CMPLXSYS 530 - Computational Modeling of Complex Systems

Course information

Course time & location

Tuesdays and Thursdays, 1 - 2:30pm
Weiser Hall 269
The course will be in person, but some office hours and occasional course meetings may also be held via zoom as needed, at: https://umich.zoom.us/j/95806757765 (password information is on Canvas)

Instructors & office hours

Instructor: Prof. Marisa Eisenberg (she/her)
- Email: marisae@umich.edu
- Office Hours - Weiser Hall 735
  - Typically after class, for an hour on Tuesdays and a half hour or an hour on Thursdays depending on the week (but we can set up other times as needed if those don’t work)
  - Usually in person but sometimes via zoom (link above)
GSI: Conrad Kosowsky
- Email: coko@umich.edu
- Office Hours
  - Regular office hours: 703 Weiser Hall
    - Tuesday 10:30am-11:30am
    - Tuesday 3:30pm-4pm
    - Thursday 3:30pm-4pm
  - By appointment in 715A Weiser Hall

Syllabus

Syllabus - includes course overview, grading information, prerequisites, etc.

HW/Lab information

HW/Lab guidelines - guidelines on how to turn in your HW assignments, what needs to be turned in, and the grading rubric we will use. Note that assignments are turned in via Canvas!
Final project information - information on the course final project (will be updated as we go)
Final project proposal template

Course topics

Topics are subject to change and rearrangement! (We may also not get through all the topics listed)

Lecture slides, links to assignment instructions, and readings will be posted in each topic as we get to them.

1. Introduction to agent-based models (ABMs)

Topics covered: overview of basic concepts, coding intro, why model?, intro to ABMs and their pros/cons, philosophy of complex systems, emergent behavior/phenomena, classic examples in biological, social, and physical systems, etc.

Lecture 1: Introduction and overview
- Slides - what are models, why model, emergent behavior, complex systems
- Emoji simulator: forest fire model, blank model, more models!
- Readings
- To Do: Get comfortable with python if you haven’t used it much! You can use Google Colab to get started or install python on your computer (e.g. the Anaconda distribution). See the Additional useful info section below for tutorials and more info!

Lecture 2: Introduction to Agent-Based Models
- Slides - how to choose a modeling framework, intro to ABMs
- Readings
  - Think Complexity, Chp. 1
  - Wilensky and Rand, Chp. 2
  - Considerations and Best Practices in Agent-Based Modeling to Inform Policy (gives a nice introduction to the PARTE framework for thinking about ABMs)

Lecture 3: Case study: Modeling the Ancestral Puebloan communities of Long House Valley (the Artificial Ancestral Puebloan Project (AAP))
- Slides
- Readings
  - Papers on the AAP (see also the references in the slides)
    - Axtell et al., PNAS, 2002. Population growth and collapse in a multiagent model of the Kayenta Anasazi in Long House Valley
    - An interesting replication study that examines some of the issues and underpinnings of the AAP: Janssen, JASSS, 2009. Understanding Artificial Anasazi

Lab 1: Introduction to ABMs, NetLogo, and Python
- Lab 1 Assignment
  - For emoji, you can copy-paste from here: https://emojipedia.org/
  - Quick intro to NetLogo
  - Template code for the Python portion
- Readings
  - Wilensky and Rand, Chp. 3-4

Intro to the PyCX library for simulating complex systems models in Python
- Intro to PyCX (pdf version)
- Download from the PyCX GitHub
- PyCX example files
  - PyCX Simulator file - 2019 version - use this if the current version causes issues!
  - PyCX model template script
  - PyCX voter model example
  - PyCX in Google Colab - Unfortunately the GUI part of PyCX doesn’t run in Google Colab, but this demonstrates how to run PyCX files in Colab or other Jupyter notebook types of things.
- Readings
  - Sayama, Chp. 10
  - Sayama, H. (2013). PyCX: a Python-based simulation code repository for complex systems education. Complex Adaptive Systems Modeling, 1(1), 1-10.

Extra Notes: Chaos Game!
- Board notes
- Interesting links & extra things
  - Chaos game simulator - lets you try out chaos games with other shapes and settings, also includes some proofs for why the Chaos Game works
  - Another chaos game example
  - A somewhat systematic exploration of some chaos game simulations
  - Barnsley fern
  - Sierpinski Tetrahedrons
  - Neat fractal landscapes

2. Cellular automata

Topics covered: overview of basic cellular automata (CA) concepts, emergent behavior, classes of CA, examples of CA (e.g. Conway’s Game of Life), coding and analysis methods for CA, applications

Lecture 4: Intro to cellular automata
- Slides
- Readings
  - Sayama, Chp. 11
  - Think Complexity, Chp. 6
- Miscellaneous interesting things

Lecture 5: Cellular automata dynamics

Lab 2: Cellular Automata and Intro to Networks
- Lab 2: Cellular Automata & Intro to Networks
- A collection of 1-dimensional cellular automata
- Basic commands for networks in NetworkX/Python and NetLogo
- NetworkX tutorial (from the NetworkX documentation)
- Network data from Mark Newman

3. Networks

Lecture 6: Introduction to Networks

Lecture 7: Random networks, dynamics on networks and of networks

Lecture 8: Adaptive networks, mean-field approximation of networks

Lab 3: Network Dynamics
- Lab 3: Dynamics on and of Networks

4. Parameter sweeps, sampling, and sensitivity analysis

Lecture 9: Sampling, visualization, uncertainty
- Slides
  - Example code - Latin hypercube sampling with an SIS network model
- Readings
  - PARTE (Properties, Actions, Rules, Time, Environment) framework
  - ODD (Overview, Design concepts, and Details) Protocol
  - Yang Y, Roux AV, Auchincloss AH, Rodriguez DA, Brown DG. A spatial agent-based model for the simulation of adults’ daily walking within a city . American journal of preventive medicine. 2011 Mar 1;40(3):353-61.

Lecture 10: Sensitivity analysis
- Slides
- Example code - Sensitivity analysis with the SIS network model
- Readings
  - Marino, Simeone, et al. “A methodology for performing global uncertainty and sensitivity analysis in systems biology.” Journal of theoretical biology 254.1 (2008): 178-196.
  - A nice table of different sensitivity analysis methods
  - The wikipedia page is also pretty comprehensive!
  - Active nonlinear testing

Jeff Dunworth Guest Lecture - Computational neuroscience: how network structure impacts function

Lecture 11: Analyzing Model Outputs
- Slides

Lab 4: Parameter sampling and sensitivity
- Lab 4: Parameter sampling and sensitivity
- Google Colab Predator Prey Model

Lecture 12: Parallel Computing
- Slides
- Example Code
- Additional tools for more advanced parallel computing:
  - https://numba.pydata.org/
  - https://dask.org/

5. Parameter estimation from data

Topics covered: parameter estimation, MCMC, parameter identifiability & uncertainty, model comparison (e.g. AIC/BIC/etc)

Lecture 13: Introduction to parameter estimation
- Thinking about the challenges of linking data with models, and what these approaches can (and can’t) tell you
- Maximum likelihood methods, optimization basics
- Slides
- Example code - Basic optimization
- Example code - Maximum likelihood

Lecture 14: Introduction to Bayesian parameter estimation & MCMC
- Sampling based methods, including basics of approximate Bayesian computation, sample importance resampling, MCMC (Markov Chain Monte Carlo), etc.
- Slides
- Example code - Basic MCMC
- MCMC Mean Field SIR Model
- MCMC Mean Field SIR Model - Identifiability Issues
- ABC Rejection Sampling Example
- Readings
  - Menzies NA, Soeteman DI, Pandya A, Kim JJ. Bayesian methods for calibrating health policy models: a tutorial. PharmacoEconomics. 2017 Jun 1;35(6):613-24.
- A big compendium of packages to run MCMC in python

Lecture 15: Identifiability
- Slides
- Identifiability code examples

Lecture 16: Model selection and the AIC
- Slides

6. Advanced/additional topics

Potential Topics:
- decision/game theory
- chaos and fractals
- classic example complex systems models (Kuramoto oscillators, Sugarscape, etc.)
- more advanced environments (e.g. putting ABMs on GIS)
- active subspaces, dimension reduction
- model selection
- clustering, PCA
- machine learning and complex systems
- webpage scraping, basics of API’s, pulling data from various places (social media, google, government sources)

Lecture 17: Machine learning and AI
- Slides
- AI slides part 1
- AI slides part 2
- Readings
  - Artificial intelligence in medicine and the disclosure of risks, 2020. AI Soc. 2021; 36(3): 705–713.
  - Obermeyer et al 2019, Dissecting racial bias in an algorithm used to manage the health of populations
  - A nice series of articles on mechanistic interpretability

Lecture 19: Game & decision theory
- Readings

Lecture 20: Machine learning and AI
- Slides
- Code

Additional Materials: ABM Environments and Mapping/GIS
- Intro to mapping with Folium
- Predator-prey bubble tea example
- Mapping tutorials
  - Making 3 Easy Maps in Python - the point map example here may be particularly useful for visualizing agents on a map (where you can define their x,y locations in terms of e.g. latitude and longitude). This uses the module folium, which is one of the common mapping packages.
  - Making maps in Basemap This is another package for mapping, and you can similarly do point maps and plot other features on the map. The syntax for basemap seems pretty straightforward, so this may be a useful package to consider also. There’s an additional tutorial for Basemap here also.

Additional useful info

Useful links and extra readings will be posted here.

Coding and typesetting resources

Overall Coding Resources

NetLogo installation information
Python
- Anaconda distribution for Python
- Tutorials
  - 10-minute Python - very short tutorial with just the basics (often useful if you’ve coded in other things or have used python but not in a while)
  - The Python Tutorial - the official tutorial, gives more details and a good reference. Good to start with if you’ve never used python.
  - Think Python - the book is a good reference too—you may want to start with Chapters 2 and 3
  - A nice collection of python tutorials
- Spyder - the built in tutorial is pretty good! You can find it under the help menu
- Jupyter/IPython resources
  - Jupyter notebook site, a nice tutorial on using Jupyter notebooks

ABM Resources

Modules/packages for agent-based modeling
- PyCX module for Python (we will use this!) (reference for PyCX)
- CoMSES ABM Library - potentially useful for project ideas!

Math Resources

Typesetting math: \(\LaTeX\) resources from Paul Hurtado

Books used in the course

Introduction to the Modeling and Analysis of Complex Systems by Hiroki Sayama
Think Complexity by Allen Downey
Think Python by Allen Downey
An Introduction to Agent-Based Modeling by Uri Wilensky and William Rand (you may need to be on the UM network or connected to the VPN for the download to work)

Interesting papers and extra readings