README.md

Example Models

This folder includes the accompanying resources for the chatper. For full book details, see: http://www.abmgis.org/.

To highlight some other modeling techiques in this foloder you will find three examples:

1. A Cellular Automata (CA) model: The Game of Life model (CA_LifeModifed_Example.nlogo)
2. A Discreet Event Simulation (DES): DES_Airport_Queue_Example.nlogo
3. A System Dynamics (SD) Model: System_Dynamics_Wolf_Sheep_Predation_Example.nlogo

More details about the models, references and links can be seen below.

Modified Game of Life

The orignal NetLogo Game of Life model (Wilensky, 1998) was modifed to allow for gridlines to be drawn (note the draw-gridlines procedure was coppied exactly from http://complexityblog.com/. The code for the procedure is as follows:

to draw-gridlines
  crt world-width [
    set ycor min-pycor
    set xcor who + .5
    set color 2
    set heading 0
    pd
    fd world-height
    die
  ]
  crt world-height [
    set xcor min-pxcor
    set ycor who + .5
    set color 2
    set heading 90
    pd
    fd world-width
    die
  ]
end

Below you can see the Graphical User Inteface (GUI) for the model (see: CA_LifeModifed_Example.nlogo) with the grid lines shown.

Airport Security Line Simulation

The irport Security Line Simulation was created by Bybee and Eng (2012). While the orignal website cannot be directly accessed it is viewable on the Internet Archive.

Below you can see the GUI for the model (see: DES_Airport_Queue_Example.nlogo).

To get an overview of DES_Airport_Queue_Example.nlogo model click on the image below to watch a YouTube movie:

System Dynamics Model

Wilensky (2005) NetLogo Wolf Sheep Predation is shown below (see: System_Dynamics_Wolf_Sheep_Predation_Example.nlogo).

References & Links

• Bybee, G. and L. A. Eng (2012). Airport Security Line Simulation. Available at http://beyondbitsandatomsblog.stanford.edu/spring2012/assignments/assignment-4-creating-netlogo-models/airport-security-line-simulation-netlogo-abm/ [Accessed on April, 10th, 2017].
• Shiflet, A. B., & Shiflet, G. W. (2014). Introduction to Computational Science: Modeling and Simulation for the Sciences. Princeton University Press, Princeton, NJ.
  • The SD SIR model can be found on the accompanying website: https://ics.wofford-ecs.org/dynamics/NetLogo
• Wilensky, U. (1998). NetLogo Life model. http://ccl.northwestern.edu/netlogo/models/Life. Center for Connected Learning and Computer-Based Modeling, Northwestern University, Evanston, IL.
• Wilensky, U. (2005). NetLogo Wolf Sheep Predation (System Dynamics) model. http://ccl.northwestern.edu/netlogo/models/WolfSheepPredation(SystemDynamics). Center for Connected Learning and Computer-Based Modeling, Northwestern University, Evanston, IL.