpler: one-dimensional cellular automata
The Four Wolfram categories
Monday, Sept. 21
Homework #4, due in hard copy on Wednesday, Sept. 23: Tutorial #3 with questions
5. ABM workshop #1
► First Project is assigned (“the envelope please”),
First Project due Monday, Oct. 5
Wednesday, Sept. 23
Homework #5 Reading: Robert Axelrod, from The Evolution of Cooperation
Questions on the reading due online Monday, Sept. 28
Week 4
6. Decision and Game Theory
Decisions, decisions
Economic rationality
Monday, Sept. 28
3
The beautiful mind of John Nash
Homework #6: due in hard copy on Wednesday, Sept. 30h: Introducing Behaviorspace
7. ABM workshop #2
Wednesday, Sept. 30
Homework #7, due Monday October 5th
October 5th
Prepare presentation and write-up for Monday,
Week 5
●
8.
First Project Presentations
A 10-minute report on your first project
Write-ups due
Monday, Oct. 5
20% of project grade
Homework #8 Reading: from Richard Dawkins, The Selfish Gene, chapters 2 and 11
Questions on the reading due online Wednesday, Oct. 7
9. Replicator dynamics and evolutionary game theory
The Evolutionary Algorithm
Replicators and replicator dynamics
Stealing evolution’s thunder: Genetic algorithms
Wednesday, Oct. 7
Homework #9: Reading: Martin Nowak & Robert May, “Evolutionary Games and Spatial
Chaos”
Bernardo Huberman & Natalie S. Glance, “Evolutionary Games
and Computer Simulations”
Questions on the readings due online Monday, Oct. 12
Week 6
10. The Devil in the Details
Synchronous and asynchronous updating
Differential and difference equations
When timing makes a difference
Monday, Oct. 12
Homework #10: Reading: “The Evolution of Generosity in a Hobbesian Model,” from
Grim, Mar & St. Denis, The Philosophical Computer.
Questions on the reading due online Wednesday, Oct. 14
11. Game Theory meets Cellular Automata
Wednesday, Oct. 14
4
The Spatialized Prisoner’s Dilemma
The Stochastic Prisoner’s Dilemma
Homework #11: Reading: Thomas C. Schelling, “A Self-Forming Neighborhood Model”
from Thomas C. Schelling, Micromotives and Macrobehavior
Questions on the reading due online Wednesday, Oct. 21
Week 7
Reading period
Monday, Oct. 19
12. De Facto Segregation
Introducing Thomas C. Schelling
What does the model prove?
Wednesday, Oct. 21
► Second Project assigned. Second Projects due Monday, Nov. 9
Homework #12: Due in hard copy on Monday, Oct. 26: Behaviorspace on the
Spatialized Prisoner’s Dilemma
Week 8
13. ABM workshop #3
Monday, Oct. 26
Homework #13: Reading: Grim, Selinger, Braynen, Rosenberger, Au, Louie, &
Connolly, "Modeling Prejudice Reduction: Spatialized Game Theory and the Contact
Hypothesis"
Questions online due Wednesday, Oct. 28
14. Are You Prejudiced?
How do you get rid of prejudice?
Modeling the Contact Hypothesis
Wednesday, Oct. 28
Homework #14: Working on your model
Week 9
15. ABM Workshop #4
Monday, Nov. 2
Homework #15: Reading: Duncan Watts, “Small Worlds,” from Six Degrees: The
Science of a Connected Age
5
Duncan Watts & Steven H. Strogatz, “Collective Dynamics
of ‘Small World’ Networks
Questions on the reading online due Wednesday, Nov. 4
16. Properties of Networks
The Oracle of Bacon
Stanley Milgram and 6 Degrees of Separation
Small Worlds
Wednesday, Nov. 4
Homework #16: Preparing your presentation and write-up for the Second Project
Week 10
17.
●
Second Project Presentations
A 10-minute report on your second project
Write-ups submitted
Monday, Nov. 9
35% of project grade
Homework #17: Hard copy due Monday, Nov. 11th: Small worlds and
preferential attachment in NetLogo
Reading: from Albert-László Barabási, Linked: The New Science
of Networks
Albert-László Barabási & R. Albert, “Emergence of scaling in random
networks”
Questions on the reading due online Wednesday, Nov. 11
18. The Rich Get Richer
Citations, city sizes, and sexual networks:
Power laws and scale free networks
Wednesday, Nov. 11
Homework #18:
Reading: Robert Axelrod, “The Dissemination of Culture: A Model with Local
Convergence and Global Polarization”
Questions on the reading due online due Wednesday, Nov. 16
Week 11
19. Why are we so alike? Why are we so different?
Polarization, causes and cures
Models for opinion dynamics
Monday, Nov. 16
Homework #19: Hard copy due Wednesday, Nov. 18: viral infection on a network
Reading: from Grim, Singer, Fisher, Bramson, Berger, Reade, Flocken & Sales,
6
“Scientific Networks on Data Landscapes: Question Difficulty,
Epistemic Success, and Convergence”
From Scott Page, The Difference
Questions on the reading due online due Wednesday, Nov. 18
20. Modeling Scientific Exploration
Wednesday, Nov. 18
Diffusion on networks: cooperation and ideas
Can science learn more when scientists learn less?
Diversity versus Expertise on Epistemic Landscapes
Homework #20: ‘My Crazy Ideas for the Third Project,’
Question / staggered set of questions
Strategy for modeling
Format for results?
Your own 2 pages due hard copy due Monday, Nov. 23.
Week 12
21. Model Design and Consultation
Monday, Nov. 23
► Choosing teammates toward Third Project
Design project: topic area
Question / staggered set of questions
Strategy for modeling
Format for results?
Wandering consultation
Third Project Due Wednesday, December 9th
Homework #21: ‘My Team’s Crazy Idea for the Third Project’
Question / staggered set of questions
Strategy for modeling
Format for results?
3 page project prospectus per team due hard copy Monday, Nov. 30
Wednesday: Thanksgiving, with remote team consultation on the project prospectus
Week 13
22. ABM workshop #5
► Your team’s project prospectus due
Monday, Nov. 30
Homework #22: Prepare for final presentations and write-ups, due Wednesday, Dec. 9th
7
23. ABM workshop #6
Wednesday, Dec. 2
Homework #23: Prepare for final presentations and write-ups, due Wednesday, Dec. 9th
►
Posters due in IT print shop Wednesday, Dec. 9
Week 14
24.
● Third project presentations
45% of project grade
25.
● Third project presentations
45% of project grade
Monday, Dec. 7
Wednesday, Dec. 9
Week 15
26. ● Poster presentations
Complex Systems Advanced Academic Workshop
Counts as final write-up
Monday, Dec. 14
Midterm and Final: There is no midterm or final. This is a course evaluated not in terms of
your mastery of past territory but your creative and rigorous exploration of new territory.
Textbooks: There are no textbooks. I will be giving you bits and pieces of classic material that
form the conceptual and historical background for what you’ll be doing…the giants on whose
shoulders I want you to stand.
Further notes:
The core of the course is your original work, with increasing challenges and increasing liberties
as the semester goes on. For most projects, I will outline a ‘target’ expectation: what I suggest
that you aim for. That target, however, will almost always represent merely a ‘B’ level, 85%
type goal. A’s on projects are reserved for innovative, original, and creative work above and
beyond an assigned task. So when the question is ‘How come we didn’t get an A on our
project—we did everything you asked?’ the answer is ‘Because what I wanted was to you to go
further, to dig deeper, to think bigger…to do something beyond what I asked.’
Modeling is ultimately about thinking…and thinking takes time. I have tried to give you original
sources for readings in this course, at a professional level, whenever possible. Sometimes those
are a little stiff—you will need patience and careful thinking…and thinking takes time. Make
sure you carve out space not merely to sail through your work, but to really think about it. That
will make all the difference in what you get out of our work together.
8
Me: My office is in West Hall 323. I work there, so I’m there a lot, but we’ll make official
office hours 1:00 – 3:00 Monday and Wednesday. If you need me any other time, or need to
contact me in any other way, the best-email, peculiarly enough, is patrick.grim@stonybrook.edu.